Patent GB-432454-A (GB)
Title: Process and apparatus for lining metal pipes with bitumen or bituminous compositions
IPC: B05D7/22
Filed: 1934-04-16
Abstract: 432,454. Lining pipes with bituminous material in centrifugal machines. PIPE LININGS (AUSTRALASIA), Ltd., 341, George Street, Sydney, Australia. April 16, 1934, No. 11439. Convention date, April 24, 1933. [Class 87 (ii)] A process of lining metal pipes with bituminous material, comprises the introduction in a distributed form of small solid pieces of bitumen into the interior, capping the pipe ends to retain the material therein, fitting the charged pipe with detachable wheels or runners so that it can roll through a heating oven with controlled entrance and exit gates, and thereafter roll on to the supporting rollers of a centrifugal spinning - machine so that it is still supported during rotation on the wheels or runners, and finally cooling and removing it from the spinning- machine prior to the removal of the wheels or runners. Fig. 1 shows the general lay-out of the apparatus comprising a brick-lined oven 10 floored with steel plates and suitably maintained at about 400‹ F., for example by a gas-furnace 15, the rolling pipes being delivered thereto, one at a time through the air-lock double-doors 18- 19 operated by the capstan 20. The sloping floor of the oven is kept fully charged with pipes so that each is subjected to the necessary time-lag for attaining the temperature of the oven before being delivered in turn through similar air-lock double-delivery-doors 22, 23 operated by the capstan 24. From this point the pipes 45 roll down on to the rollers 30, 31 of the spinning machine and are locked in position by the lowering of the pivoted counterweighted toproller frame 40, operated by the capstan 42. The rollers 30, 31 are comparatively short in length and are mounted in sets on parallel shafts so that each pair registers with and supports one of the detachable wheels or runners applied to the pipes. One or more rollers on each shaft is double-flanged as shown at 60, to prevent axial movement of the pipe in either direction. The rollers are driven through chain reduction gear 34, 36 from a motor 35. After spinning, the pipe is removed by manipulating a lever 46 which first raises it from the rollers and arrests it in the recess 47 and afterwards allows it to run down on to a truck or runway. The wheels or runners may be formed in two halves bolted round the pipe as shown at 55, Fig. 4, or they may be formed as rings which slip over the ends of the pipe and hold the latter in a three-point support 50, 51, one of the points comprising a radiallyadjustable clamping screw 51. In a third construction, the rings are provided with guideways for wedges which are moved axially to clamp the ring on to the pipe or release it therefrom. The two outer runners may be combined with the end caps for the pipes. Reference is made to the necessity for maintaining the temperature round about but not exceeding 400‹ F. throughout the lining operation and to the selection of a suitable bituminous material, a selected air-blown bitumen loaded with 11 to 20 per cent of diatomaceous earth or like powdered filler being preferred. The tests which the material should pass, are set out in the Specification. The bitumen is fed into the pipes either through a funnel while the pipe is canted upwardly or by means of a turnover traversing spoon or trough.