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Batch AnnealingModernization at CaliforniaSteel Industries

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In the mid-1960s and early 1970s, as U.S.cold roll sheet producers were building 5- stand sheet cold reduction mills, manyadded batch annealing facilities in order to process the additional cold reduction throughput. Often these facilities consisted of a 4- stack-per-operating-base configu- ration, which led to handling and equipment efficiencies.With these units being in service30+ years, operators must now con- sider whether to continue to repair, replace in-kind or upgrade to newer technology. California Steel Industries (CSI) faced such choices in the late 1990s with its 1970s-vin- tage single-stack shop and an older 4-stack facility.CSI considered the upcomingrepair needs of the aging equip- ment and took the opportunity to gain operating, maintenance and spares efficiencies by consolidating to a modernized single shop. Through a careful evaluation of the advantages of 100% hydrogen atmosphere annealing, CSI decided to modernize all its annealing equipment in order to utilize this technology.Working with several potentialsuppliers, CSI developed a compact design strategy to place the project in the available space ahead of the temper mill. A single turnkey sup- plier was chosen to finalize the design, direct the construction and commission the equipment. All this activity was to take place in close proximity to operating areas yet betransparent to the flow of cold rolled sheet product to CSI customers.The project was successful in that it startedearly and was completed under budget. Numerous safety features for both hydrogenand natural gas were incorporated into the base, furnace and control systems. Stringent California NOx emission targets were met using the best available control technology. Savings of 50% or more in electricity and natural gas consumption were welcomed in a time of price and supply volatility in California utilities.

California SteelIndustries faced the choice of whether to repair, replace in- kind or upgrade the anneal shops to newer technology. Modernizing to a 100% hydrogen anneal shop was justified based on significantly reduced operating costs and the logisti- cal advantages of consolidating two shops into one. Background

Integrated mills began constructing the next generation of hot strip mills in the 1960s. These mills had more heating capacity, power and finishing capability than their predecessors. The resulting increased output made more bands available to cold rolled sheet products. Higher speed 5-stand cold mills and new annealing facilities, primarily 4-stack HN shops, followed.Capital expenditures were directed backtoward the primary end in the 1970s and early 1980s. BOF steelmaking was expanding, and continuous casting became a competitive necessity. Considerable sums were spent on related environmental issues and controls.After the 1960s and until the late 1980s, onlylimited batch annealing capacity was added to steel plants. Annealing in a 100% hydrogen inert atmosphere made its first significant domestic debut at an integrated plant at U. S. Steel’s Mon Valley Works at its Irvin Plant.

California Steel Industries

Kaiser Steel was built in 1942 to supply steel for West Coast shipbuilding and other mar- kets. The plant was strategically positioned in southern California during the war years, thus making raw materials and the markets it served highly accessible. However, Kaiser Steel was shuttered in the early 1980s.A 50/50 venture, under the nameCalifornia Steel Industries, soon followed between Companhia Vale do Rio Doce of Brazil and Kawasaki Steel of Japan. CSI Authors

David W. Johnson , Manager—Cold Sheet Mill and Roll Shop (left), and Harold E. Parker II , Manager—Engineering Department, CaliforniaSteel Industries, Inc., Fontana, Calif.; Michael W. McDonald , VicePresident, General Manager of Entec Div. (center), and Christopher G.Williams , Senior Design Engineer—Project Manager (right), Rad-Con,Inc., Cleveland, Ohio (mike.mcdonald@rad-con.com)
52 AISE Steel Technology November/December2002