GB852864A - Improvements in or relating to the lining of pipes - Google Patents

Abstract

<PICT:0852864/III/1> A machine for applying a lining of inert, e.g. cementitious, material to a pipe through which it is progressed comprises a rotatable distributer head 13, a pipe 15 for feeding fluent lining material to the head, wheels 19, 20 for supporting the machine in the pipe and a trowel 22 driven by the wheels to rotate slowly and smooth the lining. The machine is drawn through the pipe in the direction 11 by a cable, not shown, while the head 13 is rotated at high speed by an electric motor 14. The head 13, motor 14 and wheels 19, 20 are supported by the pipe 15 which is cranked at its forward end to accommodate bevel gearing 32, 36 which rotates a hollow shaft 21 as a result of a chain drive 31 from the axle 24 of the front pair of wheels 19. An axially movable rod 23 for controlling the radial extension of the trowel members is slidable in the shaft 21, which is surrounded by a stationary sleeve 37 which provides end bearings for the shaft and end seals against the escape of cement mortar. The distributer head 13 comprises end members 41, 42 between which radial plates 44 are clamped to form slots 45 and a sealing ring 39 and ball race 40 are located between the member 41 and sleeve 37. As the machine is drawn through the pipe, lining material flows through the conduit 15 and, passing through an annular channel 46 between the pipe and the sleeve 37, is thrown out, through the slots 44, as the head 13 is rapidly rotated by the motor 14 which drives it through a tubular shaft 43. The position of the wheels 19, 20 to suit pipes of different diameters may be adjusted by altering the thickness of a spacer behind the carrier 47 on which the axles 24, 25 are mounted. An agitator may be provided at the rear end of the tube 15. To increase the bearing friction of the wheels 19, 20 on the pipe, spring-loaded overhead wheels may engage the top of the pipe interior.