GB928336A - Improvements relating to screw-tightened compression sealing glands for electrical cable - Google Patents

Abstract

928,336. Mechanical couplings for cables. A. REYROLLE & CO. Ltd. Dec. 3, 1959 [Dec. 4, 1958], No. 39199/58. Class 38 (1). A compression-sealed gland for an electric cable 14 comprises a base 10 screw-threaded at 15 for engagement by a locking sleeve 24 having a portion of reduced diameter which is fitted over the external polychloroprene cable sheath 28 surrounding the armour 20. The base 10 also includes a tapered tubular anvil 16 provided with light radial saw cuts 37 and a circumferential groove 40 which aids the constriction of the fingers defined between the saw cuts. An abutment shoulder 33 on the locking sleeve 24 engages against a brass or cadmiumplated steel clamping ring 34 of which the clamping surface 35 engages the outer layer of the double-layer wire armour 20; a separator pad 32 of brass or cadmium-plated steel may be inserted between the layers of the armour. A synthetic rubber sealing sleeve 41 fits closely around the inner sheath 19 of the cable, but when the sheath is of a conducting material such as lead the sleeve is also made of conducting material so that the sheath is earthed to the base 10. When the locking sleeve 24 is tightened up by rotation on the threaded portion 15 of the base, the clamping ring 34 forces the fingers of the anvil to yield inwardly and compresses the sleeve 41 on to the cable sheath 19. A fluid-tight seal is also formed against the outer cable sheath 28 by a resilient washer 30 acted on by a screwed cap 29. In a modification, Fig. 4, the splayed end 67 of the cable armour is folded over a clamping ring 58 having a double taper and is secured by wire binding 68 to a groove 69 formed in the ring 58. Additional saw cuts 66 are made in the outer flange 61 of the base 60. On screwing the locking sleeve 51 into position, the splayed armour is clamped at the inside and outside of the clamping ring 58 and the flange 61 is expanded and locked by friction with the sleeve 51 which is thus prevented from becoming unintentionally loosened.