求翻译：设置在重力除尘器上部圆筒形管道内，是一盘式阀。高炉正常生产时处于常通状态，高炉休风时用来切断高炉炉顶与除尘器之间的管路联系。是什么意思？

Set within a cylindrical pipe in the upper part of the gravity precipitator, is a disc valve. Blast furnace in the regular state normal production, blast furnace off when the wind is used to cut off the pipeline links between the top of blast furnace dust catcher.