After half an hour's work, the excavator's oil cylinder is hot, and the big pump and distribution pump, cleaning water tank and hydraulic radiator have just been repaired. If the water temperature is not high, two squares will be fine. What the hell is going on here? The possible reasons are as follows: 1. Check whether the pressure of excavator cold and hot machine is consistent. If a single action cannot be adjusted, adjust the main safety valve to 325kg.

LS pressure is basically close to the overflow pressure of the main pump. 2. After each boom of the excavator is extended as far as possible, block the oil inlet and oil outlet to see if there is any flow arm phenomenon. (that is, it automatically expands and contracts without action) If not, will it expand and contract under artificial pressure? 3. The one-way valve on the hot oil circuit of the excavator is invalid. The back pressure of the existing system is 0.3MPa, and the protection pressure of the oil cooler is 0.2MPa. It is reasonable to say that the back pressure of oil return should be as low as possible under the condition of meeting the back pressure requirements of the system. The oil temperature of the machine is too high, which may be: the resistance of the radiator is greater than the protection pressure, so that the hot oil in the oil return circuit directly returns to the oil tank without the radiator; The cleanliness of the system is poor, the check valve is stuck by dirt, the valve core is in the normally open position, and the radiator does not work; The opening pressure of the check valve cannot be guaranteed. On the premise of meeting the back pressure of the system, the check valve of 0.30MPa can be changed to a check valve of 0. 15MPa, and the protection pressure of the oil cooler can be increased to 0.35MPa.