METHOD FOR MONITORING MOLTEN METAL SURFACE IN DEGASSING REFINING

PURPOSE:To simply monitor a molten metal surface in a degassing refining and to decide the position of submerged tubes by inserting an image transmission means toward molten metal surface through gas between a molten metal vessel and a degassing vessel inserting the submerged tubes at the lower part thereof into the molten metal. CONSTITUTION:The lower part of the degassing vessel 10 is inserted in a ladle 2 and the inner part of the degassing vessel 10 is made to vacuum, and the degassing treatment is executed while circulating the molten steel 3 between the degassing vessel 10 and the ladle 2 through the submerged tubes 12. Then, the detecting part 20 is inserted from the gap between the ladle 2 and the degassing vessel 10 and a fiber scope 21 disposed on the tip part thereof, is set in the vicinity of the molten steel 3 surface. The molten steel surface is monitored with the detector 20 through the fiber scope 21 providing an objective lens 22 and reflecting mirror 23. By this method, the position between the molten steel surface and the submerged tubes 12 can be accurately decided.