Standard: ASME B 18.21
Available sizes: 2.2 to 4 (6 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| 2.2 | 2.80 | 0.35 | 0.25 | 2.65 | 5.85 | 5.45 |
| 2.5 | 3.30 | 0.50 | 0.35 | 3.15 | 7.35 | 6.85 |
| 2.9 | 4.30 | 0.60 | 0.45 | 4.15 | 8.75 | 8.25 |
| 3 | 5.18 | 0.65 | 0.50 |
| 4.95 |
| 9.70 |
| 9.20 |
| 3.5 | 5.87 | 0.70 | 0.55 | 5.61 | 10.50 | 10.00 |
| 4 | 6.50 | 0.70 | 0.55 | 6.20 | 12.95 | 12.20 |
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.
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