Grade 8.8 Steel Split Cotter Pins combine the dimensional form of ISO 1234 / DIN 94 with the material properties of grade class 8.8: requires plating (zinc) for corrosion protection, magnetic, service range up to approx. +300 °C. This page summarizes the grade data, its corrosion behavior in service, the comparable grades, and the sizes supplied.
Why Choose Grade 8.8 Steel for Split Cotter Pins
The workhorse medium-carbon alloy grade for structural joints. For split cotter pins, this matters when requires plating (zinc) for corrosion protection is the primary requirement.
Mechanical & Physical Properties
| Grade designation | class 8.8 |
|---|---|
| Magnetic response | Magnetic |
| Service temperature | up to approx. +300 °C |
| Corrosion characteristic | Requires plating (zinc) for corrosion protection |
Galvanic & Galling Considerations
For split cotter pins in steel, the dominant compatibility issue is hydrogen embrittlement at high property classes (10.9 and above) when electroplated. Plating must be followed by an appropriate baking treatment, or a non-electroplated finish (mechanical zinc, zinc flake) should be substituted.
Comparable Grades
For Split Cotter Pins, class 10.9 or 12.9 is the comparable strength step. Move up when the joint preload approaches the proof load of the current class; move down when the joint is over-specified. For corrosion-critical service, switch to stainless A2 or A4.
Sizes of Split Cotter Pins Available in Grade 8.8 Steel
| Nominal diameter (mm) | Hole dia min (mm) | Hole dia max (mm) | Common length range (mm) | Material | Reference standard |
|---|---|---|---|---|---|
| 0.6 | 0.7 | 0.9 | 6~16 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 0.8 | 0.9 | 1.1 | 6~20 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 1.0 | 1.1 | 1.3 | 8~25 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 1.2 | 1.3 | 1.5 | 8~30 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 1.6 | 1.7 | 1.9 | 10~40 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 2.0 | 2.1 | 2.4 | 12~50 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 2.5 | 2.7 | 3.0 | 14~63 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 3.2 | 3.4 | 3.8 | 18~80 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 4.0 | 4.3 | 4.8 | 22~100 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 5.0 | 5.4 | 5.9 | 25~125 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 6.3 | 6.7 | 7.4 | 32~160 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 8.0 | 8.5 | 9.3 | 40~200 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 10.0 | 10.6 | 11.5 | 50~250 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |
| 13.0 | 13.8 | 14.9 | 63~315 | Low-carbon steel / stainless | ISO 1234 / DIN 94 |