Abstract
Electroslag remelting (ESR) process has widespread in the world as a process for making high quality steel.
Main furnace types of ESR are stationary mould, moving mould and ingot withdrawal type. In general, the stationary mould type has been applied to make small section ingots, and the other moving mould and ingot withdrawal type have been applied for large section ingots in recent years.
As a high quality tool steel, for instance, a high speed tool steel, requires homogeneous internal quality, especially fine carbide distribution, ESR ingot sections should have been small. By that reason, the stationary mould type has been applied. The stationary mould type process needs mould preparation, melting and ingot strip, and which consequently causes low productivity.
In order to obtain high productivity, high ingot yield, low operational cost and flexible ingot weight, a new perfect continuous melting ESR process for small section ingots has been developed in Shibukawa Plant, Daido Steel Co., Ltd.
This report presents the outline of the new continuous ESR process, some technical developments of controlling slag composition and of mould corrosion prevention and some operational results.
