In high-iron-tonnage operations, the cupola remains the most efficient source of continuous high volumes of iron needed to satisfy high production foundries or the multiple casting machines of centrifugal pipe producers. This article explores successful improvement technologies in cupola equipment, including preheated air blast, recuperative hot blast systems, and duplex electric holders. It discusses the shell, intermittent or continuous tapping, tuyere and blower systems, refractory lining, water-cooled cupolas, emission-control systems, and storage and handling of the charge materials. The article provides a discussion on the control tests for cupola, including the chill test and mechanical test. It concludes with information on specialized cupolas such as the cokeless cupola and the plasma-fired cupola.

Various types of furnaces have been used for cast iron melting. In terms of tonnage, the primary melting methods used by iron casting facilities are cupola and induction furnaces. This article describes the operation and control principles of cupola furnace. It discusses the advantages of specialized cupolas such as cokeless cupola and plasma-fired cupola. Melting in iron foundries is a major application of induction furnaces. The article describes the operations of two induction furnaces: the channel induction furnace and the induction crucible furnace. It explains the teapot principle of pressure-actuated pouring furnaces and provides information on the effect of pouring magnesium-treated melts.