Abstract: A valve body pressure formed from pipe components includes an annular portion for receiving a ball closure member. A pair of conduit portions are connected to the annular portion and the ball. A stem housing for rotatably supporting a valve stem extends up from the annular portion. The stem housing, annular portion, and conduit portions are welded to form the unitary valve body. The conduit portions are integrally connected to end fittings adaptable to connect identical or different grades of polyethylene pipe or metal pipe to polyethylene pipe. The internal surface of the conduit portion includes gripping teeth and O-ring seals that frictionally and sealingly engage the surface of the polyethylene end fitting. The valve can include a metal end fitting and a polyethylene end fitting. The polyethylene end fitting is connected by butt fusion or electrofusion coupling to polyethylene conduit, generally 6 inches in diameter or larger for use in a natural gas distribution system.

Abstract: A valve body has a valve seat in the lower portion of a valve chamber with inlet and outlet openings communicating with the chamber for the flow of fluid therethrough. A valve assembly has a valve disc arranged to move into and out of abutting relation with the valve seat and a disc cap connected to the upper portion of the valve disc. A valve stem supported for axial, reciprocal movement within the valve chamber has a threaded upper portion connected to a rotatable bushing and a threaded lower portion connected to the disc cap. A flexible metal diaphragm assembly separates the valve chamber into the upper and lower portions and includes an axial bore through which the lower portion of the valve stem extends. A diaphragm stem clamp threadedly engaged to the valve stem lower portion securely abuts the top surface of the diaphragm.

Abstract: A valve member is axially supported for reciprocal movement within the lower portion of the chamber of a valve housing. The chamber lower portion is sealed from the chamber upper portion by a flexible diaphragm assembly. The valve member includes a cap maintained in abutting relation with the lower surface of the diaphragm assembly. A valve stem is coaxially aligned with the valve member above the diaphragm assembly and includes a head portion that abuts the diaphragm assembly opposite the cap. Downward movement of the valve stem is transmitted through the diaphragm assembly to downwardly move the valve member into sealing relation with the valve seat. The valve is opened by advancing the valve stem upwardly within the chamber. A Belleville spring assembly surrounding the valve member urges the valve member to move away from the valve seat to open the valve.