八钢冷轧罩式炉内罩返修工艺

The Technique of Repairing the Inner Cover of Bell-Shaped Cooling Rolling Furnace in Bagang

八钢冷轧罩式炉内罩已使用10年,经检测内罩下部燃烧区已达使用极限小于4 mm,上部完好大于5 mm (内罩壁厚6 mm,小于3.5 mm报废),采用更换内罩下部与上部焊接的方法,制定了内罩下部制作方案、内罩下部与上部焊接工艺及检测方法,返修后内罩经使用后取得了良好效果。

The inner cover of the cooling rolling bell type furnace in Bagang has been used for 10 years. After inspection, the lower part of the inner cover for combustion has reached the limitation of its life span, the thickness of which is less than 4 mm. But the thickness of the upper part of the inner cover still remains more than 5 mm (the standard thickness of the inner cover is 6 mm. If the thickness of the inner cover is less than 3.5 mm, the inner cover should not be used). The repairing method is to replace the old lower part with a new one and to weld the new one with the original upper cover. The new method is proved to be effective in practice.