| 摘要 |
<p>A duct for an electric furnace is provided to enhance endurance life the welds by removing weak welds directly coming in contact with a path through which gas with a high temperature passes in a duct with structure of a water cooled double pipe. A duct for an electric furnace comprises: an outer tube(3) having connecting flanges(1) formed on both ends thereof and pipes(2) installed on both end sides thereof; an inner tube(4) inserted into the outer tube to form a space part between the inner and outer tubes; a spiral plate(5) spirally installed in the space part between the inner and outer tubes to form a pipeline through which cooling water flows; and inner tube end flanges(6) installed on both ends of the inner and outer tubes to seal the space part through which cooling water flows, wherein the inner tube end flanges are formed by bending both ends of the inner tube to the outer side, and the inner tube end flanges are integrally formed by welds(7) of which end portions are welded to edges of end portions of the outer tube. The inner tube has bending grooves formed on inner portions thereof on which the inner tube end flanges are bent so as to bend the inner tube end flanges easily.</p> |
