Truck Cylinder Liners for Diesel Engine

详情

The companys cylinder liner generallyapplies the materials of wear-resistant alloy cast iron containing chromium or boron, such as HT25-47, HP-CuCrMo, etc. The inner surface of the cylinder liner is also sometimes chrome plated (loose hole chrome plating, chrome platedatoil storage outlets), and nitriding or phosphating treatment to improve wear resistance. Theinner surfacehardness of cylinder liner is usually greater than HB200, and has a good match withthehardnessofpiston ring. The inner surfaceshould haveappropriate roughness to make it have a certain oil storage capacity and running-in performance. The inner surface should be of sufficient roundness and cylindricity accuracy, and the mounting support shouldhave a high positional accuracyagainst the inside bore center.
The inner surface of cylinder is easy to wear because of high temperature and high pressure gas and contact with pistons at high-speed motion. In order to improve the wear resistance and prolong the service life of the cylinder, different cylinder structure and surface treatment methods are provided. There are three types of cylinder structures: no cylinder liner type, dry cylinder liner type, wet cylinder liner type.
Non-cylinder liner type means that no cylinder liner body is embedded, andthe cylinder body is directlyworked out ofthe body,which hasthe advantages of shorteningthe cylinder center distance andreducingthe size and theweight of the body. But the cost is high.
Dry cylinder liner is not in contact with the coolant, with the wall thickness of 2~3mm, the outer surface and cylinder liner seat holeinnersurface must be refined to ensure the necessary precision and easyremoval, whichhas the advantages ofhigh rigidity, small central distance of the cylinder, light weight and simple processing technology. The disadvantage is that the heat transfer is poor, the temperature distribution is uneven, and the local deformation is easy to occur.
The outer wall of wet cylinder lineris in direct contact with the coolant,withthe wall thickness of 5~8mm,whichrealizes the radial positioningbyusing the upper and lower positioning ring,and realizesaxial positioningwith the help of correspondingbearing surfacemating between the upper flangeof cylinder linerand the top of the body,which has the advantages of the absence of sealedwater jacket on the body, easy casting,goodheat transfer,eventemperature distribution and easy repair withoutremoving theenginefromthe vehicle when replacing the cylinder liner.Butthe body stiffness is poor, and easy to leak.