# What Is The Static Load Rating And Dynamic Load Rating Of A Bearing?

Bearing load is defined as the force that’s transferred from one bearing ring.

Usually when we check the bearing type, we often see Cr and Cor two options, what do these two groups of letters represent? Now tell you, Cr refers to the dynamic load rating of the bearing, Cor refers to the static load rating of the bearing. So what is the static load rating and dynamic load rating of a bearing? What is the relationship and difference between these two?

In the design of rolling bearings in often used in the three basic parameters are: to meet a certain fatigue life requirements of the basic dynamic load rating Cr (radial) or Ca (axial); to meet a certain static strength requirements of the basic static strength rating Cor (radial) or Coa (axial) and control the bearing wear limit speed No.

##### Why is the dynamic load rating of the bearing greater than the static load rating?

The rated dynamic load is the load that the bearing is subjected to at a rated life of 1 million revolutions. The rated static load refers to the bearing under the load, static when the load is the largest rolling body and collar raceway contact, rolling body and collar raceway of the permanent deformation of the sum of rolling body diameter of one million.

Bearing life and bearing load rating has a certain relationship, then what situation we through the bearing load rating to choose the bearing? The main points are as follows.

##### Note: In some cases, the size of the bearing should be selected by the rated static load, rather than calculating the bearing life.

1, under the action of continuous or intermittent shock loads, the bearing is stationary.

2, in the role of the load, bearing only slow reciprocating oscillation or regulatory movement.

3, in the role of the load, bearing speed is very low (less than 10 revolutions per minute flat) and only a very short life. In particular, in this case, for a given equivalent load P, the life formula will give a very low required basic dynamic load rating C. Therefore, the selected bearing may be severely overloaded in actual operation.

4、In addition to the normal working load required, the bearing is also subjected to very heavy shock loads and the bearing is rotating.

The above various cases, the bearing can withstand the load does not depend on the fatigue of the material, but according to the load on the raceway caused by the degree of permanent deformation.

##### Welcome to contact me to get the price of bearings！

-Email:wanyu@sdwybearing.com