Sealed electrode assembly

Claim 1

AN INSULATED TUBE EAND ELECTRODE ASSEMBLY COMPRISING A TUBE WALL HAVING A RADIAL BORE, AN INNER LINING OF AN ELECTRICAL INSULATING COLD-FLOWING THERMOPLASTIC MATERIAL ON SAID WALL, THE LINING HAVING A RADIAL BORE OF LESS DIAMETER THAN AND ALIGNED WITH THE BORE IN THE WALL, A RIGID INSULATING BUSH WITH AN INNER CYLINDRICAL PORTION ADJOINING AN EXTERNAL FLANGE PORTION, THE INNER PORTION FITTING WITHIN THE RADIAL BORE WALL AND BEING OF A LENGTH GREATER THAN THE WALL THICKNESS SO THAT AN INNER END SECTION OF THE BUSH PROJECTS AT THE INNER SIDE OF THE WALL TO SEAT INTO THE LINING AND THE FLANGE PORTION ENGAGING THE OUTER SURFACE OF THE TUBE TO DEFINE THE INNER PROJECTION OF THE BUSH, AN ELECTRODE HAVING A SHANK AND AN INNER END HEAD FOR ELECTRICAL CONTACT WITH LIQUID FLOWING THROUGH THE TUBE, THE HEAD HAVING A POINTED RIDGE DISPOSED ADJACENT THE PERIPHERY OF THE HEAD AN BITING INTO THE LINING, WITH THE SHANK PASSING THROUGH THE BUSH AND HAVING A SCREWTHREADED SECTION PROJECTING EXTERNALLY THEREOF, AND A CLAMPING NUT ON THE THREADED SHANK SECTION WHICH IS TIGHTENED TO CLAMP AND GRIP THE LINING BETWEEN THE RIGID BUSH AND THE ELECTRODE HEAD TO PROVIDE A DOUBLE SEAL RESULTING FROM THE DEFORMATION OF THE LINING ON ONE SIDE BY THE INNER END OF THE RIGID BUSH AND ON THE OUTER SIDE BY THE ELECTRODE RIDGE, SAID ELECTRODE RIDGE PREVENTING THE COLD FLOW OF THE GRIPPED LINING PORTION FROM BETWEEN THE RIGID BUSH AND THE ELECTRODE HEAD.