ANSI vs DIN vs GOST Flange Standards: A Comprehensive Comparison
Understanding Global Flange Standards
Flanges are manufactured to various international standards depending on region and application. This guide compares the three major standards: ANSI/ASME (American), DIN/EN (European), and GOST (Russian) to help you navigate global specifications.
ANSI/ASME Flange Standards
Primary Standards: ASME B16.5, ASME B16.47
Key Features:
- Pressure classes: 150, 300, 600, 900, 1500, 2500 lbs
- Sizes: 1/2″ to 60″ and larger
- Face types: RF, FF, RTJ, M/F, T/G
- Widely used in Americas, Middle East, Asia-Pacific
DIN/EN Flange Standards
Primary Standards: EN 1092-1, DIN 2501, DIN 2630-2638
Key Features:
- Pressure ratings: PN6, PN10, PN16, PN25, PN40, PN63, PN100
- Sizes: DN10 to DN4000
- Types: Type 01-37 covering various flange designs
- Standard in Europe and many international projects
GOST Flange Standards
Primary Standards: GOST 33259, GOST 28759, GOST 12820-12822
Key Features:
- Pressure ratings: 0.1 to 20.0 MPa
- Sizes: DN10 to DN2400
- Common in Russia, CIS countries, and related projects
- Material designations use Russian standards (e.g., 12Х18Н10Т)
Key Differences Comparison
| Aspect | ANSI/ASME | DIN/EN | GOST |
|---|---|---|---|
| Pressure System | Class (lbs) | PN (bar) | MPa |
| Size System | NPS (inches) | DN (mm) | DN (mm) |
| Bolt Pattern | Imperial | Metric | Metric |
| Dimensions | Different | Different | Different |
Interchangeability Considerations
Important: Flanges from different standards are generally NOT interchangeable due to differences in:
- Outside diameter
- Bolt circle diameter
- Bolt hole size and quantity
- Flange thickness
- Raised face dimensions
Material Equivalents
- Carbon Steel: ASTM A105 ≈ P235GH ≈ 20
- 304 Stainless: ASTM A182 F304 ≈ X5CrNi18-10 ≈ 08Х18Н10
- 316 Stainless: ASTM A182 F316 ≈ X5CrNiMo17-12-2 ≈ 10Х17Н13М2Т
Selecting the Right Standard
Choose based on:
- Project location and regional requirements
- Existing piping system standards
- Client specifications
- Equipment connection requirements
- Regulatory compliance needs
Conclusion
Understanding the differences between ANSI, DIN, and GOST flange standards is essential for global projects. Always verify compatibility and never mix standards without proper adaptation. When in doubt, consult with qualified engineers and refer to applicable codes.

