Standard: QC /T 356 - 1999
Available sizes: M25 to M30 (3 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| M25 | 1.5 | 24 | 38 | 41 | 40.38 | 24.42 | 45.63 |
| M27 | 1.5 | 22 | — | 36 | 35.38 | 22.42 | 39.95 |
| M30 | 1.5 | 26(22) | 38 | 41(38) | 40.38(37.38) | 26.42(22.42) | 45.63(42.24) |
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.
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