Engine bearings and characteristics of the causes of damage
As the world's top bearings SKF bearings, is widely used. Each industry, the damage characteristics are also different. Today we look at the engine bearing damage causes and characteristics.
(1), mechanical damage
Mechanical damage is a sliding bearing alloy bearing surface, with varying degrees of grooves, severe surface in contact with the metal strip and a large area of messy scratch; normal circumstances, the contact surface damage and ablation phenomena exist. Mechanical damage caused by the main bearing is difficult to form the bearing surface of the film or the film has been severely damaged.
(2), bearing cavitation
Bearing in cylinder pressure shock loading) under repeated, the surface layer of plastic deformation and work hardening, partial loss of deformability, and gradually form a pattern and continues to expand, and with the shedding of debris in the surface layer formed by the set point . Cavitation occursMR16 when the general bearing, came first pit, and then gradually expand this pit and cause cracking of alloy layer interface, the crack along the interface parallel to the direction of expansion, until the peel up. Bearing cavitation mainly due to fuel tank and the hole cross-section of structural elements such as sudden changes in oil flow caused by the strong disorder, disorder in the oil flow area of the formation of vacuum bubbles, then as pressure increases, the bubble collapse and the resulting hole corrosion. Cavitation generally occurs in high-load bearing areas, such as the crankshaft main bearings on the lower bearing.
(3), fatigue pitting
Bearing fatigue pitting is due to the engine work overload, overheating and bearing work makes the bearing gap is too large, causing the central bearing fatigue damage, fatigue, pitting or fatigue off. Most of this damage is due to overloading, excessive bearing clearance, or dirty oil, mixed with foreignLed lighting matter inside due. Therefore, the use of bearings should be taken to avoid overloading of work, not to low or high speed operation; the engine idle speed to adjust to the steady state; ensure proper bearing clearance, to prevent the engine speed is too high or too low; check and adjust the cooling system work, ensuring suitable engine operating temperature. Flanged ball valve
(4), bearing alloy corrosion
Bearing alloy corrosion is generally impure area for oil, lubricating oil in the units of chemical impurities (acid oxides, etc.) so that the bearing alloy oxidation and acid generation, causing some loss bearing alloy, the formation of irregular small holes or pits pit. Bearing alloy corrosion is mainly due to improper selection of lubricants, bearing materials, poor corrosion resistance, or rough engine, the temperature is too high.
(5), bearing pillow melting
Journal and bearing friction between the tiny bulge direct contact with the metal surface to form a local temperature, lack of lubrication, cooling under adverse conditions, the slide bearingbearing alloy or partial black pillow melting. This failure is often caused by too tight with the journal and bearing; lack of oil pressure bearings are also easy to burn.
(6), cylindrical bearings to go
Cylindrical bearings to go there is relative rotation of the bearing hole here. Cylindrical bearings to go after not only affect the cooling of bearings, the bearing surface of the alloy tends to erosion, but also the bearing back injury, severe burn bearings. The main reason is that the bearing is too short, Tenon damage, processing or installation does not meet the norms. |