摘要 |
Provided is a bimetallic tube for transport of hydrocarbon feedstocks in refinery process furnaces, and more particularly in furnace radiant coils, including: i) an outer tube layer being formed from carbon steels or low chromium steels comprising less than 15.0 wt. % Cr based on the total weight of the steel; ii) an inner tube layer being formed from an alumina forming bulk alloy including 5.0 to 10.0 wt. % of Al, 20.0 wt. % to 25.0 wt. % Cr, less than 0.4 wt. % Si, and at least 35.0 wt. % Fe with the balance being Ni, wherein the inner tube layer is formed plasma powder welding the alumina forming bulk alloy on the inner surface of the outer tube layer; and iii) an oxide layer formed on the surface of the inner tube layer, wherein the oxide layer is substantially comprised of alumina, chromia, silica, mullite, spinels, or mixtures thereof.
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