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The start-up of the new Danieli micromill at CMC Steel, Arizona marks the beginning of a new era in production of commercial steel long products. With a direct link between caster and mill, the line can convert scrap to rebar in less than two hours with a saving of $40-50 per ton.
JUST 13 months after construction above foundations started the first heat was poured at the new Danieli micromill (MI.DA®) at Commercial Metals Co (CMC) Steel Arizona in Mesa, near Pheonix Arizona. The new steel complex, first of its kind worldwide, is based on the regional-mill product-focused concept developed to serve a local market focusing on a specific product range and using local scrap.
Project Genesis
Since their origin, minimills have been growing in size to capture economies of scale. Now, they have reached capacities exceeding IMt/y. However, markets that can serve these volumes are being exhausted. From the early 1970s, CMC had a vision of a highly efficient, lowinvestment, minimal manning, low-operating cost minimill that can serve specific geographic areas with a good balance of scrap supply and a market for the finished product.
Over the years, CMC's management had challenged its own people and Danieli to come up with the right idea to fulfil this vision. In mid 2004 Danieli approached CMC with a design concept that eventually led to the construction of the mill in Arizona. The design capitalises on CMC's management and motivational philosophies, and employs Danieli's Endless Casting Rolling (ECR®) process where melting, casting and rolling are carried out in one continuous and uninterrupted production process from scrap to finished product. This eliminates the need for a conventional reheating furnace along with all associated entry/exit equipment, auxiliaries and warehouse. This results in significant savings in the initial investment, utility consumptions and operating costs. The design also includes the 'Direct Rolling & Bundling system' (DRB®), which allows cutting to final commercial length directly off the final finishing stand. The result is a very compact arrangement of the whole cooling bed/bundle forming and tying station, with significant savings in the initial investment and production costs. The mill also features a Quenching and Tempering system for Bar (QTB) that enables the production of low-cost billets in the meltshop, by using fewer...