Standard for quality grade of deep groove ball bearing

Deep groove ball bearings, different grades of bearings, prices vary greatly. There are three standards to evaluate the quality of deep groove ball bearings
1. Bearing tolerance: tolerance and form and position tolerance of deep groove ball bearing are expressed by tolerance grade. For example, P6 grade is better than P0 grade, P5 grade is better than P6 grade, and the price of P5 is twice that of P6 grade
2. Vibration grade: Z0, Z1, Z2, Z4, etc. Group Z1 was better than group Z0, group Z2 was better than group Z1, or group V1 was better than group V0, group V2 was better than group v1
3. There is no standard for noise. But for some special equipment, there are special requirements for noise
4. Bearing material: deep groove ball bearing material is divided into bearing steel, carbon steel, stainless steel, ceramics, bearing prices vary greatly.