With the development of social economy, the use of valves is more and more extensive. The valves used in the pipelines are various in variety and structure, and they are the most vulnerable pipeline accessories. The maintenance of each valve should be based on the specific The structure is carried out, the valves used in the pipeline are various in variety, the structure is different, and it is the most vulnerable pipeline accessory, and the maintenance of each valve.
Valve body and bonnet inspection valve body and valve cover are the outermost closed casing of the valve to withstand the pressure of the medium, the additional force during operation, the weight of other parts of the valve, and the tightness of the flange or thread at the joint. Force. Valve body and bonnet require certain strength and rigidity. Their damage is mainly caused by medium corrosion, erosion and mechanical damage. When the wall is thinned due to corrosion or erosion, it will affect their strength. And when it is rigid, it cannot be repaired and should be replaced.
During maintenance, the valve body and bonnet should be tested for hydraulic strength first, and then checked for tightness with water, compressed air, kerosene or other media. The defects of the valve body and bonnet are generally repaired by welding, depending on the material. Corresponding welding rod and welding process. Defective metal should be cleaned before welding, and after inspection and repair, it should be inspected and trimmed, and stress relief.
Inspection and repair of the filling chamber The inspection of the filling chamber includes the replacement of the packing and the inspection and repair of the stuffing box. When using the packing, the conditions of use and the medium must be considered. In general, the oil infiltrated asbestos packing is suitable for air and steam at a certain temperature. Water and heavy oil products. Graphite asbestos packing can be used under high temperature and high pressure conditions, especially for graphite asbestos packing with steel wire. The medium with high temperature and constant temperature can be used with asbestos and lead packing. Strong corrosive medium can be used. Teflon asbestos packing or teflon weave.