The cause of leakage of the valve Aside from the factors of valve body defects, the leakage of the valve is mostly caused by the seal damage of the middle flange or the stem packing. Chunlei Quntification Co.,Ltd , https://www.hychunleitools.com
The flange seal is mainly tightened with uniform bolts. If the bolt pre-tightening force is too small, the initial seal specific pressure required for the flange and the gasket is not obtained, or the bolt pre-tightening force is too large, so that the gasket is excessively deformed. The gasket rebounds insufficiently, and the seal pair will leak. After determining the temperature and pressure level of the valve, the selection of bolts and gasket materials becomes the key to the middle flange seal.
The external leakage at the valve stem is achieved by a stuffing box. Valve use conditions, stem material, packing properties and dimensions, and packing preload force all affect the sealing of the stuffing box. Erosion and abrasion of foreign matter, loss of elasticity or looseness of the filler is the main cause of failure of the stuffing box seal Â