Standard: GB /T 158 - 1996
Available sizes: 10 to 8 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 10 | M20 | 28.42 | 28 | 34.5 | 33.5 | 21.7 | 21.4 | 14.35 | 13.65 | 34 | 14 |
| 12 | M30 | 44.5 | 44 | 53.6 | 52.4 | 35.6 | 35.3 |
| 23.42 |
| 22.58 |
| 53 |
| 23 |
| 14 | M42 | 60.6 | 60 | 75.6 | 74.4 | 47.6 | 47.3 | 32.5 | 31.5 | 75 | 32 |
| 18 | M48 | 70.6 | 70 | 85.7 | 84.3 | 53.6 | 53.3 | 36.5 | 35.5 | 85 | 36 |
| 5 | M5 | 8.29 | 8 | 10.29 | 9.71 | 5.7 | 5.5 | 4.24 | 3.76 | 10 | 4 |
| 6 | M8 | 12.35 | 12 | 15.35 | 14.65 | 9.7 | 9.5 | 6.24 | 5.76 | 15 | 6 |
| 8 | M12 | 16.35 | 16 | 22.42 | 21.58 | 13.7 | 13.4 | 8.29 | 7.71 | 22 | 8 |
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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