GB/T 12234-2019Bolted bonnet steel gate valves for petroleum and natural gas industries (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard replaces GB/T 12234-2007 "Steel gate valve for connecting studs for oil and gas industry", and

The main technical contents of GB/T 12234-2007 are as follows.

--- Increased the nominal size of the DN650~DN1050 gate valve (see Chapter 1);

--- Increased the post-weld heat treatment requirements for the welding of the valve body end flange to the valve body (see 4.4.3);

--- Increased wall thickness and minimum stem size in the DN600~DN1050 size range (see 4.4.4, 4.10.2);

--- Increased the Class level corresponding to the nominal pressure of PN20, PN50, PN100, PN150 (see 4.4.4, 4.5.6, 4.10.2);

---Modified the requirements for the valve body and bonnet connection studs (see 4.7, 4.7 of.2007 edition);

---Modified the requirements for strength calculation of valve body and bonnet studs (see 4.7.3, 4.7.2 of.2007 edition);

---Modified the minimum diameter of the stem (see 4.10.2,.2007 version 4.4.6);

--- Increased the requirement to allow negative deviation size (see 4.10.2);

--- Increased requirements for valve stem microleak test (see 4.11.6);

--- Revised the requirements for packing and stuffing box letters (see 4.11, 4.11 of the.2007 edition);

--- Revised the material requirements and increased the hardness of the stem material (see 5.1.4, 5.5 of.2007).

This standard was proposed by the China Machinery Industry Federation.

This standard is under the jurisdiction of the National Valve Standardization Technical Committee (SAC/TC188).

This standard was drafted. Hefei General Machinery Research Institute Co., Ltd., China Nuclear Su Valve Technology Industrial Co., Ltd., Wuhan Boiler Group

Valve Co., Ltd., Shanghai Lianggong Valve Factory Co., Ltd., Global Valve Group Co., Ltd., Shangzheng Valve Group Co., Ltd., Yuanda Valve

1 Scope

This standard specifies the structure type, technical requirements, materials, test methods, inspection rules, markings, protection, packaging, storage and transportation of bolted bonnet steel gate valves for petroleum and natural gas industries (hereinafter referred to as the “gate valve”).

This standard is applicable to flanged or welded gate valves with nominal pressure of PN16 to PN420, nominal dimension of DN25 to DN1050, pressure class of Class150 to Class2500, nominal dimension of NPS1 to NPS42 at applicable temperature of -46°C to 550°C, including: rising stem thread and bracket form (lifting valve stem, non-lifting hand wheel) gate valves; metal sealing pair, wedge single-gate, wedge double-gate, parallel double-gate structure gate valves; gate valves with pressure self-sealing bonnet.

This standard may also serve as a reference for the gate valves with threaded connection and clamp connection at the end.

2 Normative references

The following referenced documents are indispensable for the application 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 150.3 Pressure vessels—Part 3: Design

GB/T 150.4 Pressure vessels—Part 4: Fabrication, inspection and testing, and acceptance

GB/T 152.4 Fasteners—Counterbores for hexagonbolts 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 798 Eye bolt

GB/T 5796 (all parts) Trapezoidal threads

GB/T 9113 Integral steel pipe flanges

GB/T 9124 Specification for steel pipe flanges

GB/T 12220 Industrial valves—Marking

GB/T 12221 Metal valves—Face to face, end to end, center to face and center to end dimensions

GB/T 12222 Multi-turn valve actuator attachments

GB/T 12224 General requirements for industrial steel valves

GB/T 26480 Valve inspection and testing

GB/T 26481 Valve test for fugitive emissions

JB/T 106 Valves marking and paint

JB/T 8858 Gate valve—Potential pressure life test regulation

NB/T 47013.2 Nondestructive testing of pressure equipment—Part 2: Radiographic testing

NB/T 47013.3 Nondestructive testing of pressure equipment—Part 3: Ultrasonic testing

NB/T 47013.4 Nondestructive testing of pressure equipment—Part 4: Magnetic particle testing

NB/T 47013.5 Nondestructive testing of pressure equipments—Part 5: Penetrant testing

SY/T 0599 Metallic material requirements on resistance to sulfide stress cracking and stress corrosion cracking for natural gas surface equipment

ISO 15848-1 Industrial valves—Measurement, test and qualification procedures for fugitive emissions—Part 1: Classification system and qualification procedures for type testing of valves

ISO 15848-2 Industrial valves—Measurement, test and qualification procedures for fugitive emissions—Part 2: Production acceptance test of valves

3 Type

The typical structure of the gate valve is shown in Figure 1.

Key:

1——body;

2——seat;

3——gate;

4——stem;

5——stud;

6——nut;

7——gasket;

8——nameplate; 9——rivets;

10——bonnet;

11——upper sealing seat;

12——packing;

13——cylindrical pin;

14——eye bolt;

15——nut;

16——packing sleeve; 17——packing plate;

18——stem nut;

19——nozzle;

20——stem nut gland;

21——hand wheel;

22——locknut;

23——bolt;

24——nut.

Figure 1 Typical structure diagram of the gate valve

4 Technical requirements