초록 ▼

A preformed coupler for connecting plastic pipe to metal pipe comprises a convoluted tubular metal sleeve, a plastic tube extending part way into the metal sleeve, an annular gasket, and a retention means. The annular gasket, which encircles a portion of the plastic pipe, is compressed against the p

A preformed coupler for connecting plastic pipe to metal pipe comprises a convoluted tubular metal sleeve, a plastic tube extending part way into the metal sleeve, an annular gasket, and a retention means. The annular gasket, which encircles a portion of the plastic pipe, is compressed against the plastic pipe by the metal sleeve to form a fluid-tight seal. The retention means resists any effort to withdraw the tube from the sleeve. The free end of the metal sleeve can be telescoped over the end of the steel pipe to be joined, then the outer end of the plastic tube can be butt welded to the plastic pipe to be connected, and then the telescoped end of the sleeve can be welded to the metal pipe.

대표청구항 ▼

A preformed transition fitting suitable for field connection of one essentially cylindrical end of a plastic pipe and one essentially cylindrical end of a metal pipe, which comprises: a metal sleeve formed solely by a single annular wall, having a generally cylindrical central annular sleeve segment

A preformed transition fitting suitable for field connection of one essentially cylindrical end of a plastic pipe and one essentially cylindrical end of a metal pipe, which comprises: a metal sleeve formed solely by a single annular wall, having a generally cylindrical central annular sleeve segment having first and second longitudinal ends, a first generally frustoconical annular sleeve segment having a longitudinally inner end and a longitudinally outer end with the outer end forming a first outer end opening of smaller internal diameter than the internal diameter of the inner end of said first generally frustoconical annular sleeve segment, a second generally frustoconical annular sleeve segment having a longitudinally inner end and a longitudinally outer end with the outer end of said second generally frustoconical annular sleeve segment forming a second outer end opening of smaller internal diameter than the internal diameter of the inner end of said second generally frustoconical annular sleeve segment such that said second generally frustoconical annular sleeve segment can be telescoped over said essentially cylindrical end of said metal pipe and permit welding of the thus telescoped end of said metal sleeve to said metal pipe, and an annular shoulder segment joined to the first end of said generally cylindrical central sleeve segment and to the inner end of said first generally frustoconical annular sleeve segment, said annular shoulder segment being inwardly directed about its periphery to form an annular shoulder on the inside of said metal sleeve; a relatively short length of generally cylindrical plastic tube having first and second end portions and extending through said first outer end opening of said metal sleeve such that said second end portion of said plastic tube is positioned inside said first generally frustoconical annular sleeve segment in at least substantially coaxial relationship therewith while said first portion of said plastic tube is outside of said metal sleeve for bonding to said essentially cylindrical end of a plastic pipe, thereby forming an annular recess between the interior surface of said first generally frustoconical annular sleeve segment and the adjacent exterior surface of said plastic tube, the external diameter of said plastic tube being substantially as great as the internal diameter of said first outer end opening; an annular gasket positioned in said annular recess in sealing contact with the exterior surface of said plastic tube and the interior surface of said first generally frustoconical annular sleeve segment; and an annular retention element positioned in engagement with said annular shoulder and said second end portion of said plastic tube to retain said second end portion of said plastic tube within said metal sleeve.