The reason why the operation of the hydraulic press does not respond

If the spring of the reversing valve is too soft or short, it will affect the working position of the valve core and normal reset, so that the hydraulic press system can not work normally. What is the reason why the operation of the hydraulic press does not respond?

1. Wear and tear

The motion pairs of hydraulic spool, valve sleeve, valve body and other mechanical parts constantly produce friction during use, which makes the size, shape and surface quality of the parts change and fail. These can cause the valve to fail.

2. Fatigue

Working under long-term variable load, the spring in the oil pressure valve will become soft, shorten the length of the spring or break the whole because of fatigue; The spool and seat will also be cracked, spalling or other damage due to fatigue. The bending deformation of the valve spool will make the valve reversing action difficult to carry out normally. The pilot taper valve (or pilot small ball valve) at the relief valve is not tightly sealed due to wear, and the pressure can not be adjusted normally. The wear of the pilot valve of the pressure reducing valve will make the valve work unstable and even cannot adjust the pressure. The spring on the main slide or pilot valve of the relief valve is tired or broken, and the system pressure will not meet the requirements. If the matching gap between the spool and the valve hole is too large, pressure shock will occur. The spool of the relief valve is bent or deformed, which will make the spool move inflexible and cause the pressure of the hydraulic press system to be unstable.

3. Deformation

When the residual stress of the hydraulic valve parts in the processing process and the external load stress in the use process exceed the yield strength of the parts material, the parts are deformed and can not complete the normal function and fail.

4. Corrosion

There is too much water or acid in the oil pressure oil, and after a long time of use, it will corrode the relevant parts of the oil pressure valve, making it lose its due accuracy and failure. The wear or deformation of the solenoid valve spool will reduce the efficiency of the valve, and the dirt is easy to enter the gap or deformation, so that the valve spool will produce gas jam phenomenon. Unloading valve spool bending deformation will make the spool action slow, so that the system from unloading to working pressure or working pressure to unloading transition process slow. The check valve of the one-way throttle (speed regulation) valve is partly worn, the seal is not strict, and some oil flow will flow away through the check valve, affecting the sensitivity of speed regulation.