3893718 is referenced by 99 patents and cites 6 patents.

A pipe coupling including a collar provided with external flanges initially larger than the normal diameter of the collar which, in the course of installation, are constricted until their outer surfaces are essentially flush with the normal surface of the collar causing the portions radially inward of the external end flanges to inbed into pipe ends inserted in the collar. An insulating sealing sleeve is interposed between the collar, including the external flanges and both of the pipe ends to form, when compressed, a seal between the collar and both pipe ends as well as an insulation barrier between the collar and one of the pipe ends. A second insulating sleeve including a flange is disposed within the pipe ends, the flange being disposed between the pipe ends.

Constricted collar insulated pipe coupling
Application Number
Publication Number
Application Date
November 23, 1973
Publication Date
July 8, 1975
Powell Jonathan S
Lyon & Lyon
F16l 11/12
F16L 25/03
F16L 25/00
F16L 13/14
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