GB457080A - Improvements in the manufacture of metal tubing - Google Patents

Abstract

457,080. Making metal tubing. HEILBUT, M. H., Kennan's House, Crown Court, Cheapside, London.-(Bundy Tubing Co. ; 4815, Bellevue Avenue, Detroit, Michigan, U.S.A.) Dec. 11, 1935, No. 34310. [Classes 83 (ii) and 83 (iv)] Angular bending.-Multiple-ply metal tubing is made from strip stock by rolling up one edge, bending the strip axially reversely to the direction of rolling this edge, and rolling up the opposite edge of said strip prior to enclosing this latter rolled up edge within the first rolled up edge. The strip stock 1 drawn from a supply reel 2, Fig. 2, passes between preliminary rolls 3, 4 and 5, 6 and then to sets of rolls with three rollers in each set, three of the rollers 12 being arranged on axes at right angles to those of the corresponding pairs 10, the strip here takes the double-bent shape, Fig. 5, with a radius at A, a reverse bend, and a radius at C. The radius at A is held in the subsequent rolling operations while the radius C is bent around to form a complete enclosure, Fig. 11, when it reaches the rolls 18, 20, and this operation is continued to produce an overlapping portion when the rolls 29 are reached, Fig. 15. Finally the radius A is bent about the point B, Fig. 17, to enclose the overlapping portion already formed and thus to complete a self-sustaining multiple-ply tube, Fig. 23. Rolls such as 5, 6, 16, 17, 25, 26 may be driving rolls while the smaller rolls may be idlers. Strip provided with a coating of copper or other metal may be used and after formation into tube form may be passed through a furnace to melt the copper and seal the tube.