Standard: CNS 3128 - 1998
Available sizes: (M3.5) to M6 (8 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 | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M3.5) | 1.5 | 5.6 | 6.4 | 10.8 | 14.6 | 0.6 | 0.15 | 8.4 | 8.04 | 10 | 17.77 |
| M1.6 | 0.4 | 1 | 1.1 | 2.3 | 3.1 | 0.2 | 0.1 | 1.6 |
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.
| 1.35 |
| 2 |
| 4.32 |
| M2 | 0.5 | 1.5 | 1.7 | 3.45 | 4.6 | 0.4 | 0.15 | 2.4 | 2.15 | 3 | 6.01 |
| M2.5 | 0.7 | 2 | 2.3 | 4.6 | 5.9 | 0.4 | 0.15 | 3.2 | 2.9 | 4 | 7.66 |
| M3 | 1 | 3.4 | 3.9 | 6.75 | 8.9 | 0.5 | 0.15 | 5.2 | 4.9 | 6 | 11.05 |
| M4 | 2 | / | 10.7 | 15.1 | 19.6 | 0.6 | / | 14.1 | 13.4 | 14 | 23.35 |
| M5 | 2.5 | 10.6 | 12.1 | 19.5 | 24.9 | 0.8 | 0.2 | 15.8 | 15.1 | 18 | 29.56 |
| M6 | 2.5 | 11.8 | 13.5 | 21.6 | 27.7 | 0.8 | 0.2 | 18 | 16.9 | 20 | 32.95 |
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