Electric contact for molten metal, esp. in arc furnaces - where contact has enlarged rear portion contg. several chambers through which coolant is circulated

摘要

The electrode consists of two parts, viz. a front part (3) in contact with the molten metal, and a rear part (6) contg. a cooling circuit and possessing a much larger cross-section than part (3) so the surface for heat exchange with the coolant is increased. The internal cooling circuit pref. consists of an axial chamber surrounded by numerous peripheral chambers; and each chamber contains at least one pipe delivering the coolant. Part (6) of the electrode is pref. made of Cu, whereas the front part (3) is made of material with a high m.pt. e.g. steel. Instead of numerous peripheral chambers, one outer ring chamber may be used. Part (3) is pref. fitted with refractory rods or plates projecting into the molten metal to reduce turbulence at the melt/electrode interface. Used esp. as an electrode located in the hearth of an arc furnace using direct current, where the coolant is pref. liq. gas, e.g. carbon dioxide nitrogen or another liq.