Standard: TB /T 845 - 1991
Available sizes: R 1/2 to R 3/8 (5 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| R 1/2 | 40 | 0.237 | 24 | 1.5 | 27 | 25.7 | 16 | 16 | 35 | 32 |
| R 1/4 | 25 | 0.041 | 17 | 1.5 | 14 | 13 | — | — | 18 | — |
| R 1/8 | 20 | 0.014 |
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.
| 14 |
| 1 |
| 10 |
| 9.1 |
| — |
| — |
| 13 |
| — |
| R 3/4 | 46 | 0.743 | 30 | 1.5 | 36 | 34.4 | 20 | 18 | 48 | 52 |
| R 3/8 | 33 | 0.109 | 20 | 1.5 | 19 | 17.7 | 12 | — | 24 | 20 |
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