GB191216165A - A Method of Uniting the Ends of Rails, Girders and other Parts of Iron and Steel Structures. - Google Patents

Abstract

16,165. Goldschmidt Akt. - Ges., T. July 28, 1911, [Convention date]. Soldering; welding; thermo-aluminic processes.-The ends of rails, girders, or other iron and steel structures are united by a layer of carbon-free metal such as copper, silver, nickel, or alloys thereof, such as bronze or of copper-plated or nickel-plated iron sheets instead of ordinary sheet metal, as described in Specification 18,328/99, the work and intermediate layer being heated, and the work being immovably fixed so that the pressure to effect the weld is produced by the expansion of the work. The welding may be effected by the alumino-thermic process in which aluminium or calcium-silicon, silicon-magnesium, aluminiumcalcium, &c. may be used, or by the use of hot gases blown through a mould surrounding the joint, or by electric heaters of the resistance type. The alumino-thermic processes may be carried out in either of two known manners. In one process the resulting molten slag and iron is poured over the rim of the crucible into the mould so as to obtain a thin layer of slag on the work and thus prevent the molten iron from coming into contact with the work and thus to obtain a uniform union over the whole cross-sectional area. In the second process, molten metal is run out of the bottom of the crucible into the lower part of the mould to form a fusion weld at the foot of the rail, the intermediate metal being inserted only between the head and web portions, and being heated by the slag. The ends of the rails are mechanically cleaned and evenly dressed before inserting the intermediate metal so as to ensure a good contact. The parts may be butt-welded or lap-welded, the parts having bevelled ends or being provided with male and female joints, or with scarf joints, for example where half the thickness of each is removed ; in this latter case the longitudinal faces may also be joined.