For Angular Contact Ball Bearing — ISO / DIN (Series 137) in Grade 8.8 Steel, the controlling decisions are corrosion, strength and service temperature. This guide summarizes those three for Grade 8.8 Steel Angular Contact Ball Bearing — ISO / DIN (Series 137) and lists every size we supply.
Why Choose Grade 8.8 Steel for Angular Contact Ball Bearing — ISO / DIN (Series 137)
The workhorse medium-carbon alloy grade for structural joints. For angular contact ball bearing — iso / din (series 137), 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 angular contact ball bearing — iso / din (series 137) 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.
Comparable Grades
For Angular Contact Ball Bearing — ISO / DIN (Series 137), 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 Angular Contact Ball Bearing — ISO / DIN (Series 137) Available in Grade 8.8 Steel
| Bore d (mm) | Outer diameter D (mm) | Width B (mm) | Contact angle (deg) | Dynamic load C (kN) | Reference standard |
|---|---|---|---|---|---|
| 10 | 30 | 9 | 15 | 5.85 | ISO 76 / GB/T 292 |
| 15 | 35 | 11 | 15 | 8.06 | ISO 76 / GB/T 292 |
| 20 | 47 | 14 | 15 | 12.5 | ISO 76 / GB/T 292 |
| 25 | 52 | 15 | 15 | 14.8 | ISO 76 / GB/T 292 |
| 30 | 62 | 16 | 15 | 20.3 | ISO 76 / GB/T 292 |
| 40 | 80 | 18 | 15 | 32.5 | ISO 76 / GB/T 292 |
| 50 | 90 | 20 | 15 | 37.5 | ISO 76 / GB/T 292 |
| 60 | 110 | 22 | 25 | 55.0 | ISO 76 / GB/T 292 |
| 70 | 125 | 24 | 25 | 70.2 | ISO 76 / GB/T 292 |
| 80 | 140 | 26 | 25 | 82.4 | ISO 76 / GB/T 292 |