Deep Groove Ball Bearing manufactured in Grade 8.8 Steel (class 8.8) are dimensioned to ISO / DIN. The sections below give the mechanical and physical properties of the grade, its behavior in corrosive and elevated-temperature service, and the full size table.
Why Choose Grade 8.8 Steel for Deep Groove Ball Bearing — ISO / DIN (Series 118)
The workhorse medium-carbon alloy grade for structural joints. For deep groove ball bearing — iso / din (series 118), 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 deep groove ball bearing — iso / din (series 118) 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 Deep Groove Ball Bearing — ISO / DIN (Series 118), 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 Deep Groove Ball Bearing — ISO / DIN (Series 118) Available in Grade 8.8 Steel
| Bore d (mm) | Outer diameter D (mm) | Width B (mm) | Dynamic load C (kN) | Limit speed (rpm) | Reference standard |
|---|---|---|---|---|---|
| 10 | 30 | 9 | 5.1 | 32000 | ISO 15 / GB/T 276 |
| 12 | 32 | 10 | 6.95 | 28000 | ISO 15 / GB/T 276 |
| 15 | 35 | 11 | 7.65 | 24000 | ISO 15 / GB/T 276 |
| 17 | 40 | 12 | 9.56 | 22000 | ISO 15 / GB/T 276 |
| 20 | 47 | 14 | 12.7 | 18000 | ISO 15 / GB/T 276 |
| 25 | 52 | 15 | 14.0 | 16000 | ISO 15 / GB/T 276 |
| 30 | 62 | 16 | 19.5 | 13000 | ISO 15 / GB/T 276 |
| 35 | 72 | 17 | 25.5 | 11000 | ISO 15 / GB/T 276 |
| 40 | 80 | 18 | 30.7 | 10000 | ISO 15 / GB/T 276 |
| 45 | 85 | 19 | 33.2 | 9500 | ISO 15 / GB/T 276 |
| 50 | 90 | 20 | 35.1 | 9000 | ISO 15 / GB/T 276 |
| 60 | 110 | 22 | 52.7 | 7500 | ISO 15 / GB/T 276 |