Standard: GB 845 - 1976
Available sizes: 2.5 to 4 (3 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 845 |
| NF | NF E 25-658 |
| DIN | DIN EN ISO 7049 |
| ISO | ISO 7049 |
| UNI | UNI 6954 |
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| 2.5 | 5.5 |
| 1.58 |
| 0.2 |
| 5.2 |
| 1.8 |
| 1.8 |
| 2.4 |
| 1.92 |
| 1.8 |
| 3 | 8.20 | 2.8 | 0.4 | 7.84 | 3 | 3 | 4 | 3.2 | 3 |
| 4 | 10.50 | 3.4 | 0.4 | 10.07 | 3.6 | 3.6 | 4.8 | 3.8 | 3.6 |
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.
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