GB /T 6172.2 (GB) and NF E 25-412 (NF) are equivalent fastener standards that specify the same or very similar products. Both standards cover 7 fastener types in our database.
GB /T 6172.2 (GB standard) and NF E 25-412 (NF standard) are equivalent standards that define the same fastener geometry and mechanical requirements. Minor differences may exist in tolerances, marking requirements, or referenced test methods, but the products are interchangeable in most applications. Always verify specific project requirements with your engineer.
| Property | GB /T 6172.2 | NF E 25-412 |
|---|---|---|
| Standard Body | GB | NF |
| Product Types | 7 fastener types | |
| Interchangeable? | Yes — equivalent standard | |
From: Prevailing Torque-Type Hexagon Lock Nuts with Polyamide Ring-ISO Metric Coarse and Fine Thread - Product Grade A — applies to both GB /T 6172.2 and NF E 25-412
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| (M7) | 2 | 22 | 19.6 | 1.5 | 14 | 7 | 19.3 |
| M4 | 0.8 | 8 | 1.13 | / | 5.4 | 2.5 | / |
| M5 | 1 | 11 | 2.64 |
Both GB /T 6172.2 and NF E 25-412 fasteners are available with various surface treatments. Common options for these standards include:
Request detailed technical specifications, material certifications, and availability information for your application requirements. Our engineering team can provide product recommendations, custom specifications, and technical documentation.
| ✓ |
| Prevailing Torque Type Hexagon Thin Nuts (with non-metallic insert) | ✓ |
| / |
| 7 |
| 3.5 |
| / |
| M6 | 1.5 | 17 | 9.48 | 1.25 | 10 | 5 | 9.36 |
| M8 | 2 | 24 | 25.5 | 1.5 | 15 | 8 | 25 |
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