Standard: GB 9074.25 - 1988
Available sizes: 2.5 to 5 (4 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 97.4(L) |
| DIN | DIN EN ISO 10673(L) |
| ISO | ISO 10673(L) |
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 2.5 | 2.83 | 0.8 | 0.9 | 2.73 | 9 | 0.33 | 8.64 | 0.7 |
| 3 | 4.75 | 1.2 | 1.4 | 4.57 | 15 | 1.41 | 14.57 | 1 |
| 4 | 7.64 | 2 | 2.2 | 7.42 | 24 |
Standard corrosion protection for indoor and mild outdoor environments.
Salt spray: 96–200 hours | RoHS compliant (trivalent chromium)
High-performance coating for automotive, marine, and harsh environments.
Salt spray: 720–1500 hours | Recommended for grade 8.8+
Heavy-duty protection for structural and outdoor applications.
Salt spray: 500–1000 hours | Thread tolerance adjustment required
Note for high-strength fasteners (Grade 10.9, 12.9): Electroplating processes require hydrogen embrittlement relief baking (minimum 4 hours at 200°C within 4 hours of plating). Contact our engineering team for grade-specific plating recommendations.
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.
| 6.08 |
| 23.48 |
| 1.8 |
| 5 | 11.53 | 3 | 3.3 | 11.26 | 37 | 21.99 | 36.38 | 2.7 |
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