Continuous casting of metals - vacuum or controlled - atmosphere for large workpieces

摘要

In metals or other materials requiring good degassing or which when hot react easily with the atmosphere are cast in appts. comprising (a) a source of molten metal (b) an interchangeable ingot mould with water circulation and a molten metal level detector and (c) a dynamic air lock formed by aspiration chambers held at reduced pressures and separated by diaphragms and/or showers situated outside the vacuum chamber. Improvement consists of holding the air lock pressure constant by adjusting the molten metal level in the ingot mould as detected so as to maintain the difference between the section of the cast product and the diaphragms and esp. each aspiration chamber has ingot gripping wheels or rollers with cooling and centering means. This allows the appts. to be used for workpieces of large dimensions.