Control upgrade of Inland No. 7 blast furnace using distributed open architecture

Distributed open architecture systems provide significant potential benefits in the application of process control automation in the iron and steel industry. For these reasons, Inland Steel selected an open architecture system for controlling the No. 7 blast furnace. The new system replaces an existing control system commissioned in 1980. It offers four major advantages compared with a closed system: (1) Cost savings of 30 to 50% on hardware and software. (2) Improved operating efficiency -- The wide band-width and high memory capacity permits the production of hot metal with fewer interruptions to the process. (3) Reliability -- The system offers a tenfold overall improvement in MTBF compared with the current on-line system. Moreover, redundant, continually operating control computers, G 2[sup VME] nodes (with reflective memory), and high security multiplexor I/O on all critical areas insure non-stop operation of process-critical functions during occasional malfunctions, thereby avoiding costly blast furnace shutdown. (4) Protection of blast furnace components -- By enabling the cost-effective monitoring of a large number of temperature points throughout the furnace hearth, for example, the system could extend the 7 to 12-year life expectancy of the furnace lining by two to three years. Configuration of a new, open architecture blastmore » furnace control system installed in place of a 10-year old single vendor system is described.« less