Cast iron continued scaling

The largest use for calcium carbide is in the production of acetylene for oxyacetylene welding and cutting. Companies producing compressed acetylene gas are located neat user plants to minimize freight costs on the gas cylinders. Some acetylene from carbide continues to compete with acetylene from petrochemical sources on a small scale. In Canada and other countries the production of calcium cyanamide from calcium carbide continues. More recentiy calcium carbide has found increased use as a desulfurizing reagent of blast-furnace metal for the production of steel and low sulfur nodular cast iron. 

On an industrial scale, diazotization reactions are chiefly carried out in cast iron kettles that are lined with brick or rubber as a protection against acid. Wooden vats also continue to be used. 

Minimum impact energies to initiate the explosion of various exothermic mixtures, used for the continuous casting of steel, were determined. Components used included sodium nitrate, aluminium-iron scale, silicocalcium, ferrosilicon fluorspar, borax, etc. Hazardous mixtures were defined, and improved safety controls were derived. 

Chilled iron shot or grit can be used for the removal of rust, mill scale, heat treatment scale, and old paint from forged, cast, and rolled steel. This abrasive breaks down gradually against steel substrates, so continual sieving to retain only the large particle sizes may be needed if a rough surface profile is desired in the cleaned surface. 

The mill scale utilized in this study is formed in a continuous casting plant and is of non-oily nature. Other than iron oxides of different valence states, it contains metallic iron and impurities. Table I displays the chemical analysis of the mill scale. In the SHS experiments, a mixture of Mill-scale, NiO, Cr203, M0O3 and A1 powders were used in order to produce metallic Fe, Fe-Ni, Fe-Ni-Cr, and Fe-Mo alloys. The metal oxide powders have over 96 % purity and 200 pm average grain sizes. The advanced thermochemical simulations of the reactions were... 

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