Large ESR forging ingots and their quality in production

ESR is known as an alternative step on the continuous improvement in single ingot production for heavy forgings. In the recent past a new state of the art ESR remelting system was installed with the possibility to produce ingots in diameter from 1000mm for 45tons till 2000mm for 145tons. Consumable electrodes from traditional fabrication processes which consist of melting with electrical arc furnace, refining, degassing of the steel and bottom pouring will be used to produce one single heavy ingot with best cleanness with the help of electrode exchange technique. This paper tells about the furnace characteristics and the efforts to be made to ensure high quality level in material and furnace preparation as well as save automatic production performances during remelting and electrode exchange. Finally the results of ingots characterized by an elevated level of chemical homogeneity and internal quality such as to ensure the absence of defect greater than 0.5mm AVG during the final inspection of the forged part from the ESR production will be presented. The ESR process serves for the reproducible quality in heavy ingot making and tightens the limits in specifications together with high material yield.