Before the valve is installed, it is necessary to check whether the surface and moving parts are damaged, and then install the valve on the pipeline according to the requirements. During daily use, the staff needs to maintain the moving parts exposed to the air, such as applying lubricating oil. When there is a problem with the valve, the staff first needs to close the pipeline, then check the inside of the valve to find out the problem, and then carry out corresponding repairs; sometimes the sealing surface needs to be polished, and sometimes the valve stem or gate needs to be replaced.