Abstract: An improved connecting device for of securing a pipe fitting of one material to a pipe of another. This invention provides a connector body with an insert fitting which does not leak therebetween. Further, the invented device has an integral annular flange, which extends into the surrounding body thereby preventing the body from expanding with heat and slipping with relation to the insert upon engaging the fitting with a nipple or other pipe material, and twisting forcefully.

Abstract: A plastic pipe seal for dual wall plastic pipe includes a plastic single piece or multi-piece fitting formed of rigid plastic sheet. At each inlet to the fitting, two formed grooves are radial to the line of flow through the fitting. The groove closest to the fitting inlet mates with a corresponding groove on the pipe, which groove receives a mechanical retainer. A second radial groove spaced from the retaining groove holds a gasket sealing device which provides a seal between the inside of the fitting and the outside diameter of the pipe. The retainer can be an extruded or molded plastic or metal spring cut to appropriate size, or a dual durometer structure, which allows for compression to a solid retainer.