Standard: GB /T 97.4
Available sizes: 2 to 4 (5 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 | 2.25 | 0.6 | 0.65 | 2.35 | 8 | 0.218 | 7.64 | 0.55 |
| 2.5 | 3.2 | 0.8 | 0.85 | 3.32 | 11 | 0.546 | 10.57 | 0.75 |
| 3 | 4.55 | 1 | 1.06 | 4.67 | 15 |
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.
| 1.26 |
| 14.57 |
| 0.94 |
| 3.5 | 7.4 | 2 | 2.09 | 7.55 | 24 | 6.43 | 23.48 | 1.91 |
| 4 | 11 | 3 | 3.11 | 11.27 | 37 | 23.08 | 36.38 | 2.89 |
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