Standard: JB /T 7934 - 1999
Available sizes: 12 to 20 (5 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 12 | 37 | 0.08 | M5×8 | 1 | 12 | 9 | 0.052 | 5 | 11 | 9 |
| 14 | 44 | 0.12 | M5×12 | 1.5 | 15 | 12 | 0.08 | 5 | 15 | 10 |
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.
| 16 | 47 | 0.15 | M5×12 | 1.5 | 17 | 12 | 0.14 | 5 | 15 | 16 |
| 18 | 50 | 0.2 | M5×12 | 2 | 22 | 14 | 0.28 | 5 | 18 | 25 |
| 20 | 72 | 0.4 | M6×16 | 2 | 28 | 18 | 0.55 | 12 | 22 | 37 |
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