Why the internal combustion engine crankshaft bearing friction power can damage?

Internal combustion engine crankshaft bearing is one of the main friction pair of internal combustion engine work, its working process will form and dynamic radial lubricating oil film, the crankshaft main bearing working condition directly affects the reliability of internal combustion engine, durability and economy, at the same time also affects the working life of internal combustion engine. A crankshaft bearing system of tribological behavior and dynamics behavior happened at the same time, during which there is a nots allow to ignore to better fusion effect; As a result, the friction power loss is inevitable. Why the internal combustion engine crankshaft bearing friction power can damage? In 崋 bearing network ( ） According to the understanding of the knowledge sharing is as follows. According to the specific analysis of the internal combustion engine crankshaft bearing working condition, learned that bearing friction power might damage the reasons mainly include the following: 1, as the journal and the decrease of the surface roughness of bearing, main bearing friction power loss decrease obviously, reaches a certain level of roughness, the friction power loss of the basic remain unchanged; Therefore, in order to reduce friction power loss, should be appropriate to improve the journal and bearing surface roughness level. 2, lubricating oil temperature rise, main bearing friction power loss decreased, and decreased with temperature change is bigger, but if the temperature is too high, viscosity of lubricant, the bearing capacity of the bearing will decline; In guarantee under the premise of bearing capacity, therefore, appropriate increase temperature is helpful to reduce the friction power loss. 3, the same conditions, internal combustion engine speed increase, the main bearing friction power loss increased significantly; Therefore, within the scope of reasonable speed should choose low speed bearings in order to reduce the friction power loss. 4, different main bearing clearance on the influence of the main bearing power loss is different, with the increase of clearance, there is a downturn in the power loss if the bearing gap is too small, the friction power loss increased rapidly; Therefore, the engineering practice should be avoided in the gap is too small. 5, fuel delivery advance Angle changes have an impact on the main bearing friction power loss, within a certain range, the power loss is relatively close, such as beyond a certain range of the power loss is bigger. 6, main bearing in internal combustion engine design phase, under the premise of considering the friction power loss, should first consider the bearing surface roughness, bearing clearance is the main factor affecting the internal combustion engine main bearing friction power loss; Second, at a given speed and temperature range, decrease the main bearing working speed and increasing the working temperature of lubricating oil is beneficial to reduce the bearing friction power loss.