GB/T 21385-2025 Metal-seated ball valve English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS 13.220
CCS H 57
National Standard of the People's Republic of China
GB/T 21385-2025
Replaces GB/T 21385-2008
Metal-seated ball valve
金属密封球阀
Issue date: 2025-10-31 Implementation date: 2026-05-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms and Definitions
4 Structural Types
5 Technical Requirements
6 Materials
7 Test Methods
8 Inspection Rules
9 Marking and Nameplate
10 Protection, Packaging, Storage and Transportation
11 Supply Requirements
Appendix A (Informative) Metal-Seated Ball Valve Order Data Sheet
1 Scope
This document specifies the structural types, technical requirements, materials, test methods, inspection rules, marking, nameplates, and protection, packaging, storage, and transportation for metal-seated ball valves.
This document applies to the design, production, and inspection of metal-seated ball valves with nominal sizes DN15 to DN800 and nominal pressures PN16 to PN400, or nominal sizes NPS 1/2 to NPS 32 and nominal pressure classes Class 150 to Class 2500, suitable for temperatures from -29°C to 550°C, and for media including gases, liquids, and gas-solid, gas-liquid, solid-liquid, and gas-solid-liquid multiphase flows, with flanged, welded, or threaded connections.
2 Normative References
The contents of the following documents, through normative citations in this document, constitute essential provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including all amendments) applies.
GB/T 70.1 Hexagon socket head cap screws
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 897 Studs with nominal lengths equal to the nominal diameter (bm=1d)
GB/T 898 Studs with nominal lengths equal to 1.25 times the nominal diameter (bm=1.25d)
GB/T 901 Studs with equal lengths - Grade B
GB/T 4622 (all parts) Spiral wound gaskets for pipe flanges
GB/T 5782 Hexagon head bolts
GB/T 5783 Hexagon head bolts - Full thread
GB/T 6175 Hexagon nuts - Style 2
GB/T 7306 (all parts) 55° sealing pipe threads
GB/T 9124 (all parts) Steel pipe flanges
GB/T 9128 (all parts) Ring joint gaskets for steel pipe flanges
GB/T 12220 Industrial valves - Marking
GB/T 12221 Metal valves - Face-to-face and end-to-end dimensions
GB/T 12223 Part-turn valve actuator attachments
GB/T 12224 Steel valves - General requirements
GB/T 12228 General purpose valves - Carbon steel forgings
GB/T 12229 General purpose valves - Carbon steel castings
GB/T 12230 General purpose valves - Stainless steel castings
GB/T 12716 Pipe threads with pressure-tight joints
GB/T 13927 Industrial valves - Pressure testing
GB/T 35741 Technical conditions for stainless steel forgings for industrial valves
HG/T 20592 Steel pipe flanges (PN series)
HG/T 20615 Steel pipe flanges (Class series)
JB/T 6899 Fire test for valves
JB/T 7370 Flexible graphite braided packing
JB/T 7928 Industrial valves - Supply requirements
ISO 10497 Testing of valves - Fire type-testing requirements
3 Terms and Definitions
The following terms and definitions apply to this document.
3.1 Metal-seated Ball Valve
A ball valve with metal-to-metal sealing pair.
Note: The sealing pair refers to the valve seat sealing surface and the ball sealing surface.
4 Structural Types
Metal-seated ball valves (hereinafter referred to as "ball valves") are divided into floating ball valves and trunnion-mounted ball valves, with typical structures shown in Figures 1 to 3.
5 Technical Requirements
5.1 Pressure-Temperature Ratings
5.1.1 The pressure-temperature ratings of the ball valve body shall comply with the provisions of GB/T 12224.
5.1.2 The allowable pressure-temperature ratings of the ball valve are limited by the allowable working pressure, temperature, and pressure difference of the non-metallic sealing materials inside the valve. The allowable pressure-temperature ratings of the ball valve shall be determined by the smaller value between the pressure-temperature ratings of the non-metallic sealing material used and the pressure-temperature ratings of the ball valve body.
5.2 Face-to-Face and End-to-End Dimensions
The face-to-face and end-to-end dimensions of the ball valve shall comply with the provisions of GB/T 12221 or the requirements of the purchase order.
5.3 Connection Ends
5.3.1 Flanged connections shall comply with the provisions of GB/T 9124 (all parts) or HG/T 20592, HG/T 20615, or the requirements of the purchase order.
5.3.2 The surface roughness of the flange sealing connection faces shall comply with the provisions of GB/T 9124 (all parts) or the requirements of the purchase order.
5.3.3 Welded connections shall comply with the provisions of GB/T 12224 or the requirements of the purchase order.
5.3.4 The threads of internal threaded connections shall comply with the provisions of GB/T 7306 (all parts) and GB/T 12716, or the requirements of the purchase order.
5.4 Flow Passage of Ball Valves
The flow passages of full-bore and reduced-bore ball valves shall be circular, with the minimum diameters as specified in Table 1.
GB/T 21385-2025 Metal-seated ball valve English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS 13.220
CCS H 57
National Standard of the People's Republic of China
GB/T 21385-2025
Replaces GB/T 21385-2008
Metal-seated ball valve
金属密封球阀
Issue date: 2025-10-31 Implementation date: 2026-05-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms and Definitions
4 Structural Types
5 Technical Requirements
6 Materials
7 Test Methods
8 Inspection Rules
9 Marking and Nameplate
10 Protection, Packaging, Storage and Transportation
11 Supply Requirements
Appendix A (Informative) Metal-Seated Ball Valve Order Data Sheet
1 Scope
This document specifies the structural types, technical requirements, materials, test methods, inspection rules, marking, nameplates, and protection, packaging, storage, and transportation for metal-seated ball valves.
This document applies to the design, production, and inspection of metal-seated ball valves with nominal sizes DN15 to DN800 and nominal pressures PN16 to PN400, or nominal sizes NPS 1/2 to NPS 32 and nominal pressure classes Class 150 to Class 2500, suitable for temperatures from -29°C to 550°C, and for media including gases, liquids, and gas-solid, gas-liquid, solid-liquid, and gas-solid-liquid multiphase flows, with flanged, welded, or threaded connections.
2 Normative References
The contents of the following documents, through normative citations in this document, constitute essential provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including all amendments) applies.
GB/T 70.1 Hexagon socket head cap screws
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 897 Studs with nominal lengths equal to the nominal diameter (bm=1d)
GB/T 898 Studs with nominal lengths equal to 1.25 times the nominal diameter (bm=1.25d)
GB/T 901 Studs with equal lengths - Grade B
GB/T 4622 (all parts) Spiral wound gaskets for pipe flanges
GB/T 5782 Hexagon head bolts
GB/T 5783 Hexagon head bolts - Full thread
GB/T 6175 Hexagon nuts - Style 2
GB/T 7306 (all parts) 55° sealing pipe threads
GB/T 9124 (all parts) Steel pipe flanges
GB/T 9128 (all parts) Ring joint gaskets for steel pipe flanges
GB/T 12220 Industrial valves - Marking
GB/T 12221 Metal valves - Face-to-face and end-to-end dimensions
GB/T 12223 Part-turn valve actuator attachments
GB/T 12224 Steel valves - General requirements
GB/T 12228 General purpose valves - Carbon steel forgings
GB/T 12229 General purpose valves - Carbon steel castings
GB/T 12230 General purpose valves - Stainless steel castings
GB/T 12716 Pipe threads with pressure-tight joints
GB/T 13927 Industrial valves - Pressure testing
GB/T 35741 Technical conditions for stainless steel forgings for industrial valves
HG/T 20592 Steel pipe flanges (PN series)
HG/T 20615 Steel pipe flanges (Class series)
JB/T 6899 Fire test for valves
JB/T 7370 Flexible graphite braided packing
JB/T 7928 Industrial valves - Supply requirements
ISO 10497 Testing of valves - Fire type-testing requirements
3 Terms and Definitions
The following terms and definitions apply to this document.
3.1 Metal-seated Ball Valve
A ball valve with metal-to-metal sealing pair.
Note: The sealing pair refers to the valve seat sealing surface and the ball sealing surface.
4 Structural Types
Metal-seated ball valves (hereinafter referred to as "ball valves") are divided into floating ball valves and trunnion-mounted ball valves, with typical structures shown in Figures 1 to 3.
5 Technical Requirements
5.1 Pressure-Temperature Ratings
5.1.1 The pressure-temperature ratings of the ball valve body shall comply with the provisions of GB/T 12224.
5.1.2 The allowable pressure-temperature ratings of the ball valve are limited by the allowable working pressure, temperature, and pressure difference of the non-metallic sealing materials inside the valve. The allowable pressure-temperature ratings of the ball valve shall be determined by the smaller value between the pressure-temperature ratings of the non-metallic sealing material used and the pressure-temperature ratings of the ball valve body.
5.2 Face-to-Face and End-to-End Dimensions
The face-to-face and end-to-end dimensions of the ball valve shall comply with the provisions of GB/T 12221 or the requirements of the purchase order.
5.3 Connection Ends
5.3.1 Flanged connections shall comply with the provisions of GB/T 9124 (all parts) or HG/T 20592, HG/T 20615, or the requirements of the purchase order.
5.3.2 The surface roughness of the flange sealing connection faces shall comply with the provisions of GB/T 9124 (all parts) or the requirements of the purchase order.
5.3.3 Welded connections shall comply with the provisions of GB/T 12224 or the requirements of the purchase order.
5.3.4 The threads of internal threaded connections shall comply with the provisions of GB/T 7306 (all parts) and GB/T 12716, or the requirements of the purchase order.
5.4 Flow Passage of Ball Valves
The flow passages of full-bore and reduced-bore ball valves shall be circular, with the minimum diameters as specified in Table 1.
