ANSI/ASME B 18.3.1M (ANSI) and ISO 12474 (ISO) are equivalent fastener standards that specify the same or very similar products. Both standards cover 1 fastener type in our database.
ANSI/ASME B 18.3.1M (ANSI standard) and ISO 12474 (ISO 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 | ANSI/ASME B 18.3.1M | ISO 12474 |
|---|---|---|
| Standard Body | ANSI | ISO |
| Product Types | 1 fastener type | |
| Interchangeable? | Yes — equivalent standard | |
| Product | Has Specs |
|---|---|
| Hexagon Socket Head Cap Screws | ✓ |
From: Hexagon Socket Head Cap Screws — applies to both ANSI/ASME B 18.3.1M and ISO 12474
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M1.6 | 0.4 | 1.5 | 1.86 | 2.6 | 2 | 3.8 | 3.98 | 1.733 | 2.00 | 3.62 | 1.86 |
| M2 | 0.5 | 2.5 | 2.86 | 3.6 |
Both ANSI/ASME B 18.3.1M and ISO 12474 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.
| 3 |
| 5.5 |
| 5.68 |
| 2.873 |
| 3.00 |
| 5.32 |
| 2.86 |
| M2.5 | 0.8 | 4 | 4.82 | 5.7 | 5 | 8.5 | 8.72 | 4.583 | 5.00 | 8.28 | 4.82 |
| M3 | 1.25 | 6 | 7.64 | 9.2 | 8 | 13 | 13.27 | 6.683 | 8.00 | 12.73 | 7.78 |
| M4 | 1.75 | 10 | 11.57 | 13.7 | 12 | 18 | 18.27 | 11.429 | 12.00 | 17.73 | 11.73 |
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