GB823769A - Improvements relating to electrodes for glass melting furnaces - Google Patents

Abstract

823,769. Furnace electrodes. ELEMELT Ltd. Sept. 3, 1956 [Sept. 9, 1955], No. 25809/55. Class 39(3) An electrode for a furnace for melting or refining glass and other vitreous products comprises an internally water-cooled stem 13 of mild steel or other material not readily oxidizing in air carrying electrode plates 10 of molybdenum, tungsten, platinum or other material withstanding immersion in molten glass. The inner end 18 of the steel stem 13 is protected against molten glass by joining it e.g. by fusion to a socket 14 of molybdenum or tungsten carrying an electrode plate 11 to which the plates 10 are screwed. Current is led to the electrode by the stem 13 or by a copper or steel rod 15 extending axially through the stem and threaded at its end into a molybdenum stud 16 fitting tightly into holes in the socket 14 and plate 11. A steel or copper tube 19 provides annular waterways in the stem 13, the end 18 of which is formed with a sleeve-like part 17 fitting over the molybdenum stud 16 and sealed e.g. by fusion to the conductor rod 15 passing therethrough, so that the cooling water is in contact with steel only and not with molybdenum. The rod 15 may however be threaded into the sleeve 17. The molybdenum socket 14 is in good thermal contact with the end 18 of the stem 13 and with the electrode plate 11 so as to cool the latter. The main electrode body comprises molybdenum plates 10 screwed into the plate 11 which conducts heat therefrom to the stem. A molybdenum plate 23 is secured by bolts 25 and spacing members 28 to the centre part of the electrode 10 and is spaced therefrom so as to form a cooling space normally filled with glass or other insulation between the plate 23 and the centre of the plates 10 as described in Specification 756,382, which is referred to.