First of all, different opening and closing parts have different sealing principles: the opening and closing part of the PPR gate valve is a gate, and the movement direction of the gate is perpendicular to the direction of the fluid. The PPR gate valve seals through the contact between the valve seat and the valve plate; the opening and closing part of the globe valve is a plug Shaped valve disc, the sealing surface is flat or sea-cone, and the valve disc moves linearly along the center line of the valve seat. The sealing surface of the disc and the sealing surface of the valve seat are closely fitted to prevent the medium from leaking along the gap between the sealing surfaces; the opening and closing parts of the PPR ball valve are driven by the valve stem and rotate around the axis of the ball valve to seal.
