27/07/2018
Technical requirements for wheel bearings
1. Materials and heat treatment
Ferrule
1 without fl**ges. Bearing steel GCR15, integral quenching, MRC (hardness) 58-62.
2 with fl**ges. 55, 65MN, etc., surface quenching, MRC (hardness) 58-64.
Rolling body
1 ball. Bearing steel GCR15 is integrally quenched, MRC 58-64.
2 rollers. Ibid.
Cage
1 engineering plastics: nylon + 25% glass fiber, lighter, less centrifugal force.
2 metal: steel, copper, aluminum, alloy, heavier, centrifugal force is larger.
Seal ring
1 single lip. Friction, waterproof and dustproof.
2 lips. Friction, waterproof and dustproof.
3 card type. Friction, waterproof and dustproof.
Three ways of sealing, increasing in an incremental manner
2. Tolerance
Without fl**ges. Similar to ordinary bearing 0
With fl**ges. Spline, fl**ge
3. Surface roughness
Same as 0-level bearing, with surface Ra 2.5Ξm
4. Clearance
1 radial clearance. Matching time of inner and outer ring: Calculate Îą (contact angle), R (two channel distance), DN (steel ball), etc.
2 axial clearance. When using, the national standard is 0.07-0.1mm or according to customer requirements.
5. Residual magnetism
6. Vibration
1 speed (standard), speed, high, medium and low wave (classified without standard, roughly three bands), standard ZV1~ZV4
2 acceleration, speed, high school low wave, standard Z1~Z4
7. Appearance quality
Crack, rust, bruise, black skin
8. Life expectancy
1 simulation experiment. In-plant testing machine (acceleration)
2 endurance test. In-plant field (cold, hot, wet, dry)
