Standard: SZJGJ 001
Available sizes: ST2.2 to ST4.2 (7 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 845 |
| NF | NF E 25-658 |
| DIN | DIN EN ISO 7049 |
| ISO | ISO 7049 |
| UNI | UNI 6954 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|
| ST2.2 | 1.1 | 0.86 | 1.43 | 1.7 | 1.2 | 5.4 | 5.1 | 2 | 3.5 | 1.9 | 0.1 |
| ST2.9 | 1.3 | 1.4 | 2.03 | 2.1 | 1.4 | 6.8 | 6.5 | 2 | 4.2 | 2.3 | 0.1 |
| ST3 | 1.34 | 1.63 | 2.26 | 2.2 | 1.5 | 7.3 | 7 | 2 | 4.4 | 2.4 | 0.2 |
| ST3.5 | 1.6 | 2.26 | 2.87 | 2.9 | 2 | 9.1 | 8.7 | 2 | 5 | 3.1 | 0.2 |
| ST3.9 | 1.8 | 2.49 | 3.15 | 3.3 | 2.2 | 10.7 | 10.3 | 3 | 6.5 | 3.5 | 0.25 |
| ST4.0 | 1.8 | 3 | 3.66 | 3.9 | 2.4 | 12.4 | 11.8 | 3 | 7.1 | 4.1 | 0.25 |
| ST4.2 | 2.1 | 3.73 | 4.36 | 4.5 | 2.4 | 13.3 | 13 | 3 | 7.8 | 4.8 | 0.25 |
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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