Standard: GB 879 - 1986
Available sizes: 1 to 6 (8 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 879.1 |
| DIN | DIN EN ISO 8752 |
| ISO | ISO 8752 |
| UNI | UNI 6873 |
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| 1 | 1.7 | 20° | 1.58 | 1.8 | 0.3 | 0.3 | 1 |
| 1.5 | 2.7 | 20° | 4.38 | 2.8 | 0.5 | 0.5 | 1 |
| 2 | 4.3 | 20° | 11.24 | 4.5 | 0.8 | 0.8 | 1.6 |
| 2.5 |
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.
| 6.3 |
| 20° |
| 26.04 |
| 6.6 |
| 1 |
| 1 |
| 2 |
| 3 | 10.3 | 15° | 70.16 | 10.6 | 2 | 2 | 2 |
| 4 | 16.4 | 15° | 171 | 16.7 | 3 | 3 | 2.4 |
| 5 | 25.4 | 15° | 438.5 | 25.8 | 4.5 | 3 | 3.5 |
| 6 | 30.4 | 15° | 631.4 | 30.8 | 5 | 3 | 3.5 |
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