Grade 8.8 Steel Spring (Roll) Pins pairs the standard ISO 8748 / DIN 1481 with a Grade 8.8 Steel base material. The sections below cover why engineers select this grade for spring (roll) pins, its corrosion and temperature behavior, and the sizes available.
Why Choose Grade 8.8 Steel for Spring (Roll) Pins
The workhorse medium-carbon alloy grade for structural joints. For spring (roll) 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 |
Corrosion Behavior in Service
Carbon and alloy steel spring (roll) pins require a coating for corrosion protection. Zinc plating (with or without passivation) is the most common; hot-dip galvanizing is used for outdoor structural service; black-oxide is mainly a tarnish-prevention finish for tool-room use.
Galvanic & Galling Considerations
For spring (roll) 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.
Sizes of Spring (Roll) Pins Available in Grade 8.8 Steel
| Nominal diameter (mm) | Recommended hole (mm) | Common length range (mm) | End chamfer (mm) | Material | Reference standard |
|---|---|---|---|---|---|
| 1.0 | 1.0 | 4~10 | 0.3 | Spring steel | ISO 8748 / DIN 1481 |
| 1.2 | 1.2 | 4~12 | 0.3 | Spring steel | ISO 8748 / DIN 1481 |
| 1.5 | 1.5 | 4~16 | 0.3 | Spring steel | ISO 8748 / DIN 1481 |
| 2.0 | 2.0 | 6~20 | 0.5 | Spring steel | ISO 8748 / DIN 1481 |
| 2.5 | 2.5 | 6~24 | 0.5 | Spring steel | ISO 8748 / DIN 1481 |
| 3.0 | 3.0 | 8~30 | 0.5 | Spring steel | ISO 8748 / DIN 1481 |
| 4.0 | 4.0 | 8~40 | 0.8 | Spring steel | ISO 8748 / DIN 1481 |
| 5.0 | 5.0 | 10~50 | 0.8 | Spring steel | ISO 8748 / DIN 1481 |
| 6.0 | 6.0 | 12~60 | 1.0 | Spring steel | ISO 8748 / DIN 1481 |
| 8.0 | 8.0 | 16~80 | 1.0 | Spring steel | ISO 8748 / DIN 1481 |
| 10.0 | 10.0 | 20~100 | 1.5 | Spring steel | ISO 8748 / DIN 1481 |
| 12.0 | 12.0 | 25~120 | 1.5 | Spring steel | ISO 8748 / DIN 1481 |
| 13.0 | 13.0 | 25~120 | 1.5 | Spring steel | ISO 8748 / DIN 1481 |
| 14.0 | 14.0 | 30~160 | 2.0 | Spring steel | ISO 8748 / DIN 1481 |
| 16.0 | 16.0 | 30~160 | 2.0 | Spring steel | ISO 8748 / DIN 1481 |
| 20.0 | 20.0 | 40~200 | 2.0 | Spring steel | ISO 8748 / DIN 1481 |