Because of its simple structure and flexible layout, the hydraulic system has a good self-lubricating property, which is convenient to be used in conjunction with other transmission modes. At present in most of the devices of all kinds enterprise, therefore, widely used, I plant all the electrolytic PTM, casting machine, and key equipment such as tilting type mixer is used hydraulic transmission system. The hydraulic system is usually closed loop system, the fault of hydraulic system is difficult to find out is one of the main shortcomings of hydraulic transmission. The hydraulic system of the equipment should determine the cause of the failure as soon as possible and eliminate it in time to reduce the economic loss caused by the parking of the equipment. Engineering technicians need to perform fault analysis based on their own professional skills, hydraulic transmission basic knowledge, hydraulic component principle construction and basic circuit knowledge.
There are a lot of pressure gauges in the system pipeline design of the abnormal pressure. The pressure gauge is used to measure the reading, and the hydraulic component that causes the abnormal pressure can be determined by comparing with the normal value. The velocity of the throttle valve, the speed regulating valve and the variable pump variable mechanism are adjusted, and the velocity range value of the test execution component is determined by comparison with the design value. If the action state of the relevant actuator is normal, the abnormal reversing valve can be found, and the order of action and stroke control can be checked to find out the abnormality. Other abnormal vibration, noise, oil leakage, heating, etc., should not be busy shutting down, should be a second look at the three observation, identify abnormal parts and analyze the treatment.
Comprehensive application of hydraulic fluid mechanics knowledge can theoretically analyze the hydraulic circuit and any fault of hydraulic components. The following example illustrates the general search process for hydraulic failure. Fault name: hydraulic pump air hole; Malfunction: vibration, noise, cavitation; Main reason: pump suction pressure is lower than gas separation pressure, or suction air. Inference analysis: using the energy equation and continuity equation of flow of hydraulic pump oil absorption process is analyzed, can judge the pump causes of failure: tank of liquid surface pressure is too low, fuel tank air holes blocked oil pump suction mouth high fluid velocity through;
The pressure loss of the oil filter is too large -- the filter element is blocked; The length of the length of the pipeline is too high, and the oil temperature is low. The inner diameter of the suction pipe is too small; The local resistance coefficient is too large, the pipe bending, flattening, blocking and so on; The pump oil suction height is too high, the pipe seal is not strict, the suction pipe is immersed in the tank surface too shallow.