GB/T 12237-2021 in English

《GB/T 12237-2021石油、石化及相关工业用的钢制球阀》由TC188（全国阀门标准化技术委员会）归口，主管部门为中国机械工业联合会。

ChinaStandards.net is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.

This document is developed in accordance with the rules given in GB/T 1.1-2020 Directives for standardization—Part 1: Rules for the structure and drafting of standardizing documents.

This document replaces GB/T 12237-2007 Steel ball valves for petroleum, petrochemical and allied industries. In addition to a number of editorial changes, the following main technical changes have been made with respect to GB/T 12237-2007:

a) the applicable scope of the ball valve is expanded, and the pound class requirements, applicable structure and temperature requirements are added (see Clause 1, Clause 1 of the Edition 2007);

b) the overpressure requirements of body cavity are added (see 5.1.3);

c) the minimum sectional area requirements for connections between valve bodies are modified (see 5.6.8; 5.6.6 of Edition 2001);

d) the packing box requirements are deleted (5.12.2 of Edition 2007) ;

e) the limit requirements of operating mechanism are added (see 5.12.3);

f) the material requirements are modified (see Clause 6; Clause 6 of Edition 2007).

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. The issuing body of this document shall not be held responsible for identifying any or all such patent rights.

This standard was proposed by the China Machinery Industry Federation.

This document is under the jurisdiction of National Technical Committee 188 on Valve of Standardization Administration of China (SAC/TC 188).

The previous editions of this standard are as follows:

——It was first issue as GB/T 12237-1989 in 1989, and first revised in 2007;

——This is the second revision.

Steel ball valves for petroleum, petrochemical and allied industries

1 Scope

This document specifies the structural type, technical requirements, materials, test methods, inspection rules, markings, protection, packaging, storage and transportation of steel ball valves of elastic sealing pair for petroleum, petrochemical and allied industries.

This document is applicable to:

——Ball valves at flange connecting end and welded connecting end, with nominal pressure of PN16-PN100, nominal dimension of DN15-DN600, pressure class of Class150-Class600 and nominal dimension of NPS½-NPS 24;

——Ball valves at threaded connecting end and socket welding connecting end, with nominal pressure of PN16-PN140, nominal dimension of DN8-DN50, pressure class of Class150-Class800 and nominal dimension NPS¼ -NPS2;

——-Ball valves with full diameter and reduced diameter. Ball valves with floating ball structure and fixed ball structure;

——Applicable temperature: -46°C to 260°C.

Ball valves with metal and ceramic material sealing pair can be implemented by reference to this document.

2 Normative references

The following documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 150.4 Pressure vessels—Part 4: Fabrication, inspection and testing, and acceptance
GB/T 152.4 Fasteners—Counterbores for hexagon bolts and nuts
GB/T 196 General purpose metric screw threads—Basic dimensions
GB/T 197 General purpose metric screw threads—Tolerances
GB/T 228.1 Metallic materials - Tensile testing—Part 1: Method of test at room temperature
 
GB/T 7306.2 Pipe threads with 55 degree thread angle where pressure-tight joints are made on the threads—Part 2: Taper internal and external threads
GB/T 9124 (All parts) Steel pipe flanges
GB/T 12220 Industrial valves—Marking
GB/T 12221 Metal calves—Face to face, end to end, center to face and center to end dimensions
GB/T 12223 Part-turn valve actuator attachments
GB/T 12224 General requirements for industrial steel valves
GB/T 12228 General purpose industrial valves—Specification of carbon steel forgings
GB/T 12229 General purpose industrial valves—Specification of carbon steel castings
GB/T 12230 General purpose industrial valves—Specification of stainless steel castings
GB/T 20801.5 Pressure piping code—Industrial piping—Part 5: Inspection and testing
GB/T 26479 Fire test for soft-seated quarter-turn valves
GB/T 26480 Valve inspection and testing
GB/T 35741 Specification of stainless steel forgings for industrial valves
JB/T 106 Valves marking and paint
SY/T 7024 Technical code for field hardness test of metal materials used in highly hydrogen sulfide gas field

3 Terms and definitions
For the purposes of this document, the following term and definition apply.

3.1
conducting electrostatic design
structure to ensure continuous electrostatic conduction among valve body, ball and stem

3.2
fire resisting design
structure that can still maintain certain sealing performance requirements when the elastic sealing material is damaged by fire

4 Structural types

Typical structure of floating ball valve (one-piece type) is shown in Figure 1, typical structure of floating ball valve (two-piece type) is shown in Figure 2, and typical structure of fixed ball valve is shown in Figure 3.


Keys of index numbers:
1——valve body; 5——ball; 9——packing restrainer;
2——valve seat gland; 6——stem; 10——screw;
3——seal ring of valve seat gland; 7——stem packing; 11——handle.
4——seal ring of valve seat; 8——packing bushing;
Figure 1 Schematic diagram for typical structure of floating ball valve (one-piece type)


Keys of index numbers:
1——left valve body; 6——ball; 11——packing bushing;
2——stud; 7——stem; 12——packing restrainer;
3——nut; 8——stem thrust gasket; 13——screw.
4——valve body; 9——valve body gasket;
5——valve seats; 10——packing;
Figure 2 Schematic diagram for typical structure of floating ball valve (two-piece type)

Keys of index numbers:
1——valve body; 7——lower stem; 13——screw.
2——stud; 8——upper stem; 14——lower stem end cover;
3——nut; 9——seal ring; 15——seal ring;
4——left valve body; 10——packing; 16——bolt.
5——valve seats; 11——packing bushing;
6——ball; 12——packing restrainer;
Figure 3 Schematic diagram for typical structure of fixed ball valve (three-piece type)

Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Structural types
5 Technical requirements
5.1 Pressure-temperature rating
5.2 Structure length
5.3 Connecting end
5.4 Dimension of ball runner
5.5 Valve body
5.6 Connection between valve bodies
5.7 Anti-dropping structure of stem
5.8 Stem structure
5.9 Ball
5.10 Packing gland and bolts
5.11 Conducting electrostatic design
5.12 Operating mechanism
5.13 Fire resisting design
5.14 Non-destructive test
5.15 Pressure test of ball valve
5.16 Ordering requirements
6 Materials
6.1 Ball valve housing
6.2 Ball and valve seat
6.3 Stem
6.4 Connecting studs and bolts between valve bodies
6.5 Connecting bolts between packing gland and bonnet
6.6 Sealing materials
6.7 Packing sleeve and packing plate
6.8 Plug screw
6.9 Handle or handwheel
6.10 Hydrogen sulfide resistance
7 Test methods and inspection rules
7.1 Test methods
7.2 Inspection rules
8 Marking
8.1 Marking contents
8.2 Marking on valve body
8.3 Markings on the plate
8.4 Other markings
9 Protection, packaging, storage and transportation
Annex A (informative) Order contract data sheet