The following will share with you the factors that affect the sealing performance of hydraulic valves.
The main cause of damage to sealing elements is impurities in the working fluid. These impurities grind between sealing elements, causing the valve to leak. Therefore, foreign countries have proposed hydraulic components of corresponding grades, and filters of corresponding precision should be used. They believe that the life of the 5μM oil pump sealing element can be increased by 10 times compared with the use of 10μM if a filter with a filtration accuracy of 3/μM is used.
But the hydraulic support valve, the working environment is very bad. In the coal mining face, the total length of the oil pipe is more than 1,000 meters, and there are more than 4,000 joints and sockets, and the liquid tank has no special dustproof facilities. There are a lot of floating impurities in the emulsion, and there are more coal powder, rock particles and iron filings at the bottom of the cylinder and the valve cavity. Inlet valve core and valve seat, due to frequent opening and closing, high liquid flow rate, the seal will soon fail. Practice has proved that it is very difficult to reduce the contamination and impurities of the hydraulic system of the support. Some people once imagined that a high-pressure filter should be used in the emulsion pump station, and a small filter should be added at the inlet of each support. But it was quickly blocked during work, resulting in a cutoff.
On the other hand, with the development of hydraulic support technology. Higher requirements are placed on the performance of the valve and the service life of the valve. At present, the life of a hydraulic valve is measured by the total flow of the emulsion through the tested valve and the number of times the valve is opened and closed with a 120-mesh filter and a magnetic filter device installed. But in fact, the indoor type test is quite different from the actual work results in the well. At present, the formal experiments in many countries have increased the anti-pollution requirements. Some are mixing appropriate coal powder in the emulsion, and some are adding mechanical impurities. To this end, it is necessary to use a new type of sealing pair with strong anti-pollution ability and suitable for underground working conditions.
The service life of various hydraulic valves in the hydraulic support is very low. The foreign solution is to improve the filtration accuracy of the system and improve the quality of the emulsion, but the effect is not large. This paper analyzes the development process of the sealing pair of the bracket valve, and discusses the relationship between the material of the sealing pair and the sealing performance. It is pointed out that the sealing technology is the key to improve the service life of the hydraulic valve in the hydraulic support.
The above is the whole content of the factors that affect the sealing performance of hydraulic valves that I shared with you today. If you are helpful, please forward it.