A plug valve comprises a plug rotatable in a body of plastics. The plug fits closely within a thin walled metal can. PLUG VALVESThe valve body is formed by moulding around the can and plug, the can thereafter remaining fixed within the valve body, while the plug is rotatable in the can. Seals which are also embedded in the valve body during moulding project through the fluid passage openings in the can to engage the surface of the plug.Safety valves The provision of the can prevents damage to the plug during moulding of the valve body and prevents the plug from being bonded to the valve body, or the valve body shrinking onto the plug.Butterfly Valves An improved plug assembly for seating against a valve seat, the plug assembly being usable in a movable plug valve which controls the flow of the fluid through a conduit. The plug assembly includes an arm member, a plug member and biasing means. The arm member is adapted to be mounted for movement in the conduit and has an enlarged head. The plug member has a first face for sealingly engaging the valve seat and a rear face. The plug member further includes a recessed opening in one of the front and rear faces for receiving and retaining the enlarged head of the arm member for relative movement with respect thereto. The biasing means is disposed in the recessed opening and normally urges the enlarged arm head and the plug member into tight engagement with one another.

MORE NEWS