Retrofits in camera of the oven Siemens Martin elementary retrofits in camera of the oven Siemens Martin elementary and in operation of the same, and operation of the same

摘要

1410045 Open hearth furnaces SIDNEY STEEL CORP 6 Nov 1972 [22 March 1972] 51019/72 Heading F4B A basic open hearth furnace for the production of steel has banks of tuyeres extending through the magnesite back wall 4 on each side of the taphole, each tuyere comprising an inner tube 13 and a coaxial outer tube 14 cemented into tar impregnated high density magnesite brick interlocked by recesses and protuberances, oxygen being supplied to tube 13 by valve controlled line 13a and a hydrocarbon, e.g. propane to the space between the tubes by valve controlled line 14a. The tuyeres are assembled side by side to form the banks (Fig. 5). The furnace is reversibly heated by end oil burners 8 associated with conventional air heating regenerators (9, Figs. 1 and 3). In operation lime, limestone, ore and scrap (up to about 60% by weight) are charged into the furnace, and heated by burners 8 and the tuyeres. Finally molten iron to complete the charge is added, burners 8 cut off and the oxygen/propane flow increased, the proportion of propane being about 3¢% by volume. The oxygen supply through the tuyeres may be out off after refining or after tapping and replaced by argon or nitrogen.