For housed (pillow block) bearing in Grade 8.8 Steel, the controlling selection factors are corrosion exposure, strength requirement and service temperature. The grade data for Grade 8.8 Steel (class 8.8) is summarized below together with every size supplied.
Why Choose Grade 8.8 Steel for Housed (Pillow Block) Bearing — ISO / DIN (Series 122)
The workhorse medium-carbon alloy grade for structural joints. For housed (pillow block) bearing — iso / din (series 122), 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 housed (pillow block) bearing — iso / din (series 122) 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 housed (pillow block) bearing — iso / din (series 122) 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 Housed (Pillow Block) Bearing — ISO / DIN (Series 122) Available in Grade 8.8 Steel
| Shaft size (mm) | Housing length (mm) | Total height (mm) | Bolt center distance (mm) | Bolt size | Reference standard |
|---|---|---|---|---|---|
| 15 | 90 | 38 | 65 | M10 | ISO 113 / GB/T 7813 |
| 20 | 108 | 42 | 75 | M10 | ISO 113 / GB/T 7813 |
| 25 | 127 | 47 | 90 | M12 | ISO 113 / GB/T 7813 |
| 30 | 140 | 55 | 100 | M12 | ISO 113 / GB/T 7813 |
| 35 | 162 | 62 | 115 | M14 | ISO 113 / GB/T 7813 |
| 40 | 175 | 68 | 130 | M14 | ISO 113 / GB/T 7813 |
| 50 | 205 | 75 | 150 | M16 | ISO 113 / GB/T 7813 |
| 60 | 250 | 85 | 180 | M16 | ISO 113 / GB/T 7813 |
| 80 | 300 | 105 | 220 | M20 | ISO 113 / GB/T 7813 |