Metal Melting, Alloying and Casting in Practice

Abstract

Melting. Steel castings and ingots for working are generally cast directly from the refining furnace in which the steel is made. In certain cases there may be a separate melting and alloying stage. In the cast iron foundry, the pigs cast at the blast furnace are remelted and any extra alloying carried out. Pure copper ingots for working are cast directly from the refining furnace. With copper for castings and other non-ferrous metals, usually the refined metal is cast into notched bar ingots (Fig. 253) or sometimes slabs, of suitable sizes. These ingots are remelted, alloyed as required and cast into final shapes or ingots for working. Clean scrap of known composition is often incorporated at the melting stage. The various procedures are due partly to metallurgical factors and partly to the structure of the industry.