Welding of steels of different compsn. - facilitated by deposition of intermediate layer of ferritic steel (OE 15.2.78)

摘要

The rails of a railway junction are bolted to distance pieces which are welded to the centre piece or frog. Since the distance pieces are usually made from a low C steel and the frog is made of a heat treated alloy steel it is not possible to weld the two materials directly to each other. To overcome this problem an electrode of ferritic steel having an equivalent carbon content of 0.20% is used to deposit a layer of weld metal on the surface of the frog. The frog is then welded to the distance pieces with the weld fillets. The equivalent C content is calculated from the amt. of other elements present such as Mn, Cr, Ni etc.