Improvement On The Piston Ring-Cylinder Liner Of CA6DE1 Diesel Engine

For the increasing demand of emission legislation and technology of turbocharger or turbocharger intercooler being used to diesel engine universally, which leads to higher mechanical load and thermal load , and at the same time,the market is intensely competitive, the customers need higher reliability and durability of the diesel engine , wear-resistance of the pair of piston ring—cylinder liner becomes more and more important and is the main factor affecting the diesel life .It directly decides more and more diesel engine's durability and mileage of heavy repair. So many automotive engineering technologists of home and overseas have done a lot of research work on how to resolve the question of wear-resistance of piston ring—cylinder liner, and the research is going on now. In order to meet new emission legislation, CA6DE1 series diesel engines produced by DL Diesel Works are designed to replace CA6110 diesel engines. After CA6DE1 was on sale in 2002, the customers' response is very good, but someone thinks that it has early abrasion phenomenon. This paper uses the method which combines the wear-resistance test and table test, and studies the wear-resistance capability of the friction pair of CA6DE1 diesel engine.The lab wear test is performed on a reciprocating friction abrasion machine which with high temperature and high speed, the example is cut from the new cylinder, the example is asked to keep the surface and the machining state of primal facies. The radian of outer circle of the special Piston ring is machined according to the cylinder inside surface's. 7 kinds of cylinders is selected and the piston-ring example with spray-molybdenum is machined specially .The capability of the cylinder is mainly evaluated in two aspects of resistant scratch and wearability. The scratch test has 37 pairs effective example and the wear test has 54 pairs. The quantitative analysis is done respectively according to the friction-time curve analysis and contour line analysis. The best cylinder material with general capacity is found out: cast iron which comprise boron phosphor alloy + isothermal quencher .Then the contrast tests of engines with the liners are carried on. After 12 hours' table quick wear test validation, the life of the friction with new material liner is 3 times of the old.At the aspect of wear capacity of liner, the results of table test and lab wear test are consistent. This proved that lab wear test machine can simulate the wear form of the friction pair very well.The new method in which lab wear test and table quick wear test are combined only needs 1-2 cycles table reliability test. Comparing to the old table test method with 1000 hour wear, the new method uses much less test time , and shortens the test cycle, reduces the test expenditure.