GB913029A - Low frequency induction furnace of the melting channel type - Google Patents

Abstract

913,029. Electric induction furnaces. ALLMANNA SVENSKA ELEKTRISKA A.B. May 18, 1961 [May 21, 1960], No. 18109/61. Class 39 (3). A low frequency induction furnace of the melting channel type comprises at least one exchangeable inductor unit 1, the lining of the furnace body, at least at the joint between the furnace body and the inductor unit comprising an inner sintered layer 8 of heat resistant ceramic material and an outer layer 9, preferably of the same material, in a powdered or other condition which has no tendency to crack, while the lining of the inductor unit is of normal heat resistant ceramic material, the outer layer of the furnace body lining being reinforced at the contact 'face with each inductor unit by means of a ring- shaped plate 12 supporting a substantially axially extending cooling channel 13, preferably of rectangular cross-section, engaging the outer layer of lining material, and the casing 6 embracing the lining 5 of the inductor unit being provided with ring-shaped cooling channels 20, the channel nearest the joint being adapted to concentrate the cooling effect towards the joint. The cooling channel 13 is preferably conical in shape to concentrate the cooling effect to the joint and draining channels 16, 19 may be provided to collect condensation and leakages from the coding channels 13, 20 respectively. A layer 17, e.g. chrome spinel, may be provided to prevent the linings of the furnace body and of the inductor unit from sintering together, and the casing 6 of the inductor unit may be provided with a gap of electrically insulating material 23 to prevent the formation of a shortcircuited secondary loop.