Standard: UNI 6753
Available sizes: 2 to 7 (7 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 5356 |
| DIN | DIN ISO 2936 |
| ISO | ISO 2936 |
| UNI | UNI 6753 |
| ANSI | ANSI/ASME B 18.3.2M |
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| 2 | 2.5 | 18 | 17 | 2.46 | 56 | 53 |
| 2.5 | 4 | 25 | 23 | 3.96 | 70 | 66 |
| 3 | 6 | 32 | 30 | 5.96 | 90 | 86 |
| 4 | 8 | 38 | 36 | 7.94 | 100 |
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.
| 95 |
| 5 | 10 | 40 | 38 | 9.94 | 112 | 106 |
| 6 | 14 | 56 | 53 | 13.89 | 140 | 133 |
| 7 | 19 | 70 | 67 | 18.87 | 180 | 171 |
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