Casting pipe for continuous casting of steel - with refractory coating resisting erosion by molten casting powder, so pipe has long working life

摘要

The pipe is located on the bottom of a tundish, so the bottom end of the pipe enters the molten steel in the mould. The pipe is made of a refractory mixt. of alumina and graphite, and possesses an integral layer of refractory on the peripheral zone of the pipe which comes into content with molten casting powder floating on the surface of the molten steel in the mould. Layer has excellent erosion resistance w.r.t. the molten casting powder, and contains by wt. 2-10% carbon, 70-90% ZrO2, 5-27% silicon carbide and or amorphous silica, and max. 3% of accidental impurities. The refractory layer is designed to provide the casting pipe with long working life. Layer prevents the molten layer of casting powder from attacking the pipe, so the latter will withstand the casting of molten steel contained in more than five ladles and fed through the tundish into the mould each ladle contains e.g. 250t steel.