Analysis of the reasons for the sealing device specified in the electric ball valve regulations

When the electric ball valve is opened, the pressure inside the chamber is lower than the working pressure, so the pressure of the medium on the packing is very small. The packing must be able to withstand working pressure when opened. The top sealing structure prevents the pressure of the working medium from acting on the packing, prolongs the life of the packing, and prevents valve leakage.
Another characteristic is that if there is a leakage in the sealing packing, the electric ball valve can be fully opened to seal the top, so loosen the packing ring or packing ring, add more packing, and then use the valve packing to compact the cover. Electric ball valves must be equipped with sealing devices as they are tightly packed to ensure no leakage.