Are bearings standard?

Are bearings standard? First of all, we need to know how to define standard parts. The official explanation for standard parts is as follows: standard parts refer to the structure, size, drawing, marking and other aspects have been completely standardized, and commonly used zero (part) parts produced by professional factories, such as threaded parts, keys, pins, rolling bearings and so on. In a broad sense, it includes standardized fasteners, connectors, transmission parts, seals, hydraulic components, pneumatic components, bearings, springs and other mechanical parts.

It describes that "the structure, size, drawing, marking and other aspects of the standard parts are completely standardized." Refers to the same type of bearing, the same size structure, with installation interchangeability. For example, the 608 bearing, its dimensions are inner diameter 8mmx outer diameter 22mmx width 7mm, buy any brand of 608 bearing, its dimensions are the same. In this sense, we say that the bearing is a standard part, which only refers to the same size.

However, for the 608 bearing, the external size is the same, the interior may not be the same. What can really ensure the long-term normal operation of bearings is the internal structural parameters.

The same 608 bearing can be very different inside. For example, the clearance can be MC1, MC2, MC3, MC4, MC5 according to the fit tolerance selection; Cages can be made of iron or plastic; The precision can be P0, P6, P5, P4, etc., selected according to the purpose; The oil can be selected from high temperature to low temperature according to the working conditions, and the amount of oil sealing is also different.

In this sense, we also say that the bearing is not a standard part. According to the specific working conditions, 608 bearings with different performance can be provided for you to choose. If it is to be standardized, the various parameters of the bearing must be limited. For bearings, you must not simply regard them as standard parts, and you must understand the meaning of non-standard parts.