GB1243613A - Improvements in or relating to machines for internally sealing pipe joints or flaws - Google Patents

Abstract

1243613 Repairing pipes TATE PIPE LINING PROCESSES Ltd 22 July 1970 [8 Aug 1969] 39808/69 Headings F2N N1A1 N1A3 N1A5 and N1A6C A machine for internally sealing pipe joints or flaws comprises a prime mover 16 for rotating an air-operated sealant applicator 76 and operating a pump 63 delivering sealant from a container 17 to the applicator, all the parts containing a passage for the air supply to the applicator. The machine is moved along a pipe until an electro-magnetic detector 11, comprising two coil-surrounded metal cores 32 connected to a supply voltage and an indicator and supported by a skid 21, locates a flow or joint; the machine is then moved along the pipe until the joint is level with an air blower 13, driven by an electric motor 37 and supplied with compressed air via a pipe 22, the air being emitted through a slot, circumferential and inclined to the radial plane, and a rotary cleaning device 14, comprising two radial arms 46 with spring-loaded wire brushes 47 or metal strips with abrasive pads and counterweights affixed. After the joint has been cleaned, primer from a tank 12 is injected into the blower air supply, via a control switch 44, and sprayed on to the joint. The machine is moved further along the pipe to align the sealant applicator 76 with the joint, where a clock or timer operates an air supply to activate a locking pin, to hold the machine in position, a piston in the sealant container 17, to surcharge the pump 63 with sealant, and a piston which acts on a pivoted arm 77 to extend the applicator 76 against a spring 78A; after a period, the timer switches in another clock or timer which maintains the air pressure and switches on the electricity supply to the prime mover 16 which rotates the pump 63 and the applicator via a shaft through the sealant container 17. After a period, the second timer switches in a third clock or timer which cuts off the air supply so that the applicator is gradually retracted whilst rotating, and then the electricity supply is cut off. The air-operated piston acting on the applicator is held in an end cap which rotates with the applicator; the sealant supply to the applicator is via flexible hoses 75. The machine movement in the pipe is aided by skids 21 and/or sets of rollers 20.