Перевод с русского языка на английский язык

Translation from Russian into English

                                                                                              Translation from Russian into Spanish

Approved by

Order of the Federal

Environmental, Industrial

and Nuclear Supervision Service

dated 2 March 2018 No. 93

FEDERAL RULES AND REGULATIONS

IN THE FIELD OF ATOMIC ENERGY USE "RULES FOR ARRANGEMENT

AND SAFE OPERATION OF

PRESSURE VESSELS FOR

NUCLEAR FACILITIES"

(NP-044-18)

I. General

Purpose and scope

1. These Federal Rules and Regulations in the field of atomic energy use "Rules for arrangement and safe operation of pressure vessels for nuclear facilities" (hereinafter referred to as the Rules) are developed in accordance with Federal Law No. 170-FZ dated 21 November 1995 "On atomic energy use", Provisions for development and approval of federal rules and regulations in the field of atomic energy use approved by Decree of the Government of the Russian Federation No. 1511 dated 1 December 1997 (Collected Acts of the Russian Federation, 1997, N 49, art. 5600; 2012, N 51, art. 7203).

2. These Rules establish the requirements for design, manufacturing, refurbishment (retrofitting), installation, adjustment, repair, technical diagnostics and operation of pressure vessels and cylinders specially designed for application in the field of atomic energy use, located and operated at the territory of a nuclear facility and referred to safety class 4 (according to classification established in compliance with federal rules and regulations in the field of atomic energy use).

3. These Rules shall be applicable to:

1) pressure vessels containing water with the temperature exceeding 115 °C or any other non-toxic and non-fire-and-explosion-hazardous liquids with the temperature exceeding the boiling temperature at the gauge pressure of 0.07 MPa regardless of hydrostatic pressure;

2) pressure vessels (containing steam, gas, harmful substances referred to hazard classes 1 and 2 with regard to their impact on human organism or fire-and-explosion-hazardous liquids) at the gauge pressure exceeding 0.07 MPa regardless of hydrostatic pressure;

3) vessels for transportation and storage of compressed and liquefied gases with gauge pressure of vapors exceeding 0.07 MPa at the temperature below 50 °C;

4) vessels for transportation and storage of compressed and liquefied gases, liquids and granular materials in which gauge pressure of more than 0.07 MPa is created periodically for their emptying;

5) cylinders intended for transportation and storage of compressed, liquefied and dissolved gases at the gauge pressure exceeding 0.07 MPa.

4. These Rules shall not be applicable to:

1) vessels with the capacity not exceeding 0.025 m³ (regardless of pressure) used for scientific and experimental purposes. The space occupied by the lining, tubes and any other internals shall be excluded from the total volume of the vessel in order to determine its capacity. A group of vessels as well as vessels consisting of individual casings and connected by pipes with the inner diameter of more than 100 mm shall be considered as a single vessel;

2) vessels and cylinders with the capacity of not more than 0.025 m³ with the product of pressure (MPa) and capacity (m³) not exceeding 0.02;

3) plate heat exchangers;

4) steam and water heating devices;

5) pipe furnaces;

6) vessels consisting of pipes with the inner diameter not exceeding 150 mm without headers as well as with headers made of pipes with the inner diameter not exceeding 150 mm;

7) parts of machines that are not self-contained vessels (pump or turbine casings, engine cylinders of steam, hydraulic, air machines and compressors).

5. Assessment of compliance for vessels and cylinders (hereinafter - the vessels) shall be performed in accordance with federal rules and regulations in the field of atomic energy use establishing the rules of compliance assessment for the products subject to the requirements related to safety assurance in the field of atomic energy use.

6. Development of the engineering documentation for vessels and their components (including spare parts thereof), design documentation for installation, repair and refurbishment of vessels (hereinafter - design and engineering documentation), process control documentation for manufacturing and repair of vessels (hereinafter - the PCD) as well as operation documentation shall be carried out in accordance with these Rules and also with any other regulations and regulatory documents of the operating organization (including standardization documents regulating the requirements for design, arrangement, manufacturing, refurbishment (retrofitting), adjustment, installation, repair, technical diagnostics and operation of vessels) (hereinafter - the RD).

7. Any modifications in the design of vessels and their components that may become necessary in the course of manufacturing, refurbishment (retrofitting), installation, adjustment, repair and operation of the vessels shall be approved by the vessel design and engineering documentation developer. In case it is impossible and also for vessels purchased abroad, modifications of the design may be approved by the nuclear facility design organization.

8. Design and engineering documentation and the PCD for vessels manufactured prior to entry of these Rules into effect or being manufactured at the moment of entry of these Rules into effect shall not be subject to any amendment.

9. Terms and definitions given in Appendix No. 1 to these Rules are used in these Rules.

II. Design of vessels

General requirements

10. Design of vessels and their main components shall ensure reliable and safe operation within the specified service life of the vessel (vessel component) and provide for the possibility of technical examination, cleaning, flushing, complete emptying, blowdown, repair, in-service inspection of metal and weld joints.

11. The specified service life shall be established for each vessel and indicated in the certificate.

12. Any devices preventing from exterior and interior inspection of vessels shall be removable.

In case any weld-on components are used the possibility for their removal shall be provided in order to perform exterior and interior inspection with their subsequent re-installation. The procedure for removal and installation of these devices shall be specified by the manufacturing organization in the vessel operation guidelines (manual).

13. In case the vessel design prevents from exterior and interior inspection or hydraulic testing prescribed by the requirements of these Rules the design and engineering documentation developer shall specify the procedure, frequency and scope of control in the operation manual in order to ensure timely detection and elimination of defects. If no such instructions are presented in the operation manual the procedure, frequency and scope of control shall be defined by a specialized organization.

14. Design of the vessel internals shall ensure air removal from the vessel in the course of hydraulic testing and water removal after hydraulic testing.

15. Vessels shall have nozzles for filling and draining liquid, for removal of air in the course of the vessel filling during operation and hydraulic testing.

16. A valve, a cock or any other device enabling to control absence of pressure in the vessel prior to its opening shall be installed on each vessel. In this case the medium shall be discharged to a safe place.

17. Strength calculations for vessels and their components shall be performed in accordance with the strength calculation standards established in the regulatory documents.

Strength calculations for the vessels intended for operation under cyclic loads shall be performed with due regard for these loads. In this case the list of controlled and considered loading cycle types shall be presented in the design and engineering documentation of the vessel with indication of their permissible number within the specified service life.

18. Vessels changing their spatial position in the course of operation shall have devices for prevention of their self-tipping.

19. In order to check weld-on quality for rings used to reinforce the apertures for manholes, hatches and nozzles a threaded inspection hole shall be provided in the ring (if it is welded on the outside) or in the wall (if the ring is welded on the inside of the vessel).

This requirement shall be also applied to any plates or other vessel reinforcement components welded on the outside of the casing.

Non-pressure external components shall have drain holes at their lowest points. Any deviations from this requirement shall be permitted provided that absence of necessity for the above-mentioned holes is substantiated.

20. Grounding and electrical equipment of vessels must comply with the regulations for operation of consumer electrical installations and occupational safety rules for operation of consumer electrical installations.

Manholes, hatches, covers

21. Vessels shall be equipped with the required number of manholes for inspection, cleaning and repair of the vessels and also for installation and dismantling of removable internals.

Vessels with the inner diameter exceeding 800 mm shall have manholes and with the inner diameter of 800 mm and less - hatches.

Vessels consisting of a cylindrical casing and grids with tubes attached to them (heat exchangers) and vessels intended for transportation and storage of cryogenic liquids as well as vessels intended for operation with harmful substances referred to hazard classes 1 and 2 according to classification established in the relevant national standards but not causing corrosion and scale formation may be manufactured without manholes and hatches irrespective of the vessel diameters.

22. The inner diameter of round manholes shall be at least 400 mm. The dimensions of oval manholes in the clear along the smallest and the largest axes shall be at least 325 x 400 mm.

The inner diameter of round hatches or the size of oval hatches along the smallest axis shall be at least 80 mm.

23. Manholes and hatches shall be located in the places accessible for maintenance.

24. Manhole covers shall be removable. Weld-on covers are permitted for vacuum-based isolated vessels.

25. Covers with the weight of more than 20 kg shall be equipped with lift-and-turn or other devices for their opening and closing.

26. Design of hinged reclining devices or inserted bolts, collars as well as clamping devices of manholes, covers and their flanges shall prevent their spontaneous displacement.

27. In case vessels are equipped with any nozzles, flange connectors, detachable bottoms or covers with the inner diameter at least equal to the value specified for manholes in par. 22 of these Rules providing for the possibility to carry out interior inspection it is permitted not to arrange manholes.

Vessel bottoms

28. The following bottoms shall be used in vessels:

1) elliptical;

2) semi-spherical;

3) torispherical;

4) spherical unbeaded;

5) conical edge-raised;

6) conical unbeaded;

7) flat edge-raised;

8) flat unbeaded.

29. Elliptical bottoms shall have the convex section height (as measured along the inner surface) of at least 20% of the bottom inner diameter. This value may be reduced subject to approval of the vessel design organization.

30. Torispherical bottoms shall have:

1) the convex section height (as measured along the inner surface) of at least 20% of the inner diameter;

2) the beading inner radius of at least 0.1 of the bottom inner diameter;

3) the inner curvature radius of the central part not exceeding the bottom inner diameter.

31. Spherical unbeaded bottoms may be used with weld-on flanges, in this case:

1) the inner radius of the bottom sphere shall not exceed the inner diameter of the vessel;

2) weld joint between the flange and the bottom shall be with full penetration.

32. In welded dished bottoms (except for semi-spherical ones) consisting of several sections with weld joint located chord-wise the distance from the weld joint axis to the bottom center shall not exceed 1/5 of the bottom inner diameter.

Circular seams of dished bottoms shall be located at the distance not exceeding 1/3 of the bottom inner diameter from the bottom center.

33. Conical unbeaded bottoms shall have the center angle at the cone point not exceeding 45°.

34. Flat bottoms with an annular groove and cylindrical section (edge) manufactured by mechanical boring shall be made of forged pieces. Edge-raised flat bottoms may be made of sheet metal provided that beading is performed by pressing or rolling of the sheet edge with 90° bend.

35. For edge-raised and transition elements of vessels except for dished bottoms, bellows and extended necks for weld-on of nozzles the distance L from the beaded element curve starting point to the raised edge depending on the edge-raised component wall thickness s shall be at least equal to the value specified in Table 1 of these Rules.

Table 1

Edge-raised vessel component wall thickness selection

Weld joints and their location

36. Full-penetration butt weld joints shall be used for welding of shells and pipes and welding of bottoms to shells.

Angle and T-shaped full-penetration weld joints are permitted for welding of flat bottoms, flat flanges, tube sheets, nozzles, manholes and jackets.

37.  Application of lap joints is permitted for welding of reinforcement rings, support elements, backing boards, plates for platforms, stairs and brackets to the casing.

38. Weld joints shall be accessible for inspection in the course of manufacturing, installation, repair and operation of vessels provided in these Rules and the design and engineering documentation.

39. Longitudinal joints of adjacent shells and seams of vessel bottoms shall be shifted in relation to each other by the value equal to threefold thickness of the most thick-walled component but at least 100 mm between centers of seams.

It is permitted not to shift the above-mentioned joints in relation to each other in vessels intended to operate under the gauge pressure not exceeding 1.6 MPa and the wall temperature not exceeding 400 °C, with the nominal wall thickness of not more than 30 mm, provided that these joints are performed by automatic or slag welding and the seam intersection points are controlled by radiography or ultrasonic analysis within the scope of 100%.

40. When any internal and external devices (support elements, disks, jackets, baffles) are welded to the vessel casing intersection of these weld joints with butt joints of the vessel casing are permitted subject to prior inspection of the overlapped vessel casing joint section by radiographic or ultrasonic control.

41. When supports or any other elements are welded to the vessel casing the distance between the vessel weld joint edge and the element welding joint edge shall be at least equal to the vessel casing wall thickness but not less than 20 mm.

For vessels made of carbon and low-alloyed manganese and silica-manganese steels subjected to heat treatment after welding the distance between the vessel weld joint edge and the element welding joint edge shall be at least 20 mm (regardless of the vessel casing wall thickness).

42. In horizontal vessels local overlapping of circular (cross-sectional) weld joints by saddle supports is permitted at the total length of not more than 0.35  and with a backing board - not more than 0.5 where D is the outer diameter of the vessel. In this case the overlapped sections of weld joints shall be checked by radiographic or ultrasonic control along the entire length. Overlapping of intersection points in circular and longitudinal vessel casing joints with supports is not permitted.

43. Smooth transition from one component to another shall be ensured in butt weld joints of vessel components with different wall thickness by gradual thinning of the more thick-walled component edge. Inclination angle of the transition surfaces shall not exceed 20°.

In case the difference in thickness of the connected components is not more than 30% of the thick-walled component thickness and does not exceed 5 mm it is permitted to use weld seams without prior thinning of the thick-walled component. Shape of seams shall ensure smooth transition from a thick-walled component to a thin-walled one.

In case a cast part is mated to parts made of pipes, rolled products or forged pieces it should be taken into account that the nominal design thickness of the cast part is 25-40% more than the similar design wall thickness of the component made of pipes, rolled products or forged pieces thus transition from the thick-walled component to the thin-walled one shall be arranged in such a way so that wall thickness at the end of the cast part would be at least equal to the design value.

Location of apertures in the vessel walls

44. Apertures for manholes, hatches and nozzles shall be located beyond weld joints. At the same time it is permitted to locate apertures:

1) on longitudinal joints of cylindrical and conical vessel shells if the nominal diameter of apertures does not exceed 150 mm;

2) on circular joints of cylindrical and conical vessel shells without any limitations of aperture diameters;

3) on joints of dished bottoms without any limitations of aperture diameters subject to 100% control of bottom weld joints by radiographic or ultrasonic methods.

45. Apertures in torispherical bottoms may be located only within the central spherical segment. In this case the distance from the bottom center to the outer aperture edge measured along the chord shall not exceed 0.4D (D is the outer diameter of the bottom).

III. Materials and semi-finished products

46. Materials used for manufacturing, repair and refurbishment (retrofitting) of vessels shall comply with the requirements of the design and engineering documentation and provide reliable operation of vessels within the specified service life with due regard for the prescribed operation conditions (design pressure, minimum negative and maximum design temperature), medium composition and nature (including corrosiveness, explosion hazard, toxicity, radioactivity (if any)) as well as the ambient air temperature influence.

47. Quality and properties of the basic, welding and cladding materials used for manufacturing, repair and refurbishment (retrofitting) of vessels and their components shall comply with the requirements of standardization documents establishing the requirements for products, processes and other standardization objects in the field of atomic energy use prescribed in par. 7 of "Provisions for standardization of products (works, services) subject to the requirements related to safety assurance in atomic energy use as well as processes and other standardization objects associated with such products" approved by Decree of the Government of the Russian Federation dated 12 July 2016. No. 669 (Collected legislation of the Russian Federation, 2016, No. 29, Art. 4839).

48. New basic materials may be applied provided that quality and properties of the applied materials would be at least equal to the quality and properties of previously applied materials and also subject to issuance of the report substantiating application of any new material in accordance with Appendix 2 to federal rules and regulations in the field of atomic energy use "Rules for design and safe operation of equipment and pipelines of nuclear power installations" (NP-089-15) approved by Order of the Federal Environmental, Industrial and Nuclear Supervision Service No. 521 dated 17 December 2015. (Order is registered by Ministry of Justice of the Russian Federation on 9 February 2016, registration number No. 41010). The report shall be approved by the main material research organization. In this case the scope of information contained in the report shall be defined depending on particular vessel operation conditions.

Possibility for application of any new material shall be documented in the form of a technical solution agreed with the vessel design and engineering documentation developer and the main material research organization and approved by the operating organization. A copy of such solution shall be attached to the vessel certificate and substantiating materials shall be stored in the operating organization within the entire service life of the vessel.

49. When selecting materials for vessels intended for outdoor installation or installation in non-heated rooms the absolute minimum temperature of external air for this climatic region shall be taken into account in case the pressure vessel wall temperature can become negative under the impact of ambient air.

50. Quality and properties of materials and semi-finished products shall be confirmed by certificates issued by the manufacturers of materials and semi-finished products.

Heat treatment regime for the semi-finished product and results of chemical analysis obtained directly for this semi-finished product or the similar data for its blank shall be specified in the certificate.

In case of absence or incompleteness of the certificate or labeling the vessel manufacturing organization (repair or installation organization) shall perform additional tests in order to define the missing data with recording of their results in the document supplementing or replacing the material supplier's certificate.

51. Control methods and scope for semi-finished products shall comply with the control methods and scope specified in the semi-finished product RD.

52. Additive materials used in manufacturing, repair or refurbishment (retrofitting) of vessels (including fluxes and protective gases) shall comply with the RD requirements for welding materials.

53. Application of new additive materials, fluxes and protective gases shall be permitted by the manufacturing organization management subsequent to confirmation of their processibility in the vessel welding, checks of the entire set of required weld joint properties (including seam metal properties) and positive opinion of the specialized welding organization.

54. Application of electric-welded pressure pipes with longitudinal or spiral seams in vessels shall be permitted subject to the seam control by radiographic and ultrasonic methods along the entire length.

55. Each seamless or electric-welded pipe shall be subjected to hydraulic testing after manufacturing, installation or repair. Hydraulic testing pressure value shall be specified in the design and engineering documentation. It is permitted not to perform hydraulic testing of seamless pipes in case they are subjected to ultrasonic or eddy current control along the entire length.

56. Plated and deposited sheets and forged pieces with cladding shall be subjected to ultrasonic control or control by any other methods ensuring detection of any plating (deposited) layer separation from the basic metal layer as well as discontinuities and spilly metal of forged pieces and spilly metal of sheets. In this case the quality assessment scope shall be established by the standards or technical specifications for plated or deposited sheets and forged pieces. Bimetal sheets with the thickness of more than 25 mm intended for manufacturing, repair and refurbishment (retrofitting) of pressure vessels with the gauge pressure exceeding 4 MPa shall be subjected to complete control by ultrasonic analysis or any other equivalent methods.

57. Carbon and low-alloyed steel sheets with the thickness of more than 60 mm intended for manufacturing, repair and refurbishment (retrofitting) of pressure vessels with the gauge pressure exceeding 10 MPa shall be subjected to sheet-by-sheet control by ultrasonic analysis or any other equivalent flaw detection methods.

58. Forged pieces made of carbon, low-alloyed and alloyed steels intended for operation at the gauge pressure exceeding 6.3 MPa and having any dimension exceeding 200 mm and the thickness of more than 50 mm shall be subjected to piece-by-piece control by ultrasonic analysis or any other equivalent method.

At least 50% of the controlled forged piece volume shall be subjected to flaw detection. In case any defects are detected the entire forged piece shall be subject to control. Control procedures and standards shall comply with the regulatory documents.

59. Nuts and pins (bolts) shall be made of different steel grades; in case they are made of the same steel grade steel hardness shall be different. In this case the nut hardness shall be less than the pin (bolt) hardness.

It is permitted to have pins (bolts) and nuts made from the same steel grade if hardness of nuts is lower than hardness of pins (bolts) by at least 15 HB.

Length of pins (bolts) shall ensure protrusion of the threaded part above a nut (after the nut tightening) by at least two complete turns.

60. Material of pins (bolts) shall be selected with the linear expansion coefficient close to the linear expansion coefficient of the flange material. Difference in the linear expansion coefficients shall not exceed 10%. Application of steels with different linear expansion coefficients (more than 10%) is permitted in cases substantiated by strength calculations.

61. It is permitted to use nuts made of pearlitic steels on pins (bolts) made of austenitic steels if it is substantiated and confirmed by calculations and tests.

62. In case fastening elements are manufactured by cold forming they shall be subject to heat treatment.

63. Cast steel pieces shall be subject to heat treatment. Mechanical properties of cast pieces shall be checked after their heat treatment.

64. Non-metal materials used in manufacturing, installation, repair and refurbishment (retrofitting) of vessels shall be compatible with the working medium with regard to corrosion resistance and insolubility within the operating range of temperatures. Application of non-metal materials is permitted subject to justifying calculations and experimental substantiation.

65. Filler and binder materials applied in manufacturing, repair and refurbishment (retrofitting) of vessels shall have warranted periods of use specified in the certificates of these materials.

66. Cast pieces made of ductile cast iron shall be used in heat-treated state. Cast iron pieces may be used to manufacture vessels referred to safety class 4.

67. Necessity for heat treatment of thread made by knurling shall be specified in the design and engineering documentation for the vessel which includes the fastener under consideration.

IV. Manufacturing, installation, adjustment, repair and refurbishment

(retrofitting) of vessels

General requirements

68. Manufacturing (reworking), installation, technical diagnostics and adjustment of vessels and their components for nuclear facilities shall be performed by specialized organizations having the conditions necessary for proper performance of the works according to the technology developed in compliance with the requirements of these Rules and the design and engineering documentation for the vessel.

Installation, adjustment and technical diagnostics in the course of adjustment and refurbishment of vessels operated at the nuclear facility may be performed by the owner organization or any relevant specialized organization according to its decision.

69. The quality control system (incoming, in-service, acceptance control) established by the administrative documents of the organization performing the works shall be applied in the course of manufacturing, installation, repair and refurbishment (retrofitting) with the use of welding and heat treatment in order to ensure performance of the works in accordance with these Rules and the process control documentation.

The incoming control procedure for non-metal materials used to manufacture load-bearing elements of the vessel structure shall be approved by the main material research organization, the vessel owner organization or any specialized organization performing the above-mentioned works.

Tolerances

70. Deviation of the outer (inner) diameter of shells, cylindrical edge-raised bottom components, spherical bottoms made of sheets and forged pieces shall not exceed 1% of the nominal diameter.

Relative out-of-roundness within 1% in any cross-section is permitted. Relative out-of-roundness value is determined according to the formulas:

in the cross-section with nozzles and manholes:

,

in the cross-section without nozzles and manholes:

,

where:

,  is the maximum and the minimum outer (inner) vessel diameter respectively, mm;

 is the inner diameter of the nozzle or manhole, mm.

Relative out-of-roundness value for vessels with the ratio between the shell wall thickness and the inner diameter of 0.01 and less may be increased to 1.5%.

Relative out-of-roundness of the vessel components operated under eternal pressure shall not exceed 0.5%.

71. Peaking (angularity) f of edges in weld seams shall not exceed  f = 0.1s + 3 mm, but not more than the relevant values specified in Table 2 of these Rules for vessel components (Figure 1).

Figure 1. Peaking (angularity) of edges in weld seams

Table 2

Maximum peaking (angularity) of edges in butt joints, mm

--------------------------------

<*> D - inner diameter, mm.

72. Misalignment of sheet edges b (Figure 2) measured on the median surface in the butt joints determining the vessel strength shall not exceed b=0.1s but shall be not more than 3 mm. Misalignment of edges in circular seams except for the seams performed by slag welding shall not exceed the values specified in Table 3 of these Rules. Misalignment of edges in circular seams performed by slag welding shall not exceed 5 mm.

Figure 2. Misalignment of sheet edges

Table 3

Misalignment of edges in circular seams

--------------------------------

<*> Subject to cladding on the mated surfaces with the gradient of 1:3 for weld joints with the edge misalignment exceeding 5 mm.

73. Tolerances not specified in this section shall comply with the requirements of regulatory documents.

Welding

74. The welding technique having passed validation testing in accordance with the requirements established by the operating organization shall be applied in the course of any reworking at the place of operation, installation, repair, refurbishment (retrofitting) of vessels.

The PCD shall contain instructions on the metal welding technique adopted for manufacturing of vessels and their components, application of additive materials, control types and scope as well as preliminary and concurrent heating and heat treatment.

75. Plants, equipment and devices ensuring implementation of the relevant technique shall be used for welding.

76. Welding operators having licenses for performance of these welding works issued in accordance with the procedure established by the operating organization shall be admitted to perform welding and tacking of vessel components. Welding operators shall perform only the types of welding works they are admitted to in accordance with the licenses.

77. Any welding operator in the organization who commences welding of pressurized items for the first time regardless of the license availability shall not be admitted to works without passing verification by welding and control of a test weld joint. Design of test weld joints as well as quality control methods and scope for these weld joints shall be established by the welding work supervisor.

78. Supervision over the works for assembly and welding of vessels and weld joint quality control shall be assigned to specialists checked for knowledge of these Rules.

79. Weld joints of the pressurized components with the wall thickness exceeding 6 mm shall be subject to labeling (stamping by a stamp with initials) enabling to define the surname of the welding operator who has performed the welding. The labeling system shall be specified in the process control documentation.

In case any weld joint has been performed by several welding operators the stamp of each welding operator participating in its performance shall be applied in accordance with the procedure specified in the PCD.

The labeling technique shall eliminate work hardening, additional heating or unacceptable metal thinning and ensure integrity of the labeling within the entire service life of the vessel.

80. Labeling necessity and technique for weld joints with the wall thickness of 6 mm and less shall be established by the PCD requirements.

81. In case all weld joints of the vessel have been performed by the same welding operator it is permitted not to label each weld joint. In this case the welding operator's stamp shall be applied near the nameplate or at any other open section of the vessel and the labeling place shall be enclosed in a box drawn with indelible paint. The labeling points shall be specified in the equipment certificate (or on the assembly drawings attached to the certificate).

82. Prior to commencement of welding works assembly quality of the connected components as well as the state of mated edges and adjacent surfaces shall be checked. Fitting of edges by the impact method or local heating is not permitted.

83. Application of gas welding for any parts made of austenitic and high-chromium steels of martensitic and martensitic-ferritic classes in the course of manufacturing, installation, repair and refurbishment (retrofitting) of vessels is not permitted.

84. Subsequent to welding, the joint and adjacent areas shall be cleaned from any slag, metal splash and other contaminants.

Inner burr on the pipe joints made by electrical resistance welding shall be removed in order to ensure the prescribed flow area.

Quality of cleaning and the area of additional cleaning for non-destructive control shall be defined in accordance with the process control documentation.

85. All welding works shall be performed indoors at positive temperature of the ambient air.

In the course of manufacturing, repair and refurbishment (retrofitting) of vessels operated outdoors welding works may be performed at negative temperatures of the ambient air subject to compliance with the PCD requirements. In this case welding areas and the welding operator shall be protected against direct impact of wind and precipitation.

Necessity and regime of preliminary and concurrent heating of the welded parts shall be defined by the welding technique and specified in the process control documentation.

In case of sub-zero temperature of the ambient air, heating shall be arranged in the same cases as for positive one but the heating temperature shall be higher by 50°C.

86. Welding materials applied for welding of vessels shall be validated which shall be confirmed by the supporting documents for these materials submitted by the manufacturing organization.

87. Grades, assortment, storage conditions and preparation of the welding materials for use shall comply with the PCD requirements.

88. Welding materials shall be subject to incoming control. In this case the following shall be controlled:

1) each batch of welding electrodes:

for welding and processing properties;

for compliance of the alloying element content in the weld metal arranged with the use of alloyed electrodes (E-09H1М, E-09H1МF types, austenitic) with the standard composition through chemical composition control by positive material identification test or any other spectrum analysis method used for chemical composition control;

2) each batch of flux cored wire - for welding and processing properties;

3) each coil (bundle, bobbin) of alloyed welding wire - for presence of the basic alloying elements by positive material identification test.

89. Preparation of edges and surfaces for welding shall be performed by mechanical processing or by thermal cutting or gouging (oxygen, air arc or plasma arc) with subsequent mechanical processing (with a cutter, miller or abrasive tool).

Depth of mechanical processing after thermal cutting (gouging) shall be defined in accordance with the process control documentation.

90. Edges of parts to be welded and adjacent areas shall be cleaned from any slag, paint, oil and other contaminants in accordance with the RD requirements.

91. Weld-on and removal of auxiliary components (assembly tools, fastener tacks etc.) shall be performed in accordance with the process control documentation. These components shall be welded on by the welding operator admitted to welding of this item.

92. Tack weld of the components assembled for welding shall be arranged with the use of the same welding materials as used (or permitted for use) in welding of this joint. In the course of further welding works tack welds shall be removed or re-welded with a principal weld.

Weld-on and removal of fastener tacks after completion of the main item welding shall be performed through the use of techniques eliminating any possibilities for cracking and hardening in the item metal.

Heat treatment

93. Heat treatment of vessels (vessel components) shall be performed in the cases established by the process control documentation with due regard for recommendations of the manufacturing organization specified in the operation manual.

94. Heat treatment operators having passed special training and the relevant tests and possessing licenses for performance of these works shall be admitted to carry out heat treatment works.

95. Vessels (vessel components) with the walls where any unacceptable residual stress can occur after manufacturing (including in the course of expanding, pressing and welding) as well as vessels requiring heat treatment in order to achieve strength shall be subject to heat treatment.

96. Vessel components made of carbon and also low-alloyed manganese and silica-manganese steels manufactured through the use of welding, pressing or expanding shall be subject to mandatory heat treatment in the following cases:

1) wall thickness of a cylindrical or conical component of the vessel bottom, flange or nozzle at the point of weld joint exceeds 36 mm for carbon steel and 30 mm for low-alloyed manganese and silica-manganese steel;

2) nominal wall thickness of cylindrical or conical vessel (nozzle) components made of sheet steel by expanding (pressing) exceeds the value calculated by the formula:

S = 0.009(D + 1200),

where D is the minimum inner diameter, mm  (these requirements shall not be applied to edge-raised jackets);

3) they are intended for operation in media causing corrosion cracking;

4) bottoms and other components are pressed (expanded) at the pressing (expanding) end temperature of below 700 °C;

5) bottoms of vessels and their components regardless of thickness are manufactured by cold pressing or cold flanging.

97. Bended pipe sections made of carbon and low-alloyed steel with the outer diameter of more than 36 mm shall be heat-treated if the ratio of the mean bend radius to the nominal outer diameter of the pipe is less than 3.5 and the ratio of the nominal pipe wall thickness to its nominal diameter exceeds 0.05.

98. Vessel bottoms manufactured of austenitic steel by cold pressing or flanging shall be subject to heat treatment.

99. Bottoms and parts made of austenitic chromium-nickel steel pressed (expanded) at the temperature of at least 850 °C do not require any heat treatment.

It is permitted not to subject hot-pressed bottoms to heat treatment if they are made of austenitic steel and have the ratio of the inner diameter to wall thickness of more than 28 and are not intended to be operated in any media causing corrosion cracking.

100. The type of heat treatment (including  tempering, annealing, temper hardening or austenite conditioning) and its regime (including heating rate, temperature and time of hold-up, cooling conditions) shall be defined in accordance with the process control documentation.

101. Vessels (vessel components) may be heat-treated in parts with subsequent local heat treatment of the closure seam. Uniform heating and cooling in accordance with the technique approved by the main material research organization shall be ensured in the course of local heat treatment.

In case any requirements for corrosion cracking resistance are applied, the possibility for local heat treatment of the vessel shall be approved by the specialized organization.

Heating temperature at any point of the vessel (component) in the course of heat treatment in a furnace shall not go beyond the maximum and the minimum temperature prescribed by the heat treatment regime. In this case the medium in the furnace shall not have any adverse effect on the heat-treated vessel (component).

102. Properties of the metal of vessels and their components after all heat treatment cycles shall comply with the PCD requirements with due regard for recommendations of the manufacturing organization specified in the operation manual.

103. Heat treatment shall be performed in such a way so that to provide uniform heating of metal for the items, its free thermal expansion and absence of any plastic deformations. Regimes of heating, hold-up and cooling in the course of heat treatment of items shall be recorded automatically.

104. Other methods prescribed in the process control documentation may be applied instead of heat treatment in order to remove residual stress in vessels (vessel components) made of carbon and also low-alloyed manganese and silica-manganese steel and manufactured through the use of welding, pressing or expanding.

Weld joint quality assurance

105. The weld joint quality assurance system ensuring detection of unacceptable defects, high quality and reliable operation of the equipment and its components shall be applied in the course of vessel reworking at the operation site, installation, repair and refurbishment (retrofitting).

The weld joint quality control system shall include:

1) personnel qualification control;

2) control of assembly and welding, thermal and monitoring equipment, devices, instrumentation and tools;

3) quality control for the basic welding (cladding) materials;

4) quality control for welding materials and materials for non-destructive testing;

5) in-process control of the assembly and welding technique;

6) non-destructive control of weld joints;

7) destructive control of weld joints;

8) control of defect elimination.

Control methods shall be selected in accordance with the requirements of these Rules and specified in the process control documentation.

Results of all control types shall be documented.

Weld joint quality control shall be performed in accordance with the procedure specified in the design and engineering documentation and the process control documentation.

106. Specialists having passed special theoretical and practical training and proficiency verification and duly admitted to perform the works in accordance with the procedure established in the regulatory documents shall carry out control of weld joints.

107. The vessel hazard group depending on the design pressure, wall temperature and nature of the medium shall be defined in accordance with Table 4 of these Rules in order to determine the methods and scope of the weld joint quality control.

If the above-mentioned combinations of pressure and temperature parameters are not specified in Table 4 the medium parameter which is less favorable for the vessel operating conditions shall be taken as the basis to define the group.

The wall temperature shall be determined on the basis of thermotechnical calculations or measurement results, and if no such data are available it should be assumed to be equal to the temperature of working medium contacting the vessel wall.

The scope of control shall be established in the design and engineering documentation and shall be at least equal to the scope prescribed in these Rules.

Table 4

Classification of vessels into hazard groups

108. The requirements of design and engineering documentation and process control documentation shall be observed in the course of vessel manufacturing, installation, repair and refurbishment (retrofitting) with regard to control of:

1) conformity of metal of welded parts and welding materials;

2) compliance of quality of edge preparation and pre-welding assembly;

3) compliance with the welding and heat treatment process requirements.

109. The main control methods for metal and weld joints include:

1) visual and dimensional inspection;

2) radiographic control;

3) ultrasonic analysis;

4) atomic emission spectral analysis (positive material identification test);

5) hardness measurement;

6) hydraulic testing;

7) pneumatic testing;

8) magnetic powder control.

Besides any other control methods (acoustic emission, magnetography, capillary control, determination of ferritic phase content in the weld metal) within the scope prescribed in the design and engineering documentation may be applied.

110. Mechanical testing, metallographic studies and testing for inter-crystalline corrosion resistance shall be performed in the course of destructive control within the scope prescribed in the design and engineering documentation.

111. Acceptance control of items, assembly units and weld joints shall be performed after completion of all processing operations associated with heat treatment, metal deforming and work-hardening.

Sequence of control by individual methods shall comply with the requirements of the process control documentation. Visual and measuring control shall precede any other methods of control.

112. Control of weld joints shall be performed in accordance with the procedures developed by the vessel manufacturing organization and approved by the main material research organization.

113. Control methods and scope for weld joints of weld-on parts not intended for operation under internal pressure shall be specified in the design and engineering documentation.

114. Observance of the PCD requirements by the work performers shall be checked in the course of in-process control.

115. Results for each type of control (including in-process one) shall be registered in the reporting documents (log sheets, data collection sheets, protocols, process certificates).

116. Measuring means shall be subject to metrological verification (calibration) and testing equipment shall be subject to validation.

117. Each batch of defectoscopy materials (penetrants, powders, suspensions, radiographic film, chemical reagents) shall be subject to incoming control prior to use.

118. A weld joint shall be deemed serviceable in case no internal and external defects beyond the acceptable limits are detected in the course of control.

119. Information on the weld joint control for the main components of pressure vessels specified in the design and engineering documentation shall be recorded in the vessel certificate.

120. All weld joints of vessels and their components shall be subject to visual and measuring control in the course of manufacturing, installation, repair and refurbishment (retrofitting) in order to detect the following defects:

1) cracks of all types and directions;

2) holes and porosity on the external surface of the joint;

3) undercuts;

4) rolls, arc strikes, unfilled craters;

5) misalignment and joint edge peaking of the welded components beyond the limits specified in these Rules;

6) non-linearity of the connected components;

7) non-compliance of the joint shape and dimensions with the RD requirements.

121. Prior to visual and measuring control the weld joint surface and adjacent sections of basic metal with the width of at least 20 mm on both sides of the joint shall be cleaned from any slag and other contaminants; in case of slag welding this distance shall be at least 100 mm.

122. In case of double-sided access visual and measuring control shall be performed from the exterior and the interior side along the entire length of seams. In case it is impossible to perform visual and measuring control of the weld joint from two sides it shall be controlled in accordance with the procedure specified in the vessel operation manual (guidelines).

123. Ultrasonic and radiographic control of weld joints in the course of manufacturing, installation, repair and refurbishment (retrofitting) of vessels shall be performed in order to detect any internal defects in weld joints (including cracks, lack of penetration, pores, slag inclusions).

124. The control method (ultrasonic control, radiographic control or combination of both methods) shall be selected in order to ensure more complete and accurate detection of defects with due regard for peculiarities of the metal physical properties and also for familiarization with this control method for particular type of weld joints.

125. The scope of ultrasonic or radiographic control for butt, corner, T-shaped and other weld joints of vessels (including the joints between manholes and nozzles and the vessel casing) shall comply with the information specified in Table 5 of these Rules.

The above-mentioned control scope shall be applied to each weld joint. Weld joint mating (intersection) points shall be subject to mandatory ultrasonic or radiographic control.

Ultrasonic or radiographic control of seams for weld-on of internal and external devices to the vessel casing shall be performed in case of any relevant requirements in the design and engineering documentation.

Table 5

Scope of ultrasonic or radiographic control

for weld joints of vessels

126. Weld joints of vessels equipped with quick-detachable covers shall be subject to ultrasonic or radiographic control within the scope of 100%.

127. Points of radiographic or ultrasonic control for vessels shall be defined after completion of welding works subsequent to the results of visual inspection and specified in the control reporting documentation.

128. Marking of weld joints and labeling of sections for non-destructive control shall comply with the PCD requirements.

129. In case of any defects in weld joints subjected to ultrasonic or radiographic control within the scope of less than 100% all similar weld joints of the item performed by the same welding operator shall be subject to control by the same method along the entire joint length.

The term "similar weld joints" means weld joints similar with regard to steel grade of the connected parts, design of the joint, grades and assortment of applied welding materials, welding technique, position and regime, heating and heat treatment regimes, with the ratio between minimum (maximum) thickness values and outer diameters of the welded parts not exceeding 1.65.

The ratio between outer diameters may be disregarded for the parts with the outer diameter exceeding 500 mm and flat parts. The ratio between outer diameters of the basic parts (assembly units) may be disregarded for definition of similar corner and T-shaped joints between parts and basic parts (assembly units).

Identical weld joints may be united into a group of similar joints. The term "identical weld joints" means any joints fully complying with the above-mentioned requirements for welding process and having the same thickness and diameters of welded parts made of different steel grades from the same structural class close in their chemical composition, mechanical and physical properties.

130. In case it is impossible to carry out ultrasonic or radiographic control due to inaccessibility of individual weld joints (particularly weld-on seams of nozzles and pipes with the inner diameter of less than 100 mm) or in case these control methods are inefficient quality control for these weld joints shall be performed through layer-by-layer visual inspection in the course of welding with registration of the control results in the special-purpose log sheet and subsequent control of the weld joint within the scope of 100% by capillary or magnetic powder method or any other methods specified in the design and engineering documentation. Information on the applied control method shall be indicated in the vessel certificate.

131. Ultrasonic and radiographic control of butt weld joints may be replaced by any other non-destructive control methods enabling to detect internal defects of the weld joints subject to approval of the design documentation developer and the main material research organization.

132. Reference weld joints shall be subject to ultrasonic or radiographic control along the entire length.

In case any defects are detected in a reference weld joint all manufacturing weld joints represented by this joint and not subjected to any previous flaw detection shall be subject to ultrasonic or radiographic control along the entire length.

133. Capillary and magnetic powder control of weld joints in the course of manufacturing, installation, repair and refurbishment (retrofitting) of vessels are additional control methods specified in the process control documentation in order to detect any surface or sub-surface defects.

134. Capillary and magnetic powder control shall be performed in accordance with the control procedures specified in the design and engineering documentation.

135. Class and sensitivity level of capillary and magnetic powder control shall be specified in the process control documentation.

136. Chemical composition control (chemical analysis) including positive material identification tests shall be performed in accordance with the requirements of guidelines approved by the manufacturing organization and agreed with the vessel developing organization.

137. Positive material identification tests shall be performed in order to confirm compliance of metal alloying (chemical composition) for parts and weld joints with the PCD requirements.

138. The following items shall be subject to positive material identification tests:

1) all welded parts (structural elements) to be made of alloyed steel in accordance with the drawing. Positive material identification tests shall be performed with the use of blanks or purpose-made samples. The quantity of samples, control points, the number of measurements shall be specified in the PCD for the part manufacturing;

2) welding materials in accordance with par. 88 of these Rules (in compliance with the RD for incoming control aimed to check the quality of welding and cladding materials).

139. Weld joint metal hardness measurement shall be performed in order to check quality of heat treatment for weld joints.

140. Weld metal of weld joints made of alloyed heat-resistant steels of pearlitic and martensitic-ferritic classes shall be subject to hardness measurement through the use of methods and within the scope specified in the process control documentation.

Mechanical tests

141. Reference butt weld joints shall be subject to mechanical testing in the course of manufacturing, installation, repair and refurbishment (retrofitting) of vessels in order to check compliance of their mechanical properties with the requirements of these Rules and technical specifications for the vessel manufacturing.

Mandatory types of mechanical tests:

1) static tension - for all groups of vessels;

2) static bending or flattening - for all groups of vessels;

3) impact bending - for the vessels intended for operation under the gauge pressure exceeding 5 MPa or temperature of more than 450 °C and vessels made of steel prone to produce overabundance of martensite in the course of welding;

4) impact bending - for the vessels of groups 1, 2, 3 intended for operation at the temperature below minus 20 °C.

Impact bending tests of the weld joints shall be performed for vessels and their components with the wall thickness of 12 mm and more at the temperature of 20 °C for group 3 and at the operating temperature for group 4.

142. The following samples shall be cut out of each reference butt weld joint:

1) two samples for static tension testing;

2) two samples for static bending or flattening testing;

3) three samples for impact bending testing.

143. Static bending testing for reference butt joints of tubular vessel components with the nominal pipe size of less than 100 mm and wall thickness of less than 12 mm may be replaced by flattening testing.

144. Mechanical tests of weld joints shall be performed in accordance with the requirements of the design and engineering documentation and the process control documentation.

145. Control of mechanical properties, testing for inter-crystalline corrosion resistance and metallographic studies of weld joints shall be performed with the use of samples made from reference weld joints.

Reference weld joints shall reproduce one of the vessel butt weld joints determining its strength (longitudinal seams of shells, chordal and meridional seams of dished bottoms) as well as circular seams of vessels without any longitudinal seams.

Reference weld joint shall be identical to the controlled manufacturing weld joints (with regard to steel grades, sheet thickness or pipe size, edge preparation form, welding technique, welding materials, position of the joint, heating regimes and temperature, heat treatment) and performed by the same welding operator and with the same welding equipment at the same time with the controlled manufacturing weld joint. Reference weld joints for circular seams of multi-layer vessels shall be established by the design and engineering documentation.

146. When welding reference joints (plates) intended to check mechanical properties and to perform tests for inter-crystalline corrosion resistance and metallographic studies the plates shall be tack-welded to the welded components in such a way so that the seam of reference plates would serve as extension of the welded item seam.

Welding of reference plates intended to check the joints of vessel components where tack welding of plates is impossible may be performed separately but with observance of all welding conditions for the controlled butt joints specified in par. 74-92 of these Rules.

147. In order to control quality of weld joints in tubular components with butt joints reference butt joints shall be manufactured concurrently with welding of the latter in the same production conditions so that to test mechanical properties of the joints.  The number of reference butt joints shall be 1% of the total number of similar butt joints welded by each welding operator but at least one butt joint for each welding operator.

148. Welding of reference joints shall in all cases be performed by welding operators who have performed controlled weld joints on the vessels.

149. The sizes of reference joints shall be sufficient to cut the required number of samples for all prescribed types of mechanical tests, tests for inter-crystalline corrosion resistance and metallographic studies as well as for repeated testing.

150. Ultimate tensile strength of the weld metal at the temperature of 20 °C shall comply with the values specified in the regulatory documents for basic metal.

151. Results of static bending tests for steel joints shall be at least equal to the minimum permissible bending angles specified in Table 6 of these Rules.

Table 6

Minimum permissible bending angles for steel joints

152. Impact bending tests for weld joints shall be performed with the use of samples with a notch along the seam axis on the side of its opening unless the notch point is specially indicated in the design and engineering documentation or the process control documentation.

Impact viscosity of steel weld joints shall be at least equal to the values specified in Table 7 of these Rules.

Table 7

Minimum impact viscosity of steel

weld joints

Impact viscosity tests shall be performed with the use of KCU or KCV samples in accordance with the requirements of the manufacturing standard or design and engineering documentation.

153. In the course of flattening tests for pipe weld joints the testing parameters shall be at least equal to the relevant minimum permissible parameters established in the regulatory documents for the pipes of the same schedule made of the same material.

In the course of flattening tests for samples made of pipes with a longitudinal weld seam the latter shall be located within the plane perpendicular to the load direction.

154. Mechanical properties of weld joints shall be determined as the arithmetic mean value of testing results for individual samples.

The general testing results shall be deemed unsatisfactory in case at least one of the samples has demonstrated the result different from the established minimum permissible values by more than 10% downwards in the course of tension, static bending or flattening tests.

Results of impact bending tests shall be deemed unsatisfactory in case at least one sample has demonstrated the result below the value specified in Table 7 of these Rules.

Reduction of KCU impact viscosity to 25 J/cm² in one sample is permitted if the testing temperature is below minus 40 °C.

155. In case unsatisfactory results are obtained for any type of mechanical tests this type of tests shall be repeated on the double number of samples cut out of the same reference butt joint. In case it is impossible to cut samples out of the above-mentioned butt joints repeated mechanical tests shall be carried out on the manufacturing butt joints performed by the same welding operator and cut out of the controlled item.

In case any defects of metallurgical nature are detected at the fracture of the sample which has shown unsatisfactory results repeated tests may be performed on the single number of samples.

In case parameters not complying with the established standards are obtained for at least one of the samples in the course of repeated testing the weld joint shall be deemed faulty.

156. Necessity, scope and procedure for mechanical testing of weld joints for cast and forged components, pipes with cast elements, components made of different steel classes as well as other single weld joints shall be determined in accordance with the design and engineering documentation and the process control documentation.

Reference samples shall be provided for vessels made of non-metal and composite materials. Their design, manufacturing technology and types of testing shall be defined in the design and engineering documentation for the vessel.

Metallographic tests

157. Reference butt weld joints determining strength of the following vessels and their components shall be subject to metallographic studies in the course of manufacturing, installation, repair and refurbishment (retrofitting) of vessels:

1) intended for operation under the gauge pressure exceeding 5 MPa or at the temperature of more than 450 °C as well as at the temperature below minus 40 °C (regardless of the pressure);

2) manufactured of alloyed steel prone to produce overabundance of martensite in the course of welding; double-layer steel; steel prone to hot cracking (established by the developing organization).

It is permitted not to perform metallographic studies for vessels and their components with the thickness of up to 20 mm manufactured of austenitic steels.

158. Samples (thin sections) for weld joints shall be cut across the seam and manufactured in accordance with the process control documentation.

Samples for metallographic studies of weld joints shall include all sections of the seam, both heat-affected zones and the adjacent basic metal sections as well as the backing ring if it has been used in the course of welding and is not to be removed. Samples for metallographic studies of weld joints for the components with the wall thickness of 25 mm and more may include only a part of the joint cross-section. In this case the distance from the fusion line to the sample edges shall be at least 12 mm, and the controlled section area shall be 25x25 mm.

159. Weld joint quality in the course of metallographic studies shall comply with the requirements of par. 120 and 182 of these Rules.

160. In case unsatisfactory results are obtained in the course of metallographic studies repeated testing of two samples cut out of the same reference joint is permitted.

In case unsatisfactory results are obtained in the course of repeated metallographic studies the seams shall be deemed unsatisfactory.

161. In case any internal defects that had to be detected in the course of non-destructive control are revealed by metallographic studies in the reference weld joint checked by ultrasonic or radiographic method and deemed to be acceptable all manufacturing weld joints controlled by the NDT specialist who has performed this control shall be subject to 100% inspection by the same flaw detection method. In this case another NDT specialist shall perform the new quality inspection for all manufacturing butt joints.

162. Necessity, scope and procedure for metallographic studies of weld joints for cast and forged components, pipes with cast elements, components made of different steel classes as well as other single weld joints shall be determined in the design and engineering documentation.

Inter-crystalline corrosion resistance tests

163. Inter-crystalline corrosion resistance tests of weld joints in the course of manufacturing, installation, repair and refurbishment (retrofitting) of vessels shall be performed for vessels and their components made of austenitic, ferritic, austenitic-ferritic steel classes and double-layer steels with a corrosion-proof layer made of austenitic and ferritic steels (if any relevant requirement is specified in the design and engineering documentation).

164. Shape, dimensions, number of samples, testing methods and criteria to assess susceptibility of samples to inter-crystalline corrosion shall comply with the requirements of the design and engineering documentation and the process control documentation.

Hydraulic (pneumatic) testing

165. All vessels shall be subject to hydraulic testing after their manufacturing, installation, repair and refurbishment (retrofitting) with the use of welding as well as in the course of their technical examination with the frequency established by these Rules.

166. Vessels with protective coating or insulation shall be subject to hydraulic testing prior to application of coating or insulation.

Vessels with external covers shall be subject to hydraulic testing prior to the cover installation.

Enameled vessels may be subjected to hydraulic testing under operating pressure after enameling.

167. Hydraulic testing of vessels except for cast ones shall be performed under the testing pressure determined in accordance with the formula:

,

where:

P is the working pressure of the vessel (the system including the vessel), MPa;

,  - permissible stresses for the material of the vessel or its components at 20 °C and at the design temperature respectively, MPa.

The ratio  shall be assumed for the material of the vessel components (shells, bottoms, flanges, fasteners, nozzles) for which it is the least.

168. Hydraulic testing of vessels and parts made of cast pieces shall be performed under the testing pressure determined in accordance with the formula:

.

Testing of cast pieces may be performed subsequent to assembly and welding in an assembled unit or the finished vessel under the testing pressure adopted for vessels subject to 100% non-destructive control of cast pieces.

Hydraulic testing of vessels and parts made of non-metal materials with the impact viscosity of more than 20 J/cm² shall be performed under the testing pressure determined in accordance with the formula:

.

Hydraulic testing of vessels and parts made of non-metal materials with the impact viscosity of 20 J/cm² and less shall be performed under the testing pressure determined in accordance with the formula:

.

169. Hydraulic testing of cryogenic vessels with vacuum in the insulating space shall be performed under the testing pressure determined in accordance with the formulas:

P_t = 1.25P - 0.1 MPa

or

P_t = 1.25P - 1 kgf/cm².

Hydraulic testing of steel-plastic vessels shall be performed under the testing pressure determined in accordance with the formula:

P_t = [1.25 K_m + α(1 - K_m)] P[σ]₂₀ / [σ]_t,

where:

K_m is the ratio of the metalwork weight to the total weight of the vessel;

 = 1.3 - for non-metal materials with the impact viscosity of more than 20 J/cm²;

 = 1.6 - for non-metal materials with the impact viscosity of 20 J/cm² and less.

170. In the course of hydraulic testing for vertically erected vessels pressure shall be controlled through the use of two pressure gages installed on the top cover and bottom of the vessel. If it is impossible, the hydrostatic head pressure applied in the course of hydraulic testing shall be taken into account through calculations.

In this case the testing pressure shall be determined with due regard for hydrostatic pressure applied to the vessel in the course of its operation.

171. In the course of the vessel filling with water (liquid) for the purpose of hydraulic testing air shall be completely removed.

172. In combined vessels with two and more working spaces designed for different pressures each space shall be subject to hydraulic testing under the test pressure depending on the operating pressure in this space.

The testing procedure shall be described in the design and engineering documentation and specified in the vessel operation manual (guideline).

173. Water with the temperature of not less than 5 °C and not more than 40 °C shall be used for hydraulic testing of vessels unless any particular temperature value permissible in order to prevent brittle failure is specified in the design and engineering documentation.

Temperature difference between the vessel wall and the external air in the course of testing shall not cause condensation of moisture on the vessel wall surfaces.

Any other liquid without adverse impact on the vessel may be used instead of water upon agreement with the developing organization.

174. In the course of the equipment filling with water air shall be completely removed. Pressure in the vessel under testing shall be increased gradually and uniformly. The total pressure increase time (up to the testing value) shall be specified: for the vessel testing in the manufacturing organization - in the process control documentation, for the vessel testing in the course of operation - in the operation manual (guideline).

It is not permitted to use compressed air or any other gas to raise pressure in the vessels filled with water.

175. Water pressure in the course of hydraulic testing shall be controlled with at least two pressure gages. Both pressure gages shall be of the same type, measuring limit, grade of accuracy (at least 1.5) and scale interval.

176. The time of the vessel exposure to the testing pressure in the course of manufacturing, installation, repair, refurbishment (retrofitting) and technical examination shall be specified in the operation manual (guideline) and shall be at least 10 minutes.

In case no instructions are presented in the operation manual (guideline) the time of exposure to the testing pressure for vessels of element-by-element package supply reworked in the course of installation at the operation site shall be at least equal to the values specified in Table 8 of these Rules.

Table 8

Time of exposure to the testing pressure for vessels

reworked in the course of installation at the operation site

177. Subsequent to hold-up under the testing pressure the pressure shall be reduced to the value substantiated in the strength calculations but at least equal to the working pressure and visual inspection of the exterior surface of the equipment and all its detachable and non-detachable joints shall be performed.

Tapping of the vessel casing walls, weld and detachable joints of the vessel in the course of testing is not permitted.

178. The vessel shall be deemed to have passed hydraulic testing if none of the following defects are detected:

1) leaks, cracks, weeps, seepage in weld joints and on the basic metal;

2) leaks in detachable joints;

3) any visible residual deformations;

4) gauge pressure drop.

179. The vessel and its components with any defects revealed in the course of hydraulic testing shall be subject to repeated hydraulic testing under the testing pressure subsequent to elimination of these defects.

180. Testing results and the testing pressure values in the course of testing shall be recorded in the report (in case the tests are performed after manufacturing, repair or refurbishment (retrofitting)) and indicated in the vessel certificate according to the procedure established by the operating organization.

181. In case hydraulic testing is impossible or undesirable according to the process conditions hydraulic testing may be replaced with pneumatic testing (with compressed air or inert gas) subject to control of this testing by acoustic emission or any other method approved by the operating organization and the developing organization.

The testing pressure value shall be equal to the hydraulic testing pressure value with due regard for hydrostatic pressure of the medium under operating conditions. The time of the vessel exposure to the testing pressure shall be defined by the developing organization but shall be at least 5 minutes.

Then the pressure in the vessel under testing shall be reduced to the design value and inspection of the vessel shall be performed with checking of its seams and detachable joints with soap solution or by any other method specified in the regulatory documents.

Weld joint quality assessment

182. The following defects are not permitted in weld joints of vessels and their components:

1) cracks of all types and directions located in the weld metal, along the fusion line and in the heat-affected area of the basic metal including micro-cracks detected in the course of the reference sample micro-analysis;

2) lack of penetration (fusion) in the weld seams located in the weld root or in the weld joint cross-section (between individual weld beads and layers and between the basic metal and the weld metal);

3) undercuts of the basic metal, pores, slag and other inclusions with the dimensions exceeding the permissible limits specified in the regulatory documents;

4) rolls (collars) and ripples;

5) unfilled craters and arc strikes;

6) holes and porosity on the external surface of the joint;

7) misalignment and joint edge peaking of the welded components beyond the limits specified in these Rules.

8) any deviations of physical dimensions and mutual alignment of the welded components;

9) non-compliance of the seam shape and dimensions with the requirements of the process control documentation;

10) defects on the surface of basic metal and weld joints (dents, lamination, air pockets).

183. Quality assessment for weld joints of vessels and their components shall be performed in accordance with the requirements of the process control documentation and federal rules and regulations in the field of atomic energy use establishing the rules of control of basic metal, weld joints and deposited surfaces during operation of equipment, pipelines and other components of nuclear power plants.

Elimination of defects in weld joints

184. Any defects detected in the course of manufacturing, installation and operation of the vessel (including in the course of repair and testing) shall be eliminated with subsequent control of the repaired areas. Defect elimination methods and quality shall ensure the required reliability and safety of the vessel operation.

185. Defect elimination techniques and the control procedure shall be specified in the process control documentation.

Defects shall be eliminated mechanically with arrangement of smooth transition at the weld defect elimination sites. Maximum size and shape of gouges to be welded shall be established in the design and engineering documentation.

Thermal cutting (gouging) techniques may be used for removal of internal defects with subsequent mechanical processing of the weld defect elimination surface. The gouge shape shall ensure the possibility of its weld-up.

Completeness of defect elimination shall be checked visually and by non-destructive control methods (capillary or magnetic powder control or etching).

186. Elimination of defects without any weld-up of the defect elimination sites is permitted subject to maintenance of the minimum permissible wall thickness at the maximum gouging depth point in accordance with the design and engineering documentation.

187. In case any defects are revealed during control of the repaired section repeated elimination of defects may be performed in accordance with the same procedure as the first one.

Elimination of defects at the same section of a weld joint may be performed not more than three times.

Joints cut along the weld seam with removal of weld metal from the heat-affected zone determined in accordance with the design and engineering documentation shall not be considered as repeatedly repaired.

Documentation and labeling

188. Each vessel and cylinder shall be supplied by the manufacturing organization with the relevant certificate. The requirements for contents of the vessel and cylinder certificate are given in Appendix 2 to these Rules.

The operation manual (guideline) and strength calculations (with due regard for cyclic and vibration loads) shall be attached to the vessel and cylinder certificate.

189. Vessel components (casings, shells, bottoms, covers, tube sheets, casing flanges, integrated assembly units) intended for manufacturing, repair or refurbishment (retrofitting) shall be supplied by the manufacturing organization with the manufacturing quality certificate containing data within the scope established in accordance with the requirements of the relevant certificate sections.

190. A plate arranged in accordance with the design and engineering documentation shall be attached to each vessel. It is permitted not to attach the plate to vessels with the outer diameter of less than 325 mm. In this case all necessary data shall be inscribed on the vessel casing by the electrographic method except for the vessels made of austenitic steels (for these vessels data may be inscribed by mechanical engraving).

In case of any repair or refurbishment of the vessel with modification of its design or technical characteristics the relevant changes shall be introduced to the vessel certificate and nameplate.

191. The nameplate shall include the following:

1) trademark or name of the manufacturer;

2) vessel name or designation;

3) serial number of the vessel according to the manufacturer's numeration system;

4) year of manufacture;

5) operating pressure, MPa;

6) design pressure, MPa;

7) testing pressure, MPa;

8) maximum permissible and (or) minimum operating temperature of the wall, °C;

9) weight of the vessel, kg.

In case of the vessels with independent cavities having different design pressure and wall temperature these data shall be indicated for each cavity.

V. Valves, instrumentation and

safety devices of vessels

General

192. Depending on the purpose, vessels shall be equipped with the following in order to control their functioning and ensure safe operation conditions:

1) shutoff or shutoff and control valves;

2) pressure monitoring means;

3) temperature measuring devices;

4) safety devices;

5) liquid level indicators (in case the working medium is liquid with media interface).

193. Vessels equipped with quick-detachable covers shall have safety devices preventing potential pressure build-up in the vessel with incomplete closure of the cover or possibility for the cover opening when the vessel in under pressure. Such vessels shall also have a lock with a labeled key.

194. Valves with the inner diameter of connecting branches exceeding 150 mm and all safety valves shall be supplied together with certificates. A certificate for a batch of items may be issued for other valves. All applied materials as well as heat treatment regimes and results of non-destructive control (if any is prescribed in the design and engineering documentation) shall be specified in the certificate. The above-mentioned data shall refer to the main parts of the valve (casing, cover, stem, gate and fasteners).

Shutoff and shutoff and control valves of vessels

195. Shutoff and shutoff and control valves shall be installed on the nozzles (branches) directly connected to the vessels or on the pipelines supplying and discharging the working medium from the vessel. In case several vessels are connected in series the necessity for installation of such valves between them shall be agreed with the developing organization.

196. The valves shall have the following labeling:

1) name or trademark of the manufacturer;

2) nominal size;

3) nominal pressure (working pressure and permissible temperature may be indicated);

4) medium flow direction;

5) casing material grade.

197. The number, type and installation places of the applied valves shall comply with the vessel design documentation with due regard for particular operating conditions.

Valves intended for operation in explosion-hazardous areas shall be explosion-proof and shall have the protection degree corresponding to the explosion-hazardous area class and type of explosion protection corresponding to the categories and groups of explosion-hazardous mixtures.

198. Direction of rotation for the valve opening or closing shall be indicated on the shutoff valve handwheel.

The handwheels of shutoff valves on thermomechanical equipment shall be painted red.

199. Vessels for explosion-hazardous and fire-hazardous substances, substances of hazard classes 1 and 2 with regard to their impact on the human organism as well as vaporizers with flame or gas heating shall have a check valve on the supply line from the pump or compressor closed automatically by pressure from the vessel. The check valve shall be installed between the pump (compressor) and shutoff valves of the vessel.

200. Valves with the nominal size exceeding 20 mm manufactured of alloyed steel or non-ferrous metals shall have certificates in the established format specifying the manufacturing organization, factory number of the valve, technical characteristics of the valve (nominal size, operating temperature, working pressure), information on chemical composition, mechanical properties, heat treatment regimes and results of the manufacturing quality control by non-destructive methods.

Valves with labeling but without certificates may be applied subsequent to revision of the valves, testing and checks of the material grade. In this case the valve owner shall issue the certificate.

201. All valves shall be subject to revision in accordance with the procedure established by the operating organization prior to installation on pressure vessels.

Gauge pressure monitoring means

202. Each vessel and individual cavities with different pressure shall be equipped with pressure monitoring devices: direct-action devices with in-situ indication (pressure gages, sensors) or secondary hardware for remote transmission, processing and presentation of pressure data.

203. Layout of the pressure monitoring devices shall provide for the possibility to check their operability, to perform maintenance, repair and replacement.

Pressure monitoring means shall be equipped with the devices protecting them against direct impact of harmful substances referred to hazard classes 1 and 2 with regard to their effect on the human organism as well as with the devices  aimed to enable blowdown and drainage of pulse lines.

Pressure monitoring means and pulse lines connecting them to the vessel shall be protected against overheating and freezing.

Measurement ranges of the pressure monitoring means shall provide control of the medium parameters in all modes of the vessel operation and have the necessary margin to control their maximum deviations under emergency conditions.

In case the pressure of the measured medium exceeds 2.2 MPa at least two shutoff valves shall be installed upstream of the pressure monitoring device.

204. In case pressure gages are used as pressure monitoring means they shall be installed in the places accessible for their maintenance and visual reading of their indications.

The nominal casing diameter of the pressure gages installed at the height of up to 2 m from their observation platforms shall be at least 100 mm, at the height of 2 to 3 m - at least 160 mm and at the height of 3 to 5 m - at least 250 mm.

In case any pressure gage is located at the height exceeding 5 m a maintenance platform shall be installed in such a way so that the pressure gage readings could be seen by the operating personnel or a duplicate pressure gage shall be installed at the height ensuring clear visibility of its indications.

A three-way valve or its substitute device enabling periodical testing of the pressure gage through the use of a reference pressure gage shall be installed  between the pressure gage and the vessel.

A separate nozzle with a shutoff device for connection of the second pressure gage may be installed instead of a three-way valve on vessels operated under the gauge pressure exceeding 2.5 MPa or at the medium temperature exceeding 250 °C and also with explosion-hazardous medium or harmful substances referred to hazard classes 1 and 2 with regard to their impact on the human organism.

The necessity to install a three-way valve on mobile vessels shall be determined by the developing organization.

Pressure gages shall have accuracy grade of at least: 2.5 - in case of the vessel working pressure of up to 2.5 MPa; 1.5 - in case of the vessel working pressure of 2.5 MPa to 14 MPa; 1.0 - in case of the vessel working pressure exceeding 14 MPa.

The pressure gage shall be selected with such measurement range so that the working pressure measurement limit is in the second third part of the range (scale).

A red line indicating the vessel operating pressure must be applied to the pressure gage scale. Instead of the red line a plate painted with red and tightly fitted on the pressure gage glass (or self-adhesive film covering the pressure gage casing in order to prevent the glass displacement) may be attached to the pressure gage casing.

205. Verification (calibration) of the pressure monitoring devices with their sealing or stamping shall be performed at least once per 12 months unless any other time limits are specified in the pressure gage documentation.

Besides additional verification of the operating pressure monitoring devices through the use of reference pressure gages shall be performed at least once per 6 months with registration of the results in the verification log. If no reference pressure gage is available additional verification may be performed through the use of a calibrated operating pressure monitoring device with the same measurement range and accuracy grade as the device being verified.

The procedure and time limits for operability checks, types of the pressure monitoring device malfunctions in the course of the vessel operation shall be defined by the operating organization.

Verification of the pressure monitoring device through the use of the reference pressure gage may be replaced with its calibration once per 6 months.

206. Any pressure monitoring device shall not be permitted for use in the following cases:

1) there is no seal or stamp with a record about calibration;

2) calibration time limit is exceeded;

3) the hand will not return to the zero scale mark when the device is turned off by more than half of the permissible error for this instrument;

4) glass is broken or there are other damages that may affect the correctness of the pressure gage readings.

Temperature measurement devices

207. Vessels operating with variable wall temperature shall be equipped with instruments for control of the heating rate and uniformity along the vessel length and height (thermometers, thermal couples, pyrometers, thermal points and infrared imagers) and also benchmarks for monitoring of thermal displacements.

The necessity to equip the vessels with the above-mentioned instruments and benchmarks as well as the permissible vessel heating and cooling rate shall be defined by the developing organization and specified in the design and engineering documentation and the vessel operation manual (guideline).

Overpressure safety devices

208. Each vessel (cavity of a combined vessel) shall be equipped with safety devices aimed to protect against pressure increase above the permissible value.

209. The following may be used as safety devices:

1) spring safety valves;

2) pilot-operated relief valves (hereinafter - PORV) consisting of the main safety valve and the direct-action pulse-operated control valve;

3) burst-disk safety devices;

4) any other devices approved by the operating organization and the developing organization.

210. Design of a spring valve shall eliminate the possibility of the spring over-tensioning above the prescribed value and the spring shall be protected against unacceptable heating (cooling) and direct impact of the working medium in case it has any adverse effect on the spring material.

211. Design of a spring valve shall provide for the device aimed to check operability of the valve in its working condition by its forced opening in the course of operation.

Safety valves without any forced opening devices may be installed in case these devices are undesirable due to the medium properties (explosion-hazardous, flammable, harmful and referred to hazard classes 1 and 2 with regard to impact on the human organism) or due to the process conditions. In this case the valve actuation verification shall be performed through the use of stands.

212. In case the vessel operating pressure is equal to the supply source pressure or exceeds it and the possibility of pressure increase in the vessel due to a chemical reaction or heating is eliminated installation of a safety valve and a pressure gage is not necessary.

213. The vessel designed for the pressure below the supply source pressure shall have an automatic pressure reducing device with a pressure gage and a safety device installed on its supply pipeline from the lower pressure side downstream of the pressure reducing device.

In case any bypass line is installed it shall be also equipped with a pressure reducing device.

214. For a group of vessels operating under the same pressure it is permitted to install one pressure reducing device with a pressure gage and a safety valve on the common supply pipeline upstream of the first branch to one of the vessels.

In this case installation of safety devices on the vessels it is not mandatory provided that the possibility of pressure increase in them is excluded.

215. If an automatic pressure reducing device cannot function reliably due to physical properties of the working medium a flow controller may be installed. In this case overpressure protection shall be provided.

216. The number of safety valves, their sizes and throughput capacity shall be selected in such a way so that to prevent any overpressure in the vessel exceeding the design value by more than 0.05 MPa for the vessels with the pressure of up to 0.3 MPa, by 15% - for the vessels with the pressure of 0.3 to 6.0 MPa and by 10% - for the vessels with the pressure of more than 6.0 MPa.

Overpressure in the vessel by not more than 25% of the working value is permitted with safety valves in operation provided that such overpressure is prescribed in the design and engineering documentation and specified in the vessel certificate.

217. A safety valve shall be supplied together with a certificate and an operation manual (guideline).

The valve flow coefficient for compressible and incompressible media as well as the area it refers to shall be specified in the certificate apart from other information.

218. Safety devices shall be installed on branches or pipelines connected directly to the vessel.

Connecting pipelines of safety devices (supply, discharge and drain) shall be protected against freezing of the working medium in them.

When several safety devices are installed on the same branch (pipeline) the cross-section area of the branch (pipeline) shall be at least 1.25 of the total cross-section area of the valves installed on it.

Flow resistance shall be also taken into account in determination of cross-section for the connecting pipelines with the length exceeding 1 000 mm.

Extraction of the working medium from the branches (and at the sections of connecting pipelines from the vessel to the valves) where safety devices are installed is not permitted.

219. Safety devices shall be located at the places accessible for their maintenance.

220. Installation of shutoff valves between the vessel and the safety device is not permitted.

221. Valves may be installed upstream (downstream) of a safety device provided that two safety devices are installed and interlocking is available to eliminate the possibility of their simultaneous disabling. In this case each of them shall have the throughput capacity specified in par. 216 of these Rules.

If a group of safety devices and valves upstream (downstream) of them are installed, the interlock shall be designed in such a way so that in case of any disabling of valves provided in the design and engineering documentation the safety devices remaining operable would have the total throughput capacity specified in par. 216 of these Rules.

222. Discharge pipelines of safety devices and PORV pulse lines at the places with potential accumulation of condensate shall be equipped with drainage systems for condensate removal.

Installation of shutoff devices or any other valves on the discharge pipelines of safety devices is not permitted. The medium coming out of the safety devices and drains shall be discharged to a safe place.

Discharged toxic, explosive and flammable process media should be supplied to closed systems for further disposal or to the controlled incineration system.

It is not permitted to combine discharges containing substances that can produce explosive mixtures or unstable compounds in case of their mixing.

223. Membrane-type safety devices shall be installed:

1) upstream of safety valves in cases when the safety valves cannot function reliably due to harmful impact of the working medium (corrosion, erosion, polymerization, crystallization, sticking, freezing) or in case of potential leakages of explosive, fire-hazardous, toxic and environment-unfriendly substances through a closed valve; in this case the device enabling to control good state of the membrane shall be provided;

2) in parallel with the safety valves to increase the throughput capacity of the pressure-relief systems;

3) downstream of safety valves to prevent harmful impact of the working media from the relief system and to eliminate the effect of the back pressure fluctuations in the system on actuation accuracy of the safety valves.

Necessity and places for installation of membrane-type safety devices as well as their design shall be determined by the developing organization.

224. Safety membranes shall be labeled, in this case the labeling shall not affect actuation accuracy of the membranes.

Contents of the labeling:

1) name (designation) or trademark of the manufacturing organization;

2) membrane batch number;

3) membrane type;

4) nominal diameter;

5) working diameter;

6) material;

7) minimum and maximum actuation pressure for the membranes in the batch at the specified temperature and at the temperature of 20 °C.

Labeling shall be applied on the circular edge section of membranes, or membranes shall have marking tags (labels) attached to them.

225. A certificate issued by the manufacturing organization shall be provided for each batch of membranes.

226. Safety membranes shall be installed only in the fastener assemblies provided for them.

227. Connecting pipelines to the safety membranes shall be protected against freezing of the working medium in them.

228. Membrane-type safety devices shall be located at the places open and accessible for inspection, installation and dismantling; connecting pipelines shall be protected against freezing of the working medium in them, and the devices shall be installed on the branches or pipelines connected directly to the vessel.

229. In case the membrane-type safety device is installed in series with the safety valve (upstream or downstream of the valve) the cavity between the membrane and the valve shall be connected to the alarm pressure gage with a branch pipe (in order to monitor good state of the membranes).

230. A switching device may be installed upstream of the membrane-type safety devices subject to double quantity of membrane-type devices with assurance of overpressure protection for the vessel in any position of the switching device.

231. The procedure, time limits and results of operability verification for the safety devices depending on the process conditions shall be specified in the operation manual (guideline) for safety devices approved by the operating organization in accordance with the established procedure.

Verification of functional capabilities (operability) and setting of the safety devices shall be performed after installation, repair, any repair of the safety devices or the control system affecting the settings but at least once per 12 months (for nuclear power installations - at least once per each fuel campaign).

Works shall be performed in accordance with the work program, and their results shall be recorded in the report approved by the operating organization.

Verification results for safety devices, information on their adjustment shall be recorded in the shift log sheet of the operating personnel. Information on their adjustment shall be registered in the reports issued by the persons performing these operations.

Subsequent to adjustment of safety valves the adjustment module shall be sealed.

Liquid level indicators

232. In case of necessity to monitor liquid level in the vessels with the media interface level indicators shall be used.

233. Liquid level indicators shall be installed in accordance with the design and engineering documentation and guidelines of the manufacturing organization, in this case proper visibility of the level shall be ensured.

234. At least two direct-action level indicators shall be installed on vessels heated with flame or hot gases where the liquid level decrease below the permissible value is possible.

235. Design, number and places for installation of level indicators shall be determined by the developing organization.

236. Permissible upper and lower levels shall be marked on each liquid level indicator in accordance with the requirements established in the design and engineering documentation.

237. Permissible upper and lower liquid levels in the vessel shall be determined by the developing organization. Height of a transparent liquid level indicator shall be at least 25 mm below the lower permissible liquid level and above the upper one respectively.

In case it is necessary to install several indicators they shall be located along the height in such a way so that to ensure continuous liquid level indication.

238. Level indicators shall be equipped with valves (cocks and vents) for their isolation from the vessel and blowdown with the working medium discharge to a safe place.

239. If glass or mica is used as a transparent element in the level indicators  a protective device shall be provided in order to protect the personnel against injuries in case of their breakage.

VI. Installation and technical examination of vessels

Installation of vessels

240. Vessels shall be installed at open sites in the places without any crowding of people or in stand-alone buildings.

241. It is permitted to install vessels:

1) in the rooms adjacent to industrial buildings provided they are separated from the building by a bearing wall with the structural strength determined in the design documentation with due regard for the maximum possible load which can occur in case of breakage (accident) of the vessels;

2) in the process rooms including boiler houses in any cases provided in the project with due regard for design standards for these facilities in relation to vessels that cannot be installed outside the process rooms due to the process conditions or operating conditions;

3) buried subject to accessibility of the valves and protection of the vessel walls against soil corrosion and stray current corrosion.

242. It is not permitted to install vessels in public and amenity buildings and the adjacent rooms as well as in any buildings and rooms where operation of vessels is not provided or prohibited.

243. Installation of vessels shall eliminate the possibility for their tipping.

244. Installation of vessels shall provide for the possibility of their inspection, repair and cleaning both from inside and outside.

Platforms and staircases shall be arranged in order to facilitate maintenance of vessels. Cradles and other devices may be used for inspection and repair of vessels. These devices shall not impair strength and stability of vessels, and their welding onto the vessel shall be performed in accordance with the requirements of these Rules.

Technical inspection of vessels

245. Vessels covered by these Rules shall be subject to technical examination after installation prior to putting into operation, regularly in the course of operation and also to unscheduled examination in case of necessity.

Technical examination includes checking of the documentation, exterior and interior inspection of the vessel in all accessible places, hydraulic (pneumatic) testing and recording of the technical examination results.

246. Technical examination of vessels shall be performed by the technical examination commission for pressure vessels appointed by the organizational and administrative act issued by the head of the vessel owner organization (hereinafter - the vessel technical examination commission).

The vessel technical examination commission shall include:

1) the employee of the vessel owner organization appointed by the company-wise organizational and administrative act in order to perform surveillance (control) of technical condition and operation of pressure vessels (hereinafter - the surveillance (control) person) - chairman of the commission;

2) the person responsible for operability and safe operation of vessels;

3) other workers of the vessel owner organization as well as workers of the installation, expert organization and any other organizations (in case of necessity).

247. Scope, methods, rejection standards and frequency of technical examinations of vessels (except for cylinders) shall be determined by the vessel manufacturing organization and specified in their operation manuals (guidelines).

If no such instructions are presented in the operation manuals (guidelines) technical examination shall be performed in accordance with the requirements specified in Table 9 of these Rules; scope and methods of non-destructive control for the basic metal and weld joints shall be defined by the operating organization taking into account the solutions for the vessel service life extension.

Table 9

Frequency of technical examinations for vessels

248. Technical examination of cylinders shall be performed in accordance with the procedure approved by the cylinder developing organization and containing the rejection standards, and frequency of examination shall be at least equal to the frequency specified in Table 10 of these Rules.

Table 10

Frequency of technical examinations for cylinders

249. Technical examination of any vessels inaccessible (or accessible to the limited extent) for regular control due to their design peculiarities or any other reasons shall be performed through the use of remote devices and non-destructive methods for control of metal and weld joints specified in the vessel operation manual (guideline). In case no such instructions are presented the operating organization (with involvement of an expert organization or the vessel developing organization where necessary) shall develop the technical examination guidelines.

250. Exterior and interior inspection shall be performed in order:

1) in the course of original examination - to confirm that the vessel is installed in accordance with these Rules and the design and engineering documentation and that the vessel and its components have no damages;

2) in the course of regular and unscheduled examinations - to define operability of the vessel and possibility for its further operation.

Hydraulic testing shall be performed in order to check strength of the vessel components and leak-tightness of joints. Vessels shall be presented for hydraulic testing with all valves and safety devices installed.

251. Prior to technical examination the vessel shall be shut down, cooled (heated), the working medium shall be drained, and plugs shall be installed to isolate the vessel from all pipelines connecting it to the pressure source or any other vessels.

In case the vessels contained any harmful substances referred to hazard classes 1 and 2 with regard to their impact on the human organism these vessels shall be subject to careful treatment (neutralization, degassing) prior to performance of any works inside vessels as well as prior to their interior inspection in accordance with the guidelines on safe work practices approved by the operating organization.

Lining, insulation and other types of anti-corrosion protection shall be fully or partially removed in case of any signs indicating the possibility of any material defects in the load-bearing structural components of vessels (non-tightness of the lining, rubber coating bulges, insulation soaking signs). Electric heating and drive of the vessel shall be switched off.

252. Unscheduled technical examination of vessels in operation shall be performed in the following cases:

1) if the vessel has been out of operation for more than 12 months;

2) if the vessel has been dismantled and installed at a new place;

3) if any bulges or dents have been eliminated, or the vessel repair or refurbishment (retrofitting) with the use of welding or brazing of the pressure components has been performed;

4) prior to application of the protective coating on the vessel walls;

5) after an accident with the vessel or its pressure components in case such examination is necessary within the scope of the restoration works;

6) upon the request of the surveillance (control) person or any other members of the technical examination commission.

253. Technical examination of vessels shall be performed in special-purpose repair and testing centers, at filling stations as well as in the operating organization having the necessary base and equipment for the examination in accordance with the requirements of these Rules.

254. Results of the technical examination with indication of the maximum permissible vessel operation parameters (pressure) and the time limits for the next technical examination shall be recorded to the vessel certificate by the surveillance (control) person. The time limits for the next technical examination shall not exceed the vessel service life established by the manufacturing organization or the resolution of the operating organization approved by the developing organization, the main material research organization and the expert organization.

In case any additional testing and studies are carried out in the course of technical examination types and results of these tests and studies shall be recorded in the vessel certificate with indication of the sampling points or sections subjected to testing and also the reasons for additional testing.

255. A plate with indication of the registration number, permissible pressure and date of the next exterior and interior inspection and hydraulic testing shall be attached to the vessel (except for transportable cylinders with the capacity of up to 100 l) deemed suitable for further operation in the course of technical examination or the relevant inscription shall be applied on it.

256. In case any defects are revealed in the course of the vessel inspection or testing the faulty component inspection report shall be issued.

Scope and contents of the faulty component inspection report shall comply with the requirements of federal rules and regulations in the field of atomic energy use establishing the rules for control of the basic metal, weld joints and deposited surfaces during operation of equipment, pipelines and other components of nuclear power plants.

In this case the possibility for further operation of the equipment with reduced parameters shall be permitted with due regard for the process in which the equipment is used and also shall be confirmed by strength calculations taking into account the nature and size of defects and determination of the remaining lifetime (in case of necessity). If the equipment is brought to the operation mode with reduced parameters the throughput capacity of safety valves shall be checked by the relevant calculations; they should be also adjusted (with due regard for the reduced parameters) or replaced (in case of negative results of the throughput capacity calculations).

Resolution on the possibility and time limits for the pressure equipment operation with reduced parameters shall be recorded to the vessel certificate by the technical examination commission chairman with indication of the reasons for reduction of the permissible parameters and attachment of the supporting documents (results of diagnostics and calculations).

257. In case it is defined by analysis of the defects revealed in the course of the technical examination that their occurrence is related to the equipment operation mode in this operating organization or peculiarities (drawbacks) of this equipment type design the chairman of the technical examination commission shall inform the chief executive officer of the operating organization about the necessity for unscheduled technical examination of all equipment operated in this organization under the same mode or all equipment of the same design.

258. In case it is revealed in the course of technical examination that the vessel is dangerous for further operation due to the existing defects or violations of these Rules operation of the vessel shall be prohibited by the resolution of the technical examination commission.

259. Subsequent to installation at the place of operation and prior to backfilling the liquefied gas tanks may be subject only to exterior inspection provided that not more than 12 months have passed since the insulation application and no welding has been used in the course of their installation.

260. All defects reducing the vessel strength shall be revealed in the course of exterior and interior inspection.

Individual corrosion cavities, mechanical damages (grooves, scratches, nicks) with the size in radial axis not exceeding half of the sealing surface width and depth not reducing the residual metal thickness beyond the design value shall be permitted on the sealing surfaces (flanges) of the vessel.

In this case special attention shall be paid to detection of the following defects:

1) on the vessel surfaces - cracks, ruptures, corrosion of walls (especially in the beading and cutting areas), bulges, buckles, honeycombs;

2) in weld seams - welding defects, ruptures, erosions;

3) in vessels with surfaces protected against corrosion - breakage of the lining including any loss of the lining layers integrity, cracks in the rubber, lead or other coating, enamel chipping, cracks and bulges in the plating layer, damages of the vessel wall metal at the areas of external protective coating;

4) in steel-plastic and non-metal vessels - lamination and rupture of reinforcing fibers exceeding the established limits.

261. The commission or person performing technical examination may demand removal (complete or partial) of the protective coating in case of necessity.

262. Prior to inspection vessels with the height exceeding 2 m shall be equipped with the necessary devices enabling safe access to all parts of the vessel.

263. Hydraulic testing of vessels shall be carried out only in case of satisfactory results of exterior and interior inspection.

264. The technical examination date for the vessel shall be defined by the vessel owner organization. In this case the established examination date shall not be later than the date specified in the vessel certificate. The technical examination time limits may be extended via an administrative act of the operating organization but not more than by three months with due regard for technical condition of the vessel based on the results of the previous technical examination.

In case of any unscheduled technical examination the reason for such examination shall be indicated in the vessel certificate.

265. Administration of the owner organization shall arrange preparation of the vessel for technical examination.

266. Vessels where impact of the medium can cause deterioration of chemical composition and mechanical properties of metal as well as vessels with the wall temperature exceeding 450 °C during operation shall be subject to metal condition control in the course of examination in accordance with the guidelines approved by the operating organization.

267. For vessels with expired specified service life established in the design and engineering documentation by the manufacturing organization or with extended specified service life based on the RD approved by the operating organization and the relevant technical statement the scope, methods and frequency of technical examination shall be defined with due regard for the results of technical diagnostics and determination of the residual lifetime performed by the operating organization or any specialized organization according to its decision.

268. In case it is defined by analysis of the defects revealed in the course of the vessel technical examination that their occurrence is related to the vessel operation mode in this operating organization or characteristic for this vessel design the administration of the vessel owner organization shall arrange unscheduled examination of all vessels installed in this operating organization and operated under the same mode or all vessels of the same design respectively.

269. After original technical examination the vessel shall be subject to registration in accordance with the requirements of federal rules and regulations in the field of atomic energy use establishing the rules of conformity assessment for the products subject to the requirements related to safety assurance in the field of atomic energy use.

VII. Supervision, service and maintenance

during operation of vessels

Organization of supervision

270. Administration of the vessel owner organization shall ensure maintenance of the vessels in good operating conditions and their safe operation as well as performance of the following arrangements:

1) appointment of the person (persons) responsible for good operating condition and safe operation of vessels as well as the surveillance (control) person (persons) from among the specialists having passed training and knowledge checks by a company-wise organizational and administrative act; the number of surveillance (control) persons shall be defined on the basis of the time required to perform the duties of these persons as per the job description;

2) definition of the positions (professions) of the workers that may be admitted to the vessel maintenance and training in accordance with the program approved by the operating organization and appointment of the operating personnel from among its workers having passed training, knowledge checks with regard to the guidelines, practical training and having certificates of professional competence and permits for maintenance of vessels;

3) development and approval of the operation guideline for the process system including the vessels;

4) the guideline with the statement of understanding shall be available at the workplaces of the operating personnel;

5) organization of regular checks of the personnel's knowledge with regard to the vessel operation manual (guideline);

6) establishment of the procedure for the personnel responsible for maintenance of the vessels to carry out supervision over the equipment in their care by inspection, actuation verification for valves, instrumentation, safety and interlock devices and maintenance of the vessels in good operable conditions; results of the inspection and verification shall be registered in the shift log sheet;

7) arrangement of the procedure and frequency for checking of knowledge with regard to these Rules for the management personnel and specialists;

8) arrangement of technical examinations within the established time limits;

9) provision of the required documentation for the specialists in order to ensure safe operation of the vessels.

Service and maintenance of vessels

271. Persons not younger than 18 years trained in accordance with the program established by the operating organization, having passed knowledge checks and possessing the permits for vessel maintenance issued in accordance with the procedure established by the operating organization shall be admitted to service and maintenance of vessels.

272. Training of the vessel maintenance personnel shall be carried out in training centers as well as at the course in organizations provided that they have the necessary conditions for training.

Knowledge checks shall be carried out by the commission of the operating organization (hereinafter - the knowledge checking commission); composition of the commission shall be defined in the organizational and administrative act of the operating organization.

273. Knowledge checks and documentation of their results shall be performed in accordance with the procedure established by the operating organization:

1) for the vessel maintenance personnel - at least once per 12 months;

2) for the management personnel and other specialists engaged in vessel operation - at least once per three years.

Unscheduled checks of knowledge shall be performed in the following cases:

1) in case of any violation of these Rules by the worker;

2) according to resolution of the operating organization management;

3) upon request of the surveillance (control) person;

4) on transfer of the worker from one organization to another;

5) off-the-job period exceeding six months;

6) after any incident or emergency situation occurred through the fault of the worker.

In case of any modifications introduced to the vessel operation manual (guideline) the personnel shall be familiarized with them against written acknowledgment.

In case of off-the-job period exceeding six months the vessel maintenance personnel shall pass practical training in order to recover practical skills prior to knowledge check.

274. Results of the operating personnel's knowledge checks shall be registered in the protocol signed by the knowledge checking commission chairman and members.

The protocol number and the results of knowledge checks shall be recorded in the certificates of competence signed by the commission chairman and stamped.

The format of certificates shall be defined by the operating organization.

275. Admittance of the personnel to unsupervised maintenance of vessels shall be arranged through the order (directive) of the vessel owner organization.

276. For vessels (autoclaves) with quick-detachable covers the procedure for storage and application of the labeled key shall be specified in the vessel operation manual (guideline).

277. The vessel owner organization shall develop the connection diagram for the vessel with indication of the pressure source, parameters, the working medium, valves, controls and instrumentation, automatic control devices, safety and interlock devices.

Forced (emergency) shutdown of the vessel

278. The vessel shall be shut down immediately in the following cases:

1) if the pressure in the vessel has increased above the permissible value and is not reducing in spite of all measures taken by the personnel;

2) if any malfunctions of safety devices are detected;

3) if any loss of leak-tightness and distortion of the physical dimensions is detected in pressure vessels;

4) malfunction of the pressure gage and impossibility to determine the pressure through the use of any other instruments;

5) liquid pressure drop below the permissible value in fire-heated vessels;

6) failure of all liquid level indicators;

7) malfunction of safety interlock devices specified in the design and engineering documentation;

8) breakout of a fire posing an immediate threat to the pressure vessel;

9) if any failures of the fasteners between the vessel and the foundation or support are detected;

10) in any other cases prescribed in the vessel operation manual (guideline).

The procedure for emergency shutdown of the vessel and its subsequent putting into operation shall be specified in the operation manual (guideline).

279. The causes of the emergency vessel shutdown shall be recorded in the shift (in-service) log sheet.

Repair and refurbishment (retrofitting) of vessels

280. In order to maintain the vessel in good operating condition the administration of the owner organization shall arrange timely repair of vessels in accordance with the schedule of preventive maintenance (hereinafter - SPM). The SPM system shall be selected by the vessel owner organization.

Occupational safety rules for operation of electrical installations effective in the operating organization shall be adhered to in the course of repair works.

281. SPM and refurbishment (retrofitting) of vessels in the course of operation shall be performed by the vessel owner organization or any engaged specialized organizations in accordance with the requirements of these Rules and the vessel design and engineering documentation.

Repair and refurbishment (retrofitting) of pressure vessels and their components through the use of welding shall be performed in accordance with the technique developed prior to commencement of the works by a specialized organization.

282. The quality control system (incoming, in-process and acceptance control) assuring performance of the works in accordance with the requirements of these Rules and the design and engineering documentation may be applied in the course of repair and refurbishment (retrofitting) of vessels operated at nuclear facilities.

Results of the repair and refurbishment (retrofitting) shall be recorded in the vessel certificate.

283. Repair and refurbishment (retrofitting) of vessels and their components under overpressure is not permitted.

284. Prior to commencement of works inside any vessel connected to other operating vessels via a common pipeline the vessel shall be isolated with plugs or disconnected. Disconnected pipelines shall be plugged.

The vessel shall be shut down for repair or refurbishment (retrofitting) in accordance with a work permit with adherence to the requirements of the operation manual (guideline).

285. Plugs used for the vessel isolation and installed between flanges shall have labeling (with indication of the permissible (design) pressure and nominal diameter) and a protruding part (shank) aimed to define presence of the plug.

For welded pipelines where it is impossible to install plugs disconnection of the pipeline shall be arranged through the use of two gate valves installed in series. A drain device connected directly to the atmosphere shall be installed between them. In individual cases when it is impossible to disconnect the pipeline for repair with two gate valves installed in series  the repaired section may be isolated through the use of one gate valve subject to permit of the chief engineer of the organization. In this case no steaming (leakage) through the drain to atmosphere opened for the period of repair works shall be present. In case the pipelines are isolated with one gate valve from the operating equipment with the water temperature not exceeding 45 °C no permit of the chief engineer is required for such isolation.

286. In case of any works inside the vessel (including interior inspection, repair and cleaning) safe lighting fixtures with the voltage not exceeding 12 V and in explosion-hazardous environment explosion-proof lighting fixtures shall be used. In case of necessity analysis of air for absence of any harmful or other substances exceeding the maximum permissible concentrations shall be performed.

Works inside the vessel shall be performed in accordance with the work permit defining inter alia safe conditions for the works inside the vessel.

Extension of the specified lifetime of vessels

287. The specified service life of pressure vessels may be extended subsequent to technical diagnostics performed by the operating organization (or any specialized organization according to its decision) within the scope defined in the regulatory documents. Decision on the service life extension (or termination of operation) shall be taken by the operating organization. Results of the vessel service life extension shall be recorded in the vessel certificate.

The technical diagnostics materials shall contain technical examination results for the vessel, the remaining lifetime assessment, reliability and strength calculations confirming the possibility to extend the specified vessel lifetime as well as any reports confirming the possibility for the vessel to perform its functions within the extended service life in compliance with all safety requirements, metal condition inspection reports and in-service metal inspection programs developed for the additional lifetime.

The above-mentioned requirements shall not be applicable to the vessels with their service life extended prior to entry of these Rules into force.

VIII. Additional requirements for cylinders

General requirements

288. Cylinders shall have faucets tightly screwed into the neck holes or flow and filling nozzles of special-purpose cylinders without any necks.

289. Cylinders for compressed, liquefied and dissolved gases with the capacity exceeding 100 l shall have certificates in accordance with the format given in Appendix 2 to these Rules.

290. Safety valves shall be installed on the cylinders with the capacity exceeding 100 l. In case the cylinders are installed in groups a safety valve may be provided for the entire group of cylinders.

291. Side nozzles of the faucets for cylinders (except for acetylene ones) filled with hydrogen and other flammable gases shall have lift-hand thread and for cylinders filled with oxygen and other non-flammable gases - right-hand thread.

In the course of operation a gas pressure reducer shall be connected to the faucet of a cylinder with dissolved acetylene through the use of a collar or a thrust screw.

292. Faucets for cylinders with acetylene and propane shall be made of steel. Application of copper alloys with copper content exceeding 65% is not permitted.

Faucets of cylinders with oxygen shall be screwed in with the use of sealing materials not capable of ignition in oxygen medium.

293. The following data shall be stamped and visible on the top spherical section of each cylinder:

1) trademark of the manufacturing organization;

2) cylinder number;

3) actual weight of an empty cylinder, kg: for cylinders with the capacity of up to 12 l inclusive - within the accuracy of 0.1 kg; of more than 12 and up to 55 l inclusive - within the accuracy of 0.2 kg; weight of cylinders with the capacity exceeding 55 l shall be specified in accordance with the RD for their manufacturing;

4) date (month, year) of manufacture and year of the next examination;

5) operating pressure P, MPa;

6) hydraulic testing pressure P_t, MPa;

7) capacity of cylinders, l: for cylinders with the capacity of up to 12 l inclusive - the rated one; for cylinders with the capacity of more than 12 and up to 55 l inclusive - actual one within the accuracy of 0.3 l; for cylinders with the capacity exceeding 55 l - in accordance with the RD for their manufacturing;

8) stamp of the quality control department (hereinafter - the QCD) of the manufacturing organization, round in shape with the diameter of 10 mm (except for standard cylinders with the capacity exceeding 55 l);

9) number of the standard for cylinders with the capacity exceeding 55 l.

Height of symbols on the cylinders shall be at least 6 mm and on the cylinders with the capacity exceeding 55 l - at least 8 mm.

Weight of cylinders except for acetylene cylinders shall be specified with due regard for weight of the applied paint, the cap ring and the base (if any are provided in the design) but without weight of the faucet and the cap.

For cylinders with the capacity of up to 5 l or with the wall thickness of less than 5 mm the nominal data may be stamped on a plate soldered to the cylinder or inscribed with enamel or oil paint.

294. Cylinders for dissolved acetylene shall be filled with porous mass and solvent in the volume specified in the engineering documentation for the cylinder. The organization filling the cylinders with porous mass shall be responsible for quality of porous mass and correct filling of the cylinders. The organization filling the cylinders with solvent shall be responsible for quality of solvent and its proper dosing.

Subsequent to filling of the cylinder with porous mass and solvent the tare weight (weight of the cylinder without the cap but with porous mass, solvent, the base, the ring and the faucet) shall be stamped on its neck.

295. External surface of cylinders shall be painted in accordance with Table 11 of these Rules.

Oil, enamel or nitrocellulose paints shall be used to paint cylinders and to make any inscriptions on them.

Painting of newly manufactured cylinders and application of inscriptions shall be performed by the manufacturing organizations and in the course of operation - by the filling stations or testing centers.

Color of paint job and text of inscriptions for cylinders used in special-purpose plants or intended to be filled with special-purpose gases shall be approved by the operating organization.

Table 11

Painting and inscriptions on cylinders

296. Inscriptions on cylinders shall be applied circumferentially at the length of at least 1/3 of the periphery and strips shall be allied along the entire periphery; in this case height of letters on cylinders with the capacity of more than 12 l shall be 60 mm and the strip width - 25 mm. Size of inscriptions and strips on cylinders with the capacity of up to 12 l shall be determined depending on the side surface area of the cylinders.

Examination of cylinders

297. Examination of cylinders shall be performed by filling stations and testing centers of the gas facilities system subject to availability of:

1) process rooms as well as equipment ensuring the possibility for proper examination;

2) order on appointment of the persons responsible for examination from among the specialists of the organization having passed the required training;

3) cylinder technical examination guidelines.

298. Verification of the manufacturing quality, examination and acceptance of the cylinders shall be performed by the QCD specialists of the manufacturing organization in accordance with the requirements of the RD for manufacturing.

The testing pressure value and time of the cylinder exposure to the testing pressure shall be specified in the design and engineering documentation; in this case the testing pressure shall be at least equal to one-and-a-half operating pressure.

299. Examination of cylinders except for acetylene cylinders shall include:

1) inspection of the interior (except for cylinders for liquefied hydrocarbon gas (propane-butane) with the capacity of up to 55 l) and exterior surface of cylinders;

2) weight and capacity verification;

3) hydraulic testing.

Verification of weight and capacity shall not be performed for seamless cylinders with the capacity of up to 12 l inclusive and more than 55 l as well as welded cylinders regardless of their capacity.

300. In case of satisfactory results the organization performing the examination shall apply its round stamp with the diameter of 12 mm to the cylinder and also specify the dates of the performed and the next examination (in the same line with the stamp). Technical examination results for cylinders with the capacity exceeding 100 l shall be recorded in the cylinder certificate. No stamps shall be applied to the cylinders in this case.

301. Examination results for cylinders (except for acetylene cylinders) shall be recorded by the person who has performed examination of the cylinders to the test log sheet containing inter alia the following columns:

1) trademark of the manufacturing organization;

2) cylinder number;

3) cylinder manufacturing date (month, year);

4) date of the performed and the next examination;

5) cylinder weight stamped on the cylinder, kg;

6) cylinder weight determined in the course of examination, kg;

7) cylinder capacity stamped on the cylinder, l;

6) cylinder capacity determined in the course of examination, l;

9) operating pressure P, MPa;

10) record of the cylinder serviceability;

11) signature of the person who has performed examination of the cylinder.

302. Examination of acetylene cylinders shall be performed at acetylene filling stations at least once per 5 years and include the following:

1) exterior surface inspection;

2) porous mass inspection;

3) pneumatic testing.

303. Condition of porous mass in acetylene cylinders shall be checked at filling stations at least once per 24 months.

In case the condition of porous mass is satisfactory the following data shall be stamped on each cylinder:

1) year and month of the porous mass inspection;

2) stamp of the filling station;

3) stamp with the diameter of 12 mm and letters "Pm" confirming the porous mass inspection.

304. Acetylene cylinders filled with porous mass shall be subject to testing with nitrogen under the pressure of 3.5 MPa in the course of examination.

Purity of nitrogen used for testing of cylinders shall be at least 97% by volume.

305. Examination results for acetylene cylinders shall be recorded in the test log sheet containing the following column:

1) cylinder number;

2) trademark of the manufacturing organization;

3) cylinder manufacturing date (month, year);

4) signature of the person who has performed examination of the cylinder.

5) date of the performed and the next examination of the cylinder.

306. Visual inspection of cylinders shall be performed in order to detect any corrosion, cracks, blisters, dents and other defects on their walls (so that to define the cylinder suitability for further operation). Prior to inspection the cylinders shall be carefully cleaned and washed with water, and in case of necessity washed with the proper solvent or degassed.

307. Cylinders with any cracks, blisters, dents, bulges, honeycombs and nicks with the depth exceeding 10% of the nominal wall thickness, ruptures and chips detected during inspection of the exterior and interior surface, wear of the neck thread and also cylinders without certain nominal data shall be rejected.

In case the ring on the cylinder neck is loosened the cylinder may be admitted for further examination subsequent to replacement of the ring or its fastening in accordance with the technique approved by the expert organization or the developing organization.

Cylinders with slanting or loose base fitting shall not be permitted for further examination without the base refitting.

308. Capacity of the cylinder shall be determined by the difference between the weight of the cylinder filled with water and the weight of the empty cylinder or through the use of measuring boxes.

309. Rejection of cylinders based on the results of their exterior and interior inspection shall be performed in accordance with the RD for their manufacturing.

Operation of the cylinders with any data prescribed in these Rules missing shall be prohibited.

The loose ring on the neck or the base shall be fastened or replaced prior to the cylinder examination.

310. Standard seamless cylinders with the capacity of 12 to 55 l shall be rejected and withdrawn from operation in case of their weight decrease by 7.5% and more and also in case of their capacity increase by more than 1%.

311. Rejected cylinders regardless of their purpose shall be made inoperable (by making notches on the neck thread or drilling holes in the casing) in order to prevent the possibility of their further use.

312. Examination of cylinders shall be carried out in separate specially equipped rooms. Air temperature in these rooms shall be at least 12 °C.

Electric lighting with the voltage not exceeding 12 V may be used for interior inspection of cylinders.

For inspection of cylinders filled with explosive gases the hand lamp fittings and plug connection shall be explosion-proof.

313. Gas-filled cylinders placed for long-term warehouse storage shall be subject to examination when the next date of periodic examinations comes on a selective basis in the quantity of at least 5 cylinders from a batch of up to 100 cylinders, 10 - from a batch of up to 500 cylinders and 20 - from a batch of more than 500 cylinders.

In case the examination results are satisfactory the storage period for the cylinders shall be established to be not more than two years. Results of selective examination shall be recorded in the relevant report.

In case the examination results are unsatisfactory repeated examination of the cylinders in the same quantity shall be performed.

In case the repeated examination results are unsatisfactory further storage of the entire batch of cylinders is not permitted; gas shall be removed from the cylinders, and then the cylinders shall be subject to technical examination (each cylinder separately).

Operation of cylinders

314. Operation, storage and transportation of cylinders shall be performed in accordance with the requirements of the duly approved guidelines.

315. Gas cylinders may be stored both in special-purpose rooms and outdoors; in the latter case they should be protected against precipitation and sunlight.

Warehouse storage of cylinders with oxygen and flammable gases in the same room is prohibited.

316. Gas cylinders installed in the rooms shall be located at the distance of not less than 1 m from convectors, other heating devices and furnaces and not less than 5 m from heat sources with open flames.

317. In the course of cylinder operation it is prohibited to exhaust the gas in them to the full extent. Residual gas pressure in the cylinder shall be at least 0.05 MPa.

318. Release of gas from cylinders to any tanks with lower operating pressure shall be arranged via a reducer intended for this gas and painted with the relevant color.

The low pressure chamber of the reducer shall have a pressure gage and a spring safety valve set for the relevant permissible pressure in the tank where gas is supplied.

319. In case it is impossible to release the gas from cylinders at the place of consumption because of the faucet failure the cylinders shall be returned to the filling station. Gas shall be released from such cylinders at the filling station in accordance with the guidelines.

320. Workers filling the cylinders with compressed, liquefied and dissolved gases shall maintain the cylinder filling log sheet with indication of the following:

1) date of filling;

2) cylinder number;

3) examination date;

4) weight of gas (liquefied) in the cylinder, kg;

5) signature of the person who has filled the cylinder.

In case cylinders are filled with different gases at the same station a separate filling log sheet shall be maintained for each gas.

321. Filling of cylinders with gas shall be performed in accordance with the guidelines developed and approved by the manufacturing organization with due regard for the gas properties, local conditions and requirements of the standard operating procedure for cylinder filling with gas.

Filling of cylinders with liquefied gases shall comply with the standards specified in Table 12 of these Rules.

Table 12

Standards for filling of cylinders with liquefied gases

The filling standards for any gases not specified in this table shall be established in the standard operating procedures of the filling stations.

322. Cylinders filled with gas shall be fastened and tightly connected to the filling ramp.

323. It is prohibited to fill cylinders with gas in the following cases:

1) expiry of the specified examination time limits;

2) expiry of the time limits for porous mass inspection;

3) damage of the cylinder casing;

4) faucet malfunction;

5) absence of the proper painting or inscriptions;

6) absence of gauge gas pressure;

7) absence of the required stamps.

Filling of the cylinders without gauge gas pressure shall be performed subsequent to their preliminary inspection in accordance with the guidelines of the filling organization (filling station).

324. Refitting of bases and cap rings, replacement of faucets shall be performed at the cylinder examination stations.

Leak-tightness of faucets shall be verified under the operating pressure subsequent to any repair with their disassembly.

325. Bases shall be fitted to the cylinders only after gas release, screw-out of faucets and proper degassing of the cylinders.

Cleaning and painting of cylinders filled with gas as well as fastening of their neck rings is prohibited.

326. Cylinders with toxic gases shall be stored in special-purpose enclosed rooms; arrangement of these rooms is prescribed in the regulatory documents of the operating organization.

327. Filled cylinders with fitted bases shall be stored in vertical position. To prevent the cylinders from falling they shall be installed into specially equipped sockets, cages or enclosed with a barrier.

328. Cylinders without bases may be stored in horizontal position on wooden frames or racks. In case of outdoor storage cylinders with bases may be stacked with spacers made of ropes, wooden bars or rubber between horizontal rows.

When the cylinders are stacked, the stack height shall not exceed 1.5 m. Faucets of cylinders shall face the same side.

329. Warehouses for storage of gas-filled cylinders shall be single-storeyed with lightweight roof slabs and without any attics. Walls, partitions, roof slabs of gas warehouses shall be made of non-combustible materials with the fire resistance rating of at least II; windows and doors shall open outwards. Window and door panes shall be non-transparent or covered with white paint. Height of storage rooms for cylinders shall be at least 3.25 m from the floor to the bottom protruding elements of the roof slab.

Warehouse floors shall be smooth with anti-slip surface, and in warehouses for cylinders with flammable gases - with the surface made of materials that prevent sparking in case of any object impact.

330. Equipment of warehouses for cylinders with flammable gases shall comply with the regulatory documents for explosion-hazardous rooms.

331. Any documents regulating the rules for handling of cylinders under storage shall be displayed in the warehouses.

332. Warehouses for gas-filled cylinders shall have natural or forced ventilation in accordance with the requirements of sanitary design standards.

333. Warehouses for cylinders with explosion- and fire-hazardous gases shall be located within the lightning protection area.

334. A storage room for cylinders shall be divided into compartments by fire-resistant walls; each compartment shall contain not more than 500 cylinders (with the capacity of 40 l) with flammable or toxic gases and not more than 1000 cylinders (with the capacity of 40 l) with non-flammable and non-toxic gases.

Compartments for storage of cylinders with non-flammable and non-toxic gases may be separated by fire-resistant partitions with the height of at least 2.5 m and openings for passage of people and apertures for mechanical appliances. Each compartment shall have an independent exit.

335. Distances between warehouses for gas-filled cylinders and between warehouses and adjacent industrial buildings shall be defined in the project and comply with the city-planning standards.

336. Transportation of cylinders at the filling and gas consumption stations shall be arranged through the use of special-purpose trolleys.

337. Gas-filled cylinders shall be transported by sprung vehicles or power trucks in horizontal position with spacers between the cylinders.

Wooden blocks with cut pockets for cylinders and also rope or rubber rings with the thickness of at least 25 mm (two rings per a cylinder) or any other materials preventing the cylinders from hitting each other may be used as spacers. For the purpose of transportation all cylinders must be placed with faucets directed one way.

It is permitted to transport cylinders in special-purpose containers and also without containers in vertical position with mandatory spacers between them and guards to prevent potential falling.

338. Filled cylinders may be stored without protective caps prior to their delivery to the consumers.

Appendix 1

to federal rules and regulations

in the field of atomic energy use

"Rules for arrangement

and safe operation of

pressure vessels

for nuclear

facilities" approved by Order of

of the Federal Environmental,

Industrial and Nuclear Supervision Service

dated 2 March 2018 No. 93

TERMS AND DEFINITIONS

Cylinder - a vessel with one or two necks for installation of faucets, flanges or nozzles intended for transportation, storage and use of gases (compressed, liquefied or dissolved  under pressure).

Bottom - an integral part of a vessel casing enclosing the inner cavity from the end side.

Casing - the main assembly unit of a vessel composed of shells and bottoms.

Cover - a detachable part covering the inner cavity of a vessel or a manhole aperture.

Manhole - a device providing access to the inner cavity of a vessel.

Shell - cylindrical cladding of a closed-section vessel opened at butt ends.

Tank - a stationary vessel intended for storage of gaseous, liquid and other substances.

Vessel jacket - a heat exchanging device consisting of an envelope enclosing a vessel casing or any part thereof and, together with vessel casing wall, forming a cavity filled with heat transfer medium.

Vessel - a leak-tight closed container intended for chemical, thermal and any other processes and also for storage and transportation of gaseous, liquid and other substances. The vessel boundary is formed by the inlet and outlet nozzles (inclusive).

Appendix 2

to federal rules and regulations

in the field of atomic energy use

"Rules for arrangement

and safe operation of

pressure vessels

for nuclear

facilities" approved by Order of

of the Federal Environmental,

Industrial and Nuclear Supervision Service

dated 2 March 2018 No. 93

REQUIREMENTS FOR THE CONTENTS OF THE VESSEL AND CYLINDER CERTIFICATE

А. Vessel certificate

The vessel certificate shall include the following information (in the scope to be defined by the manufacturing organization depending on the vessel type).

1. General information, including:

1) name and address of the manufacturing organization;

2) manufacturing (production) date;

3) serial number;

4) design service life.

2. Information on the technical characteristics and parameters:

1) operating, design and testing pressure, MPa;

2) operating temperature of the working medium, °C;

3) design wall temperature, °C;

4) minimum permissible negative wall temperature, °C;

5) working medium;

6) working medium group;

7) corrosion (erosion) allowance, mm;

8) capacity, m³;

9) weight of the empty vessel, kg;

10) maximum weight of filling medium, kg.

3. Information on the main parts (including quantity, dimensions, materials, welding (brazing)).

4. Information on any nozzles, flanges, covers, fasteners (including quantity, dimensions, materials).

5. Information on safety devices, the main valves, controls and instrumentation, safety instruments (including quantity, nominal diameter, design pressure, casing material, places of installation).

6. Pictures, diagrams, drawings of the vessel and other documents (consolidated list of factory modifications, packing list, specifications with basic dimensions of the assembly units).

7. Any other information ensuring safe operation of the vessel, including reports on the technical examination results, data on any replacement and repair of the main vessel components and valves.

B. Cylinder certificate

The cylinder certificate shall include the following information (in the scope to be defined by the manufacturing organization depending on the cylinder type).

1. General information, including:

1) name and address of the manufacturing organization;

2) manufacturing (production) date;

3) cylinder designation;

4) medium for which the cylinder is intended;

5) serial number.

2. Information on the technical characteristics and parameters:

1) operating pressure, MPa;

2) testing pressure, MPa;

3) basic dimensions of the cylinder, drawing of the cylinder;

4) capacity, l;

5) weight, kg;

6) thread on the necks;

7) sealing of the necks;

8) operating temperature range, °C;

9) maximum number of fillings;

10) design service life from the date of manufacturing (production), years.

3. Requirements for transportation and storage of the cylinder.

4. Requirements for installation of the cylinder.

5. Requirements for operation of the cylinder.

6. Any other information ensuring safe operation of the cylinder including reports on the technical examination results.

Translator:                                                 

Переводчик:                                                 

                                                    Российская Федерация

                                                          Город Москва

                                        Десятого декабря две тысячи восемнадцатого года

Я, Домахина Алла Валерьевна, временно исполняющая обязанности нотариуса

города Москвы Король Виктории Алексеевны, свидетельствую подлинность подписи переводчика Златовратской Дарьи Борисовны. Подпись сделана в моем присутствии. Личность подписавшего документ установлена.

                Зарегистрировано в реестре: № 08/82-н/77-2018-

                Взыскано государственной пошлины (по тарифу): 100 руб.

                Уплачено за оказание услуг правового и технического характера: 200 руб.

                                                                                                              А.В. Домахина