Analysis of several common faults in the hydraulic system (a)
Because the hydraulic transmission compared with other transmission type, has obvious advantages in the control precision and automation, convenient operation and labor saving aspects, so the hydraulic transmission has become the main type of transmission is widely used. At present, there is a trend of fully hydraulic engineering machinery, such as full hydraulic double steel vibratory roller, stabilized soil road mixer, cement and asphalt paver, etc.. However, due to the various components, auxiliary devices and oil in the hydraulic system are mostly closed in the shell and pipeline, it is not as intuitive as the mechanical drive, which makes it difficult to remove the obstacles. The common faults in hydraulic transmission system are oil leakage, pressure imbalance and system failure. Here are the reasons for these failures to be analyzed.
1, oil leakage
Oil leakage is a common problem in the hydraulic system. At present, there are oil leakage phenomena in the hydraulic equipment both at home and abroad. Not only has it caused pollution to the environment, but also caused a lot of waste of resources. The reasons for oil leakage involve the following aspects.
(1) machining and assembly accuracy of components
The hydraulic components usually work in the medium and high pressure environment, and the machining accuracy of the components directly affects their sealing performance. If the gear pump end clearance requirements between 0.02~0.05mm, is that in order to prevent the pump itself within the vent valve in the valve plate; and mounting plate usually the clearance seal the gap to poor equipment, poor quality of employees), led directly to the quality of hydraulic components relative to foreign element difference is far, so to reduce leakage components to improve the level of processing machine. Another reason can not be ignored is that after the repair or processing of hydraulic components, improper assembly, so it should improve the technical level of the industry personnel, and strictly in accordance with the assembly standards of hydraulic components to be assembled.
(2) selection and installation of seals
Whether the hydraulic parts are leaking or not is closely related to the selection and installation of seals. Usually a good seal on the seal, with the system pressure seal pressure automatic regulating system; friction seal relative motion components with smaller; the seal should have good elasticity; the permanent deformation is small.
A bad seal type selection is improper, the gap is too large or when placed lead trimming will make bad seal, size and speed, so the factors should be integrated into the system working pressure actuator movement type and speed and load characteristic of the system, the correct selection of seals.
(3) connection of components and pipelines
The oil leakage at the pipe joint is the most common fault, which can be removed and screwed again. In general, it is necessary to avoid the gasket to seal the oil leakage pipe joint, because the pad will enter the pipeline to become a new source of pollution. In most cases, the oil leakage of the pipe joint is caused by the poor initial assembly, such as the tight joint of the pipe joint.
