Abstract: A plastic ring is spun onto the end of a plastic pipe, the heat of friction fusing the contacting surfaces between the ring and the pipe, forming a weld therebetween upon cooling. The ring provides greater radial rigidity at the end of the pipe, and carries a flange extending beyond the outside diameter of the pipe. A flexible sleeve is slipped over the ends of two adjacent sections of such pipe with the flanges in abutting position. Band-type clamps surround the sleeve overlying the rings and are tightened to effect a seal between the sleeve and the periphery of the flanges. The end rings are spun onto the pipe ends with either the inside or the outside diameter of the pipe engaging the interfering surface on the ring in two different embodiments.

Abstract: A valve body is formed of a section of flow pipe for connection to an open end on a flow pipe by means of a surrounding sealing sleeve and outer clamp. A valve body end cap is formed of a standard pipe cap with inlet ports drilled through the end thereof. A valve seat member is centrally mounted on the inside of the valve body end cap having a valve seat on the end opposite the mounting end. The valve seat member has a first predetermined height for positioning the valve seat a predetermined distance above the inside surface of the end cap. An internal step is formed on the inside diameter of the end cap at a second predetermined height above the inside of the end cap. A spacing ring is placed on the internal step having a thickness to provide for a desired difference between the first predetermined height and the sum of the second predetermined height and the spacing ring thickness. A diaphragm formed to fit the inside diameter of the valve body end cap is positioned with one face in contact with the ring.