All kinds of mechanical scars, such as abrasions, scratches, pressure injuries, bruises, etc., will cause poor bearing installation, cause eccentric loads and stress concentration, and cause a decrease in rotation accuracy and service life.
Corrosion, black skin, and pitting, the latter two are defects that are easy to store moisture and dirt, and are most likely to develop into rust. Corrosion is a source of pollution that leads to poor installation, early wear and fatigue. Severe rust will make bearings obsolete.
Various cracks, such as raw material cracks, forging cracks, heat treatment cracks and grinding cracks, etc., these cracks will become a source of stress concentration and expand rapidly during the operation of the bearing in the future, causing the bearing to rupture, affecting the bearing life and working safety great. As a matter of fact, for important bearings, the bearing factory has carried out 100% magnetic or radiographic inspections on its component parts.
Peeling and folding, the local defects of these two defects are not tightly bonded to the base metal, and there are often decarburization or carbon depletion around them. The material is easy to fall, dent, or wear, which is detrimental to bearing life and accuracy.
The quality of the riveting or welding of the cage, mainly to observe whether the rivet head is misaligned, skewed, slack, lack of meat or “double eyelid”, whether the welding position is correct, whether the welding point is too large or too small, whether it is not welded well or over welded Causes the phenomenon of jammed rolling elements.
Post time: Jan-28-2021