Standard: JB /T 7934 - 1999
Available sizes: 20 to 40 (8 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| 20 | 26 | 0.005 | 0.01 | 6.3 | 5.3 | 4.5 |
| 22 | 32 | 0.08 | 0.01 | 6.3 | 5.3 | 5.6 |
| 25 | 36 | 0.1 | 0.01 | 6.3 | 5.3 | 6.4 |
| 28 | 45 | 0.2 | 0 02 | 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.
| 6.6 |
| 9.9 |
| 30 | 57 | 0.4 | 0.05 | 10 | 8.6 | 16.2 |
| 32 | 68 | 0.7 | 0.07 | 12 | 10.4 | 23.5 |
| 35 | 79 | 1.12 | 0.11 | 14 | 12.2 | 32 |
| 40 | 91 | 1.81 | 0.19 | 17 | 15 | 45 |
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