新闻中心

Home page

2022

Key Process of Cylinder Linerless Technology for Automobile Engine Cylinder Block

Author:

The cylinder liner free technology of automobile engine originates from Europe. It uses thermal spraying technology to spray a layer of wear-resistant coating on the inner wall of aluminum engine cylinder to replace the traditional cast iron cylinder liner. It can not only reduce the weight and fuel consumption of the engine, but also significantly reduce the engine friction and improve the engine performance.
After the cylinder block is sprayed, the machining of the coating is very important. The coating must be honed to make the cylinder reach the correct diameter, roundness and surface roughness. A well-known European thermal spraying company made fine adjustments to the recommended technical specifications of the honed coating surface based on the engine oil consumption and fuel consumption reduction results obtained from engine test. In order to ensure that the pores will not contain any debris that may be mixed, it is important to properly clean the surface of the coating after honing. The hole edges need to be burred, and the honed surface should be free of scale.
After rough honing and fine honing, the inner surface of the cylinder bore can reach a mirror finish. Compared with the traditional honing of the cast iron cylinder liner, the honing surface of the coating is porous rather than reticulated. Because of the porous structure of the coating surface, the smoothness of the coating surface can be reduced to 25%, which is one of the reasons why the technology can save a lot of engine oil. The gently rounded small holes also reduce the area of oil exposed to the combustion chamber and piston ring, reduce the tangential force of the oil scraper ring, make the piston ring enter the hydrodynamic state faster, and significantly reduce the friction. Smaller engine friction means lower energy consumption for friction heat generation, reducing engine blowby and fuel consumption, and ensuring the highest working reliability. (Blowby refers to the "blow by" of gas in the engine from the piston ring clearance to the crankcase after the cylinder and piston are worn or deformed, which affects the engine power and fuel consumption.) Due to the inherent porosity of the final coating, the oil storage structure will not be worn off like the reticulated structure, but will open new pores as the wear develops towards the coating, so its life cycle efficiency will be significantly improved.

None