Standard: GB 6170 - 1986
Available sizes: M1.6 to M6 (7 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 6170 |
| IS | IS 1364(-3) |
| DIN | DIN EN ISO 4032 |
| ISO | ISO 4032 |
| UNI | UNI 5588 |
| ANSI | ASME/ANSI B 18.2.4.1M |
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| M1.6 | 0.4 | 3.82 | 4.32 | 1.6 | 1.35 | 4 |
| M2 | 0.5 | 5.32 | 6.01 | 2.4 | 2.15 | 5.5 |
| M2.5 | 0.8 | 7.78 | 8.79 | 4.7 | 4.4 | 8 |
| M3 | 1.25 | 12.73 | 14.38 | 6.8 |
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.
| 6.44 |
| 13 |
| M4 | 1.75 | 17.73 | 20.03 | 10.8 | 10.37 | 18 |
| M5 | 2 | 23.67 | 26.75 | 14.8 | 14.1 | 24 |
| M6 | 2.5 | 29.16 | 32.95 | 18 | 16.9 | 30 |
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