In boiler equipment, the valve can play the role of opening and closing the pipeline, controlling the flow direction, adjusting and controlling the parameters (temperature, pressure and flow) of the conveying medium. The valve is a control component in the fluid conveying system, which has the functions of cut-off, regulation, diversion, prevention of backflow, voltage stabilization, diversion or overflow and pressure relief. According to the specific function of the valve, it can be divided into shut-off valve, check valve, regulating valve and other models.