The requirements for piston rings of Hitachi ZX200-3G hydraulic excavator are as follows:
1 full load operation before running in. Many repair plants will replace the engine after the replacement of the engine on the car immediately, this method is not good. After the ring of the engine must be hot before running, the running in time is suitable for 6h. Through the grinding, the outer rim and cylinder surface can be formed to fit the working surface of the working strip to improve the lubrication efficiency of the pair. The reliability and durability of the ring are better. Statistics show that the worn piston ring is 20% 30%. longer than the unworn piston ring.
2 operation maintenance
To reduce the starting times of the cold car, we advocate hot start. Because a part of the mixed gas that enters the cylinder when the cold car starts, it becomes cold, adsorbed on the surface of the cylinder wall and ring, and the ring works at low temperature for a long time, it is easy to corrode, the wear is aggravated and the life span is shortened. So the working temperature of the engine must be kept in a normal condition and the piston ring is in a good environment. To reduce unnecessary wear and tear, it is very necessary to "slow down and warm up locally".
If the speed is too low, the cylinder wall oil film is not easy to set up and the lubrication condition is poor, but the wear of the piston ring is accelerated. If the speed is too high, the mechanical load produced by the sports parts increases, the cylinder wall and the piston ring will increase, and the wear will increase under the action of high temperature and high pressure, and the speed is too low or too low. It is too high to prolong the service life of the piston ring.
Try to avoid overloading operation. The total quality of the car is directly proportional to the wear of the parts. The heavy overload operation will cause the engine overloading operation, cause early wear and tear, and the piston ring is prone to "stick" or "pull the cylinder".
Strengthen the "three filter" maintenance of.Lg dust into the cylinder, the upper cylinder can wear 0.Olmm, the piston grinding away the quality of 0.75g, so that the piston ring grinding to 0.009mm. as long as the engine cylinder sucks 30~40g dust, it will make the cylinder, piston and piston ring wear too much, and the gap between the ring and the cylinder wall will increase. In order to reduce the abrasive wear, it should be compulsory to reduce the abrasive wear and tear regularly. Maintain air filter, oil filter and gasoline filter, reduce harmful substances into cylinder, make piston ring work normally and wear speed down.
To overcome bad operating habits, such as stepping on the accelerator pedal, forcing the heating, often making the clutch half linkage, one foot clutch and shift, emergency brake parking, and the first acceleration after sliding, all will cause the lubrication condition to be worse, the wear of the piston ring is increased and the life span is shortened.
