Product overview: the opening and closing parts of the stop valve are cylindrical disc, the sealing surface is flat or conical, and the disc moves in a straight line along the center line of the fluid. The national standard stop valve is only suitable for full open and full close. Generally, it is not used to regulate the flow. When it is customized, it is allowed to regulate and throttle. The pipeline with nominal pressure of 1.6mpa-16. OmpA and working temperature of - 29-550 ℃ in petroleum, chemical industry, pharmaceutical industry, chemical fertilizer, power industry and other working conditions shall be cut off or connected with the pipeline medium. Flange stop valve is driven by manual, gear drive, electric, pneumatic, etc.