With the development of social economy, Ball Valve are used more and more widely. There are many types of Ball Valve used in pipelines, with different structures. They are also the most easily damaged pipeline accessories. The maintenance of each Ball Valve should be carried out according to the specific structure.
There are many types of Ball Valve used in pipelines, with different structures. They are also the most easily damaged pipeline accessories. The maintenance of each Ball Valve should be carried out according to the specific structure.
1. Inspection and repair of valve body and valve cover The valve body and valve cover are the outermost closed shell of the Ball Valve, which are used to withstand the pressure of the medium, the additional force during operation, the weight of other parts of the Ball Valve, and the tightening force of the flange or thread at the connection. The valve body and valve cover are required to have a certain strength and rigidity. Their damage is mainly caused by local defects caused by medium corrosion, erosion and mechanical damage. When the wall is thinned due to corrosion or erosion, which affects their strength and rigidity, it cannot be repaired and should be replaced.
During inspection and repair, the valve body and valve cover should first be tested for water pressure strength, and then their tightness should be checked with water, compressed air, kerosene or other media. The defects of the valve body and valve cover are generally repaired by welding, and the corresponding welding rods and welding processes are selected according to the different materials. The defective metal should be cleaned before welding, and it should be inspected and trimmed after welding, and stress should be eliminated.
2. Inspection and repair of packing chamber The inspection and repair of the packing chamber includes the replacement of packing and the inspection and repair of the packing box. When selecting packing, the use conditions and the medium must be considered. Generally speaking, oil-impregnated asbestos packing is suitable for air, steam, water and heavy oil products at a certain temperature. Graphite asbestos packing can be used under high temperature and high pressure conditions, especially graphite asbestos packing with steel wire has better pressure resistance. Asbestos plus lead packing can be used for high temperature and frequently changing temperature media. For highly corrosive media, polytetrafluoroethylene asbestos packing or polytetrafluoroethylene braiding can be used.
