Standard: JB /T 7919.3 - 1999
Available sizes: Tr220 to Tr360 (8 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| Tr220 | HML48 | MSL48 | 290 | 34 | 4 | 240 | 9 | 270 | 270 | 20 |
| Tr240 | HML56 | MSL56 | 330 | 38 | 4 | 280 | 10 | 310 | 310 | 24 |
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.
| Tr260 | HML64 | MSL64 | 380 | 42 | 5 | 320 | 12 | 356 | 356 | 24 |
| Tr280 | HML72 | MSL72 | 420 | 45 | 5 | 360 | 13 | 394 | 394 | 28 |
| Tr300 | HML80 | MSL76 | 470 | 52 | 5 | 400 | 14 | 442 | 442 | 28 |
| Tr320 | HML88 | MSL88 | 520 | 60 | 5 | 440 | 15 | 490 | 490 | 32 |
| Tr340 | HML96 | MSL96 | 560 | 60 | 5 | 480 | 15 | 530 | 530 | 36 |
| Tr360 | HML500 | MSL96 | 580 | 68 | 5 | 500 | 15 | 550 | 550 | 36 |
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