Vorgefertigtes elektrisch isolierendes Zwischenstueck fuer Metallrohrleitungen

摘要

1286480 Electrically insulating pipe joint L BAGNULO 17 Dec 1969 [21 Dec 1968] 61452/69 Heading F2S An electrically insulating pipe joint comprises an enlarged socket 3 on pipe end 1 and a flange 4 on pipe end 2, the flange fitting within the socket and being separated therefrom by an electrically insulating sealing ring 6 seated in an annular recess 10 and by the annular space 22, the sealing ring 6 being partially overlapped with a spacer ring 5 of mechanically strong insulating material bonded into a recess 9 in the flange. The joint is held together by a blocking ring 8, screwed or welded into the socket and bearing via insulating spacer 7 on the rear face of the flange 4. The spaces 22, 23 are filled with a hardenable resin and any gas bubbles trapped therein or formed during curing are held at 24. The space 14 may be filled with non-hardening jelly-like material which is inert to the fluid within the pipes and which is non-adhesive. The interior insulating linings 15, 16 of the pipes meet at join 17 so that cracking of the linings does not occur when the joint is stressed. Any seepage through the linings therefore occurs at 17 and is prevented from penetrating the join by the overlap of rings 5 and 6. Further, the retention of ring 6 against radial spread by wall 11 prevents mechanical disruption of the linings 15, 16. The bottom of the socket and the end face of flange 4 may be annularly grooved, and electrodes 18, 19 of inert material, (e.g. platinumplated titanium) may be placed in the walls of the pipes approximately one pipe diameter from the ends of the linings 15, 16 so as to prevent corrosion when electroconductive liquids flow through the pipes. In a further embodiment (Fig. 3, not shown) the ring 7 is replaced by a smaller ring (51) bonded in a recess (91) in the rear surface of the flange 4. The outer diameter of the recess is smaller than the outer diameter of the flange and the ring and flange are partly overlapped by an elastic sealing ring (61) held in an external rebate in the forward end face of plug 8.