Needle Roller Bearing manufactured in Grade 12.9 Steel (class 12.9) 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 12.9 Steel for Needle Roller Bearing — ISO / DIN (Series 133)
The highest common strength class, for high-load machine assembly. For needle roller bearing — iso / din (series 133), 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 needle roller bearing — iso / din (series 133) 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 Needle Roller Bearing — ISO / DIN (Series 133), class 8.8 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 Needle Roller Bearing — ISO / DIN (Series 133) Available in Grade 12.9 Steel
| Bore d (mm) | Outer diameter D (mm) | Width B (mm) | Dynamic load C (kN) | Reference standard |
|---|---|---|---|---|
| 8 | 15 | 12 | 7.2 | ISO 1206 / GB/T 309 |
| 10 | 17 | 12 | 8.3 | ISO 1206 / GB/T 309 |
| 12 | 19 | 12 | 9.65 | ISO 1206 / GB/T 309 |
| 15 | 23 | 12 | 12.5 | ISO 1206 / GB/T 309 |
| 20 | 28 | 16 | 18.7 | ISO 1206 / GB/T 309 |
| 25 | 33 | 16 | 22.8 | ISO 1206 / GB/T 309 |
| 30 | 40 | 20 | 33.0 | ISO 1206 / GB/T 309 |
| 40 | 50 | 20 | 42.5 | ISO 1206 / GB/T 309 |