How to judge the quality of bearings by appearance

Bearings are not only widely used in various mechanical equipment, but also have a great effect on the wheels of vehicles. The key is to make them run normally. So how to distinguish the quality of bearings from their appearance? The following aspects are several aspects that must be paid attention to in the appearance inspection:

(1) Various cracks, such as raw material cracks, forging cracks, heat treatment process cracks and cutting cracks, etc., such cracks will become stress sources and expand rapidly during the entire operation of the bearing, resulting in the cracking of the bearing. , the service life of the bearing and the safety factor in work are greatly harmful. How to distinguish the quality of bearings according to their appearance

(2) All kinds of mechanical equipment scars, such as abrasion, scratches, squeezing, knocking, etc., will lead to poor bearing installation, resulting in wheel weight and stress, resulting in reduced rotation accuracy and service life.

(3) Corrosion, black skin and black spots, the latter two are the shortcomings of very easy storage of water and waste, and are most likely to develop into rust. Corrosion, on the other hand, is a contaminant that causes poor installation, initial damage, and exhaustion, and more severe rust can damage bearings.

(4) peeling and stretching, the two shortcomings are not stable with the base metal material, and there is usually a carburized or carbon-depleted condition around it at different levels, and the raw material is very easy to collapse, dent or wear. It is very bad for bearing service life and accuracy.

(5) For the quality of riveting or electric welding of ball bearings, the key point is to check whether the bolt head is deviated, inclined, loose, lack of flesh or "double eyelid", whether the welding part is appropriate, whether the spot welding is too large or not. Too small, whether there is weak electric welding or electric welding

To distinguish the quality of the bearing, you can start from the appearance of cracks, black spots or peeling and expansion. If the flip body cannot be a ball bearing and can rotate easily, it will lead to bearing noise and rotation accuracy. If it is reduced, it may even lead to equipment failure.