Five Precautions in Bearing Operation

Severe in touch with the surface of the metal stripping and present a large area of messy scratches; usually, bearing mechanical damage refers to the alloy surface of the axle tile presents different levels of grooves. Touch surface damage and ablation phenomenon exists together constitute the bearing mechanical damage is the primary reason for the bearing surface is difficult to constitute the oil film or oil film is severely damaged.

I. Mechanical damage
Severe in touch with the surface of the metal stripping and present a large area of messy scratches; usually, bearing mechanical damage refers to the alloy surface of the axle tile presents different levels of grooves. Touch surface damage and ablation phenomenon exists together constitute the bearing mechanical damage is the primary reason for the bearing surface is difficult to constitute the oil film or oil film is severely damaged.
Second, bearing cavitation
Surface layer of plastic deformation and cold hardening, sliding bearing in the cylinder pressure impact load repetition effect. Part of the loss of deformation ability, gradually constitute grain and expanding, and then followed by the fall of the abrasive chips, loaded surface layer constitutes a cave. Usually when the tiles attack cavitation, the first pit, and then this pit gradually expand and lead to the alloy layer interface cracking, cracks along the interface of the parallel direction of expansion, until the drop stop. Sliding bearing cavitation is the primary reason because of the oil groove and oil holes and other elements of the layout of the cross-section of a sudden change in the oil flow caused by the intense dislocation of the oil flow dislocation of the vacuum zone constitutes a bubble, and then because of the pressure rise, bubble collapse and cavitation occurs. Cavitation usually occurs in the bearing high load area, such as the crankshaft main bearing on the lower tile.
Third, fatigue pitting
Because the engine overload operation, bearing fatigue pitting is. Make the bearing operation overheating and bearing clearance is too large, constituting the middle of the bearing fatigue damage, fatigue pitting or fatigue drop. This damage is mostly due to overloading, bearing clearance is too large, or smooth oil is not clean, mixed with foreign matter inside. Therefore, the use of should pay attention to avoid bearing overload operation do not too low or too high speed operation; idling to adjust the engine to a stable condition; to ensure that the normal bearing clearance, to avoid engine speed is too high or too low; view, adjust the cooling system operation, to ensure that the engine's operating temperature is suitable.
Fourth, bearing alloy corrosion
The chemical impurities (acidic oxides, etc.) in the smooth oil make the bearing alloy oxidize and generate acidic substances, and the bearing alloy corrosion is usually in the area of impure smooth oil. Lead to bearing alloy partially fall, constitute irregular small cracks or small pits. The primary reason for bearing alloy corrosion is improper selection of lubricating oil, poor corrosion resistance of bearing materials, or rough engine operation, the temperature is too high.
Fifth, bearing melting
Constitutes part of the high temperature, journal and bearing conflict between the small raised metal surface direct touch. Smooth lack, poor cooling conditions, so that the bearing alloy black or part of the melt. This problem is often caused by the journal and bearing cooperation is too tight; Smooth oil pressure is also simple to make the bearing incineration.

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