Main failure mode of the rolling bearing ( 2)

Three, plastic deformation under the effect of external force and temperature, the bearing parts surface local plastic flow or the overall deformation, cause the failure caused by a complete set of bearing cannot work normally referred to as the deformation and failure. In the case of the heavy work load, the bearing has received large impact load or static load, or because the thermal deformation caused by the additional load, or when there is a high hardness of foreign body of shooting, will be in a way form dents or scratches on the surface. This will make the bearing severe vibration and noise during operation. And and, and produce the above four mark, which caused by the impact load is likely to further the cause of near surface left to fall. Such as cage warp, contorted, pocket hole stretched or box shaped cage deformation can cause of bearing early failure. Other bearing friction surface plastic scratch can also cause vibration and noise increased, the temperature rise, increasing the bearing early failure. Four, corrosion medium metal surface with environment bearing parts chemical or electrochemical reaction, thus the surface damage of the bearing and shaft bearing failure, known as corrosion failure. Will have chemistry on surface of bearing parts of environmental media are air, moisture, the oxidation products of fuel and lubricating oil ( Acids, ketone, ethanol, etc. ) As well as the oxidation product vapor, etc. When water direct invasion into the bearing can cause bearing corrosion. On the other hand, when bearing stop working, the temperature fell to a low temperature bearing, the moisture in the air condenses into water droplets on the adsorption on the surface of bearing can also cause corrosion. In addition, when bearing inside is energized, the points of contact between the raceway and rolling body, an electric current passes through a thin oil film cause sparks, make the surface of partial melting, formed on the surface of the corrugated four convex gravamen. Usually bearing surface corrosion can be divided into the dielectric corrosion, organic acid corrosion and other medium corrosion, Such as lubricating oil containing sulfide) And current corrosion, etc. Corrosion on the bearing parts, metal surface oxide film or corrosion holes, make the surface presents partial or full color. Hard brittle loose oxide film and corrosion of reactants flaking under load, bearing surface and born into pits or work surface coarsening, five wear or corrosion and corrosion fatigue invalidation fracture, fracture bearing parts will cause a sudden failure accidents, cause bearing fault is the main reason for the overload and defects of two factors. Due to the material strength limit loads over bearing parts, bearing parts caused by fracture was overload fracture. Overload may be the cause of the host fault, also may be bearing structures or installation is unreasonable. Bearing parts, moreover, there is a micro crack, shrinkage cavity, large bubbles and external defects such as inclusions, under normal load, at will, in the defect on fracture, referred to as a defect fracture. Bearing ring and roller in forging, heat treatment and grinding process of overheating, burnt, local surface crack may cause burns and bearing failure. Especially when grinding burn in the check is not easy to find, have a ferrule grinding burn injury suffered stamping or vibration may rupture