Standard: JB /T 7919.3 - 1999
Available sizes: Tr220 to Tr300 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Tr220 | HM48 | MS44 | MB48 | 300 | 34 | 4 | 240 | 10 | 280 | 270 | 20 |
| Tr240 | HM56 | MS52 | MB56 | 350 | 38 | 4 | 280 | 12 |
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.
| 326 |
| 320 |
| 24 |
| Tr260 | HM64 | MS64 | / | 400 | 42 | 5 | 320 | 12 | 376 | 360 | 24 |
| Tr280 | HM72 | MS68 | / | 460 | 58 | 5 | 360 | 15 | 430 | 420 | 28 |
| Tr300 | HM76 | MS76 | / | 490 | 60 | 5 | 380 | 18 | 454 | 440 | 32 |
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