Stainless flange standards: GB/T 9119, ASME B16.5 and EN 1092-1
Chinese, US and European flange standards differ in pressure class, sealing face and dimensions. Cross-reference pressure class, face type and bolt hole spacing together.
Stainless flange purchasing commonly involves GB/T 9119, ASME B16.5 and EN 1092-1. Key comparison points:
| Item | GB/T 9119 | ASME B16.5 | EN 1092-1 |
|---|---|---|---|
| Pressure class | PN series | Class 150/300/600… | PN 6/10/16/25/40… |
| Sealing face | RF/FM/M etc. | RF/RJ/FF | Type A/B/C/D… |
| Dimensions/bolts | by nominal size | inch bolt spacing | metric and inch |
| Material | Chinese grades | ASTM A182 forgings etc. | EN 10222-5 etc. |
Purchasing advice:
1) Do not mix the three systems in one project unless pressure class, face type and bolt holes are confirmed interchangeable.
2) Cross-reference tables indicate approximate pressure classes only; actual dimensions must follow the standard dimension tables.
3) Match sealing face type (RF/FF/RJ) with the gasket, or leakage is likely.
4) For export projects, state the standard edition and material grade system (e.g. ASME B16.5 + ASTM A182 F316L).
Flanges are pressure-retaining components — writing the standard and material clearly matters far more than the word “stainless”.
