What are the characteristics of automobile engine bearings

The function of the bearing in the engine is center positioning, bearing pressure and gravity, making the axis parallel, positioning the wheelbase, and reducing friction, so that the engine can run reliably and durable under different speeds, different loads, and different engine temperatures.

In addition to the use of ball bearings in certain special devices (such as the main bearing of automobile engines such as Tai Tuo La), automobile engine bearings generally use alloy bearings (Babbitt alloy). Alloy bearings used in different types and types of engines It is also different. Although automobile engine bearings before the 1930s were alloy bearings, this kind of bearing is integrated with the bearing housing hole (dead bush). With the continuous improvement of automobile engine power and rotation, this kind of fixed bearing has been It has been eliminated. The use of replaceable bearings in automobile engines makes the warranty more convenient and reliable, and the durability of the bearing shells is improved.

The reliability and durability of the bearing not only depends on its own material properties, but also depends on the shaft and bush clearance o shaft, bush clearance is too small and the shaft and bush abutment surface is not good, which will cause the bearing alloy to ablate and fluidize, or increase Resistance or bearing bush damage increases. Excessive shaft and bush clearances will cause the oil pressure to drop, and the oil will leak from the clearances, which will affect the oil supply of other parts of the engine. The lubricating oil circuits of large, small, and eccentric bearings are branched in series, and the oil entering the oil passage must be sufficient to generate enough pressure to meet the lubrication of other parts. Therefore, whether the engine oil pressure is normal or not depends on the clearance of the three-valve bearing bushes.

The bearing shell of the engine is two semicircles, which are adjustable alloy bearings. There is a layer of soft and wear-resistant alloy on the large and small tiles, so it is wear-resistant, stable in operation, and able to withstand greater pressure and impact, which is incomparable to rolling bearings.

The connecting rod is composed of a connecting rod body, a connecting rod cover, and a connecting rod bolt. Connecting rods are divided into large and small ends, the small end is the piston pin bearing hole, and the big end is the connecting rod bearing seat hole.