Surface cleaning metals, esp. large workpieces - which are partly immersed in molten slag so surface skin can be removed by electroslag remelting

摘要

A molten bath of slag is formed in a vessel, and the bottom end of the workpiece is immersed in the bath, but only to a depth corresp. with the depth(t) of the surface layer which is to be removed from the bottom end of the workpiece. Electroslag remelting is then used to remove the surface layer to depth(t). The workpiece is pref. lowered gradually into the molten slag until the required depth has been removed. One pref. plant consists of a furnace or mould connected to one pole of an electric power supply, the second pole of the latter being connected to the workpiece so the surface of the latter melts. The molten metal thus obtd. may be drawn out of the bottom of the furnace in a manner similar to conventional electroslag melting. Very large components can be provided with smooth, clean surfaces free from cracks or fissures without the loss of a large amt. of metal; and the unsound hot tops of very large ingots may be completely removed.