| 摘要 |
Dry spraying substance for coating walls of metallurgical ovens is prepared by the dry mixing of from 60 to 85%, and preferably 70% of a raw material consisting of chromium magnesite, chromium ore, magnesite, phosterite, mullite, sintered magnesite, dolomite and the like, or a mixture of two or more of these raw materials, for basic coatings, or alternatively from 60 to 85% but preferably 70% of a raw material such as zirconium, silicon carbide, silicon dioxide and the like, or a mixture of two or more of these raw materials, for acid coatings, with from 10 to 30%, but preferably 20% of a first binding agent, such as a synthetic resin, polyethylene, polyester, sodium silicate (dry) bitumen, tar, asphalt, bituminous, tar-like residues and the like, and with from 5 to 15%, but pref. 9%, of a second binding agent, such as binding clays, magnesium sulphate, kaoline, bentonite, melasse (dry) adn the like, with pref. 1% of a flowing agent, such as calcium hydroxide, glass flour, aluminium oxide, silicic acid, sodium silicofluoride, titanic acid, sodium sulphate, boric acid and the like. This preparation eliminates the disadvantages of liquid or moistened coatings, the application of which is laborious and often requires long shut down periods of the oven or the use of special equipment. |
