In recent years, with the rapid development of China's infrastructure industry, bulldozers and excavators have been widely used in earthwork, open pit mining and other projects. At present, the single-bucket hydraulic excavator with a bucket volume of 1m3 up and down is commonly used in Chinese projects. Most of them use a dual-pump dual-circuit full-power variable hydraulic system. The various actions of the excavator are achieved through hydraulic activities, which are achieved by the hydraulic energy pressure driving the motor and hydraulic cylinder, and the hydraulic oil pressure energy is converted by the engine into mechanical energy. Most failures of hydraulic excavators are related to the hydraulic system. The complete hydraulic system has actuators (cylinders, oil motors), power components (hydraulic pumps), hydraulic oil, control components (valves) and auxiliary components (oil pipes, tanks, filters) Cleaner, radiator, etc.) are composed of five aspects. Therefore, the engineers summarized the common failure methods of hydraulic excavator machines. At the same time, the common faults and solutions of hydraulic excavators are analyzed and shared with everyone!

　　Common faults of hydraulic excavator

　　1: No action on the whole machine

　　When the excavator breaks down, it should be investigated and judged in the following order. The first step is to check whether the hydraulic oil is sufficient. When the hydraulic oil is not enough, it will make the oil suction oil path unblocked, and the oil suction path will cause the hydraulic pump to fail to absorb oil or insufficient oil absorption, which will cause problems in the operation of the whole machine. The second step is to check whether the hydraulic pump is working properly. Hydraulic excavators usually supply oil to the system usually with two or more main pumps. Most of the failures of hydraulic systems are caused by mechanical failures. The main shaft of the pump cannot rotate. In the hydraulic system, multiple pumps have problems at the same time. Is very low. The third point is to observe whether there is a problem with the safety lock valve. When the safety lock valve is blocked or stuck, the oil will not pass through the PPC, which will affect the action of the main control valve, which will cause the whole machine to have no action. Fourth, check whether there is a problem with the main relief valve. A safety valve on the main control valve body is the main relief valve, which is the guarantee that the entire hydraulic system can withstand the highest pressure, which can protect the entire system. The method of detecting the valve body of the overflow valve is to touch the main valve body of the main valve with the hand, the temperature of the valve body of the overflow valve rises rapidly, and it can be judged that there is a fault.

　　2: A single action fails

　　When the movement of the excavator is out of control, the first step is to check whether the pressure of the entire system is within the normal range. Normally, the pressure of the pilot system is 5 MPa, but when the pressure is less than 2 MPa, the pilot control will fail. The three important components that make up this system are the handle pilot valve, relief valve and gear pump. When the pilot pressure is too low, most of the reasons are that the set pressure of the relief valve drops or the pressure of the gear pump does not go up, and occasionally there will be leakage of the valve stem cover of the multidirectional valve. This brings two phenomena. In the first case, the boom will be slow and weak during the process, and it will be slow and weak when turning. The other is that it cannot turn after a platform failure.

　　Excavator walking deviation

　　The first point is that during the work of the excavator, the hydraulic pump is an aspect that is more prone to failure. The excavator usually has two or more hydraulic pumps. Most of the cases are due to one pump A failure has occurred. The detection method is to exchange the two high-pressure discharge pipes of the hydraulic pump and observe whether the phenomenon of walking deviation is in the opposite direction. This can be regarded as a single pump failure. At this time, it is necessary to remove the damaged hydraulic pump for repair or replacement. The second point is that the oil leakage usually occurs on the safety valve of the walking motor. After the safety valve leaks, the internal pressure of the system will be too low, which will cause the speed of the walking motor to decrease, which will lead to the deviation of the walking. . The detection method is to replace the safety valves of the left and right walking motors to see if the direction of walking deviation is opposite. On the contrary, the fault is determined and repair or replacement of the safety valve is sufficient. The third point is that the internal spring of the walking main valve is broken or softened, and the valve core is stuck. These three conditions will cause the oil pressure to decrease. Observe and measure the walking pressure of the walking main valve, and repair or replace it after it is determined to be damaged.

　　Management of excavator oil

　　The quality of the oil used in the hydraulic system of the excavator will greatly affect the working life and durability of various components of the hydraulic system. The user must choose the correct hydraulic oil in strict accordance with the standards of the manual. According to the investigation and study, it is found that most of the hydraulic system failures are caused by small particles mixed into the system. Therefore, it is an effective way to improve the stability of the hydraulic system of the excavator to do a good job of obstructing particles and strengthen the maintenance and maintenance of the machine.

　　Maintenance of engine parts

　　Before starting the engine, some monitoring work should be carried out to check the oil level of the engine oil, check the coolant, check the fuel, check whether the air filter is blocked, check whether the wire horn is normal, and check whether the joints of the bucket are lubricated. When the machine is started, the speed should be increased slowly, so that the temperature of the body will be more evenly increased, and the oil will flow to the lubrication point. If the machine starts too fast, the lubricant will not be in place, which will cause the machine to burn down.

　　Pay attention to the regular maintenance of the excavator

　　To ensure that the machine is regularly repaired and maintained, the excavator must be maintained for 100 hours, 250 hours, and 500 hours. Perform a shift maintenance before and after work. Clean the leaking parts of the machine, and at the same time, check whether there is any failure or loose fasteners. When it has not been used for a long time, it should be sealed up and the work piece should be handled on the ground. And fill up the fuel tank, apply lubricant to each joint, etc. At the same time, add coolant according to the environment, and start the equipment once a month for maintenance. On the one hand, it lubricates various parts, on the other hand, it can charge the battery.