GB219742A - Improvements in methods of and apparatus for forging manifolds on pipes - Google Patents

Abstract

219,742. Marine & Locomotive Superheaters, Ltd., (Superheater Co.). May 1, 1923. Steam generators.-In converting the ends of a number of pipes to form a common junction piece, three or more pipes are held at the corners of a polygon, the ends are then slit longitudinally and the parts adjacent the' slits are then pressed outwardly until' they lie in the sides of the polygon or parallel thereto, where they are welded or forged together. A two-part die 9, Fig. 3, formed in part with' grooves 22, 23, 24, 25 separated by walls 26, 27 and in part with a square recess bounded by lines tangential to the grooves, receives an insert provided with grooves 12, 13, 14, 15 and walls 16, 17, which is inserted in the grooved portion of the die and held in place by tongues 18, 19 engaging recesses 20, 21 in the die. The punch is formed with four projecting legs 30, 31, 32, 33, Fig. 5, which merge into the body 29 in a curve, and may be formed along the lines 34, 35, 36, 37 into cutting edges. The pipes are heated, preferably while held in the relative positions they are to occupy in the finished product, and are then placed in the dies, and the punch pushed forward to slit longitudinally the walls of the pipes situated in the recessed portion of the dies and bend them outwards where they are welded together against the walls of the dies and against the ends of the walls 16, 17, 26, 27. The junction-piece mav be converted from square to circular form and rolled or pressed into a tube sheet of a boiler, feed water heater, &c. The end of the junction-piece may be rounded during formation by using a die and punch the recessed portion of the die, Fig. 19, and the body of the punch of which merge gradually from square to cylindrical shape at 40. In another form the insert may be formed with a square tapered extension 53, Fig. 10, and the punch formed with a corresponding cavity 54, Fig. 14, and with cutting edges 34<a>, 34b, 35<a>, 35<b>, 36<a>, 36<b>, 37a, 37b to sever each pipe along two lines, one portion of each pipe being bent inwards and the other outwards so as to form a junction-piece with a central hollow extension 41, Fig. 15. The taper of the part' 53 may be made abrupt enough to close the opening 50. The extension 41 may be closed down at its tip and the square jucntion-piece joined to another tube, or rounded as previously described, or the inner and outer square tubes may be drawn together to a common point. In joining the ends of three pipes a three-part die 9<a>, Fig. 18, may be used with an insert 11<a>, the pipes being slit along lines 57, 58, 59 and in joining five pipes the die and insert are as shown in Fig. 25, the pipes being slit at 60 - - 64. Specification 6304/15, [Class 83 (iv), Metals, Working], is referred to. Reference has been directed by the Comptroller to Specification 212,645, [Class 99 (i), Pipes and tubes, Joints, &c. for].