BLAST FURNACE TUYERE WITH PROTECTIVE COATING Russian patent published in 2006 - IPC C21B7/16 

FIELD: ferrous metallurgy, namely structures of blast tuyeres for blast furnaces.

SUBSTANCE: tuyere includes inner and outer copper sleeves mutually joined on their ends by means of flange and mouth part. Three-layer protective coating is applied onto outer working surface. Such coating is deposited by means of plasma spraying of material; it includes first and second metallic layers and also third layer containing zirconium dioxide. Protective coating is applied onto the whole outer copper surface and onto end portion of inner surface at side of its mouth part. First layer of protective coating is made of molybdenum, second layer is made of nickel base refractory alloy and third layer is made of aluminum compounds and zirconium dioxide. Each layer of protective coating has thickness 0.3 - 1.5 mm. Wire is used as material for applying each layer of coating.

EFFECT: enhanced strength, increased useful life period of tuyere.

3 cl, 1 tbl, 6 ex