GB191308490A - A Process for Casting Ingots or other Castings. - Google Patents

Abstract

8490. Melaun, F. April 10. Casting processes; moulds.-In casting compound ingots, the metal is cast in successive layers after each preceding layer has solidified up to a certain height, thus increasing the opportunity for bubbles &c. to rise to the surface. The ingots may be employed in the manufacture of rails, bars, plates, sheets, &c. As applied to the casting of a compound ingot of hard steel and soft iron, the steel is first poured, and then the iron in such manner that the layers are uoited by an intermediate layer in which the steel and iron are intimately mixed. If the iron is introduced rapidly, it displaces steel from the centre and causes a trough-like junction between the layers. The mould is preferably an iron chill open at the ends and placed on an iron baseplate. The lower portion is made as thick as possible and may be cooled from the interior. The wall of the mould at the upper portion is of less thickness and is of such a nature that heat is carried off only very slowly. Specification 2216/73, which describes the casting of a compound ingot of copper and brass with an intermediate zone in which the metals are mixed, is referred to. According to the Provisional Specification, if the upper part of the metal first poured should cool down so far that a crust is formed, an electric arc or alumino-thermic mixture is employed to melt it again. Further, to prevent the trough-like junction becoming too marked, an intermediate inlet pipe may be provided between the ladle and the surface of the first-poured metal. Such a pipe may be fitted either on the ladle or the upper edge of the mould and may be bent laterally at its lower part. Also, the process is stated to be applicable to copper, tin, lead, and platinum.