Crossed roller bearings during operation load causes injury card processing

The so-called injury card is wound the sliding surface of the bearing part generated summary slight burn surface damage arising. Slide surface, rolling surface circumferential direction of the linear scars. roller bearing linear scar near the end of the pendulum roller end surface of the card collar injury.
Bearing injury phenomenon occurs card:
Excessive load, excessive preload. Poor lubrication. Foreign objects. Tilt inner outer, shaft deflection. Shaft, bearing housing poor accuracy.
Bearing injury phenomenon occurs when the card measures:
     Check the size of the load. Preload should be appropriate. Improved lubricants and lubrication methods. Check shaft, bearing housing precision.
Select the load vector with the first consideration should be the case relative to the rotation of the ferrule. In accordance with the synthetic radial load vector relative to the rotating ring case, composite ferrule exposure can be divided into: a fixed load, rotational load and oscillating load.
a. fixed load
Role in the synthesis of radial load on the ring by ring raceway of the local area is exposed, and transmitted to the shaft or bearing the appropriate local area, this load is called a fixed load. Its characteristics are synthetic radial load vector with ferrule relatively static. Directed to bear the load of the ring can be used looser fit.
b. rotational load
Acting on the radial load on the composite ring, the raceway along the circumferential direction of rotation, sequentially from the various parts of the exposure, this load called rotational load, the radial load characteristics of the synthesis vector with respect to the rotating ring. Withstand the rotational load of the ring tight fit to be elected, in exceptional circumstances, such as the load is very light, or under heavy load low speed only occasionally rings, bearings use hard materials and surface roughness is higher, rotating load to bear Rings can also be used looser fit.
c. swing load
Synthesis of acting on the ferrule fixed radial load direction, this load is called swing load or non-directional load, which is characterized by the synthesis of the ferrule effect radial load vectors ring raceway to swing within a certain area, certain areas of the roller is exposed, or the load acting on the bearing is an impact load, the vibration load, the direction of the load values ​​change frequently. Have to bear the load swing bearing, outer ferrule with the state, with the housing bore should be a tight fit.
Bearing inner diameter and outer diameter tolerances are manufactured in accordance with the standard, the bearing inner ring and the shaft, the outer ring and housing bore with the tightness of the journal can only be controlled housing bore tolerances and tolerances to be achieved. Cross roller bearing inner ring and the shaft hole basis with the use of the bearing outer ring and housing bore with the introduction of machine axis system. Rolling with commonly used. With the correct choice, you must know the actual load bearing conditions, temperature and other requirements, and in fact it is very difficult. Therefore, in most cases is selected according refinements fit.