This article introduces a new & practical welding slag cleaning unit for inside welding of helical submerged arc welding pipe,including facility structure,principle of welding slag cleaning and usage method.

In order to improve working condition, based on water granulated slag's looseness an automatic slag removal machine is developed to clean slag runner instead of manual work.

Analysis on origins of tailwater level increase and benefit of Liujiaxia hydropower station after tailrace debris removal;