Grade 12.9 Steel Housed (Pillow Block) Bearing are stocked to ISO / DIN. The grade provides requires plating or black-oxide protection and is magnetic; the practical service range is up to approx. +300 °C. Property data, grade comparison and the full size table follow.
Why Choose Grade 12.9 Steel for Housed (Pillow Block) Bearing — ISO / DIN (Series 120)
The highest common strength class, for high-load machine assembly. For housed (pillow block) bearing — iso / din (series 120), this matters when requires plating or black-oxide protection is the primary requirement.
Mechanical & Physical Properties
| Grade designation | class 12.9 |
|---|---|
| Magnetic response | Magnetic |
| Service temperature | up to approx. +300 °C |
| Corrosion characteristic | Requires plating or black-oxide protection |
Corrosion Behavior in Service
Carbon and alloy steel housed (pillow block) bearing — iso / din (series 120) 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 120) 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 120) Available in Grade 12.9 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 |