Electrode seal for use in a metallurgical furnace

Abstract

An electrode seal for use in a metallurgical furnace, the furnace comprising a furnace space heated by electrodes extending through an aperture into the furnace space. The electrode seal comprises at least three sets of shoes in consecutive lateral contact, each shoe having a biasing member for biasing a surface of the shoe toward one of the electrodes thereby allowing the one electrode to longitudinally move within the electrode seal while providing electrical insulation between the electrode and the aperture.

What is claimed is: 
     
         1 . An electrode seal for use in a metallurgical furnace, the furnace comprising a furnace space heated by electrodes extending through an aperture into the furnace space, the seal comprising:
 at least three sets of shoes in consecutive lateral contact, each shoe having a biasing member for biasing a surface of the shoe toward one of the electrodes thereby allowing the one electrode to longitudinally move within the electrode seal while providing electrical insulation between the electrode and the aperture.   
     
     
         2 . The electrode seal of  claim 1 , wherein the at least three sets of shoes provide a gap around the electrode to allow for a free lateral movement of that electrode. 
     
     
         3 . The electrode seal of  claim 1 , wherein the at least three sets of shoes allow for a lateral movement of the one electrode therewithin while maintain the electrical insulation. 
     
     
         4 . The electrode seal of  claim 1 , wherein the at least three sets of shoes comprise a first layer of ceramic inner shoes and a second layer of copper outer shoes, the two layers of shoes forming a circle and an inner diameter of the circle being greater than the electrode thereby providing a gap therebetween. 
     
     
         5 . The electrode seal of  claim 1 , wherein the at least three sets of shoes are drilled through evenly distributed holes from outside to inside. 
     
     
         6 . The electrode seal of  claim 1 , wherein the biasing member is a spring. 
     
     
         7 . The electrode seal of  claim 1 , wherein the biasing member is adjustable to provide greater or less bias with one end pressed upon the cooper shoe and the other end against an adjustable bronze screw. 
     
     
         8 . The electrode seal of  claim 1 , wherein the biasing member is replaceable. 
     
     
         9 . The electrode seal of  claim 1 , wherein the biasing member is electrically insulated on both ends with plastic discs against copper shoe on one end and against the copper screw on the other. 
     
     
         10 . The electrode seal of  claim 1 , further comprising electrical insulating material packed around the electrode above the at least three sets of shoes, the material providing gas seal confined and pressed by a threaded copper cap which is tightened with a threaded copper ring welded on another copper cap beneath it as a chamber surrounding the shoes. 
     
     
         11 . The electrode seal of  claim 10 , wherein the electrical insulating material is high-temperature resistant ceramic fiber material. 
     
     
         12 . The electrode seal of  claim 1 , further comprising a chamber surrounding the shoes for containing pressurized electrically inert gas, the electrically inert gas for providing a pressurized seal for preventing gas escape from the furnace space, wherein the pressurized gas penetrates through the holes in the shoes and is distributed around the electrode evenly to push down along the electrode to prevent the furnace gas and dusts from within the furnace space flowing through the gap around the electrode thereby preventing at least some of the gas from leaking and preventing at least some substance attached to the electrode from hindering vertical movement of the electrode. 
     
     
         13 . The electrode seal of  claim 1 , further comprising an electrically insulated cooling member surrounding an electrode. 
     
     
         14 . The electrode seal of  claim 13 , wherein the cooling member comprises a cast copper plate. 
     
     
         15 . The electrode seal of  claim 14 , wherein the cast copper plate is protected from underneath by a durable insulating material. 
     
     
         16 . The electrode seal of  claim 14 , wherein the insulating material is a castable material. 
     
     
         17 . The electrode seal of  claim 15 , wherein the castable material is a high alumina castable. 
     
     
         18 . The electrode seal of  claim 14 , wherein the cast copper plate defines a contiguous inner channel for directing cooling fluid flowing therethrough. 
     
     
         19 . The electrode seal of  claim 13 , wherein the cooling member comprises a copper plate. 
     
     
         20 . The electrode seal of  claim 12 , wherein the chamber is at least partly defined by the cooling member.