Railway freight rolling bearing appearance defects - — pitting

Railway freight rolling bearing appearance defects - — 2020 - pitting 03 - 25 railway wagon wheel with bearing is usually made by the inner and outer ring, roller, retainer, grease and seal etc. Railway freight car rolling bearing is a kind of typical contact fatigue under parts, all in accordance with the use of the site may find fault forms bearing damage can be divided into the following several types: stripping, raceway grinding skin, race, color, race, pitting, corrosion, raceway surface rough, electric erosion, and bearing saddle poor contact, crack or split, knock against injury, micro wear, dent, indentation, etc. Mixer definition of railway freight car rolling bearings parts that are scattered or clustered on the surface of small pit. Pieces of hurt characteristics of raceway surface scattered or gather the tiny spots, have a certain depth, and handle, more appear in the raceway surface, sometimes occur in the roller ball base or inner ring roller guide surface. More than pieces of hurt parts pitting appeared in railway freight car roller bearing inner and outer ring raceway and roller rolling surface, also appeared in the roller ball base or inner ring roller guide surface. Mixer belongs to the nature of the contact fatigue damage reason and under the influence of the cycle of rolling contact stress, form the micro crack in the metal surface, and gradually developed into the pits of tiny stripping. Low component working surface or the surface layer of tiny area there are inclusions or large granular carbides, and initiation of small area under contact loading. Low improper assembly or too poor lubrication contact stress effect also can produce small dot. Mixer degree classification low pitting diameter & le; 0. 2 ㎜, defect category A or B; Low pitting diameter> 0. 2 ㎜ and touch, for defect category C. （ Source: the resources of railway vehicle platform)