Blog

       Hydraulic assembly The manufacturer will explain the common hydraulic failures of excavators.

　　Hydraulic assembly manufacturer: Analysis of common hydraulic failures of excavators

　　 Hydraulic assembly Manufacturer: Analysis: Because the control of operating valves 1 and 2 causes all actions to be abnormal, the fault point should be in the common part of the two, that is, the part before the operating valve. According to the hydraulic system diagram, the reasons for the malfunction of the whole machine are as follows.

　　1. Insufficient hydraulic oil, unsmooth suction circuit (such as clogged suction filter), oil circuit becomes empty, etc., resulting in insufficient or inability of the hydraulic pump to suck in, leading to malfunction of the whole machine.

　　2. Pilot circuit failure. This failure only exists in servo-operated excavators and does not exist in mechanically operated excavators. If the pilot circuit fails, the pilot oil pressure is insufficient, the operating connection does not work, and the overall movement of the machine is poor.

　　3. Damage to the transmission connection between the hydraulic pump and the engine. In this case, the engine cannot drive the hydraulic pump, the pump port no longer outputs pressure oil, and the entire machine will stop working.

　　4. Severe wear or damage to the front and rear hydraulic pumps. The output flow and pressure of the pump are insufficient, the whole machine movement slows down or stops completely, leading to failure of the hydraulic pump power adjustment system.

　　When performing fault detection, the principle of "easy first, difficult later, outside first, inside later" should be followed. The specific methods are as follows:

　　First check the hydraulic oil level. If it is insufficient, add enough z to check whether the suction pipe is broken, whether the joints are loose, etc. These are the reasons for the oil pump part or serious air suction; check whether the suction filter is blocked or flat, etc. If so, please replace it. Check the four oil filter elements. When there are a large number of metal powders and particles, the hydraulic pump is damaged and needs to be checked.

　　In fact, not only the hydraulic pump is damaged, but also due to the damage of other actuators and bearings, etc., a large amount of metal powder and particles will also be contained in the return oil filter. Here, in order to study the reasons for the malfunction of the whole machine, we will ignore other non-universal parts. However, the hydraulic pump sometimes wears excessively due to long-term use, so even if there is no obvious abnormality in the return oil filter, it sometimes causes mechanical failure, so it should be noted. When the first two checks are normal, check the pressure of the pilot circuit. The reasons for the pilot circuit failure are the pilot pump, pilot oil filter, pilot oil circuit overflow valve, and oil circuit leakage in other parts. When the pilot oil pressure is insufficient, it is easy to occur. The system is still abnormal in the case of easy-to-difficult first. At this time, there are two situations: the whole machine does not work at all, and there is no load feeling when operating the machine. At this time, check the power transmission part between the pump and the engine, such as whether the transmission spline is damaged, etc. The movement is slow. Here is an example to analyze the fault phenomena and causes of various movements.

　　 Hydraulic assembly Tell you that the movement is slow, weak, or completely inactive (including unidirectional movement failure in reciprocating movement). According to the principle of easy-to-difficult fault detection, first check the pilot circuit and branch overload valve; under normal circumstances, check the operating valve to confirm whether the corresponding valve body is blocked; if normal, check the actuator and other related parts. For example, PC300 blood type excavator, when the turntable rotates during operation, it cannot stop suddenly, and it cannot rotate after stopping, but other actions of the machine are normal. Because it cannot rotate in two directions, the failure of the motor overflow valve and make-up valve can be eliminated; check the return oil filter, and no abnormality is found. I think the motor itself has no problem; after starting, operate the rotation, hear the sound of the engine and feel the load, touch the oil pipe of the rotary motor with your hand, and obviously feel the pressure oil entering the human motor, inferring that the operating handle, pilot circuit, and operating valve are working normally; as mentioned above, the turning reducer is the main suspect. During operation, if the rotating speed reducer connection suddenly cuts off the transmission due to equipment damage, etc., the connection between the rotating motor and the turntable is interrupted. After the turntable rotates, when the motor stops, it cannot brake the turntable, and the turntable continues to rotate due to inertia. After the z turntable stops, when the operating port rotates, even if the motor is working normally, the power will not be transmitted to the turntable, and the machine cannot rotate. Based on this assumption, after removing the motor assembly, the inner teeth of the rotary motor output shaft and the spline bushing are damaged and do not mesh, and the power connection between the rotary motor and the port rotating reducer is interrupted, resulting in the above-mentioned fault phenomenon.

　　Okay, today Hydraulic assembly The manufacturer will introduce it here first. If you need hydraulic equipment, please feel free to contact us, the hydraulic assembly manufacturer. The hydraulic assembly manufacturer wishes you a happy life!