Blast furnace tuyere with calorized working surfaces - which permit higher wind temp. and reduce coke consumption

摘要

The bore and outside surface of the tuyere are coated by calorizing and the inside surfaces of the cooling jacket may also be calorized if required. The coatings are pref. obtd. by the diffusion of a mixt. of Al and active Al2O3 at 800 degrees C, to form a coating of 0.5-5 mm on the inner and outer surfaces of the tuyere, and 0.1-1 mm on the inside surfaces of the cooling jacket. Prevents the deposition of molten metal and/or slag on the surface of the tuyere and also the erosion of the cooling jacket due to the high velocity of the cooling water. The result is an increase in the working life of the tuyere.