Electrical insulating pipe coupling

Claim 1

IN A PIPE JOINT, THE COMBINATION COMPRISING: A HOLLOW METAL BODY HAVING A TERMINAL PORTION PROVIDED WITH AN ANNULAR PACKING RECESS TERMINATING AT ITS INNER END IN AN ANNULAR SHOULDER SURROUNDING A CONCENTRIC FLOW PASSAGE, THE SIDEWALL OF SAID RECESS BEING SUBSTANTIALLY CYLINDRICAL; A RELATGIVELY-THIN SUBSTANTIALLY-RIGID WASHER OF ELECTICAL INSULATING MATERIAL ADAPTED TO BE DISPOSED IN SAID RECESS IN ENGAGEMENT WITH SAID SHOULDER TO FORM AN ABUTMENT FOR A CIRCUMFERENTIAL FLANGE, OF SMALLER DIAMETER THAN SAID RECESS, ON THE TERMINAL END OF A METAL PIPE ADAPTED TO EXTENDED INTO SAID RECESS FOR COUPLING TO SAID BODY; A RESILIENT DEFORMABLE ANNULAR GASKET MEMBER OF ELECTRICAL INSULATING MATERIAL ADAPTED TO BE DISPOSED IN SAID RECESS, SAID GASKET MEMBER HAVING AN INNER ANNULAR END SURFACE ADAPTED TO ENGAGE THE OUTER FACE OF THE PIPE FLANGE, AN OUTER ANNULAR END SURFACE, AN INTERIOR SUBSTANTIALLY CYLINDRICAL SURFACE ADAPTED TO SNUGLY EMBRACE THE PIPE, AND AN EXTERIOR SUBSTANTIALLY CYLINDRICAL SURFACE ADAPTED TO ENGAGE SAID RECESS SIDEWALL; A SUBSTANTIALLY RIGID ANNULAR FOLLOWER MEMBER OF ELECTRICAL INSULATING MATERIAL HAVING A SUBSTANTIALLY CYLINDRICAL EXTERIOR SURFACE OF SLIGHTLY SMALLER DIAMETER THAN SAID RECESS, A SUBSTANTIALLY CYLINDRICAL INTERIOR SURFACE ADAPTED TO CLOSELY FIT THE PIPE, AN INNER ANNULAR END SURFACE, AND AN EXTERIORLY REDUCED OUTER SUBSTANTIALLY CYLINDRICAL EXTENSION FORMING AN OUTWARDLY-FACING FRUSTO-CONICAL ANNULAR SHOULDER, SAID FOLLOWER MEMBER BEING ADAPTED TO EXTEND INTO SAID RECESS