MILL TECHNOLOGY
STEELMAKING
The competitive substitute of conventional minimills It all began in the early 2000s in the USA, when a minimill customer asked Danieli to design an innovative mill to compete with the country’s big steelmakers in terms of operating costs and overall investment. The development of the Danieli MicromillMI.DA-technology followed from the successful application of the endless casting and rolling technology to the production of spooled coils and wire rod, rebars and smooth rounds.
MI.DA. size evolution from a single, 300,000-tpy co-rolling line into two 1.5 Mtpy twin co-rolling lines
CONTACT: Email: a.deluca@danieli.it
T
oday, for Danieli the MI.DA. technology is a strategic product and a primary element of its vision of the near future. With the Twin-MI. DA.-configuration it is possible to design and supply a large-scale micromill capable of producing up to 1.5 Mton of finished products in endless configuration, with very high efficiency both in terms of environmental sustainability and energy savings to minimize CO2 emissions, as well as to preserve natural resources. The MI.DA. was initially conceived as a regional plant capable of producing up to 300,000 tpy, equipped with a single rolling line with a maximum hourly productivity of 50 tons. It was designed to meet the demand of a limited area surrounding the plant, with more competitive operating costs compared to traditional minimills of greater size. In the past decade, the MI.DA. technology made it possible to define new milestones in the progress of minimills, and to achieve goals that led Danieli to conso-
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lidate its technological position in the endless casting and rolling process, a development that started in 1998 with the ABS Luna plant. Since then both process and technology have been consolidated and several successes have been achieved, starting with CMC Arizona in 2009, passing through the latest startup of the two Egyptian Steel MI.DA. facilities for IIC in 2016 and NPSS in 2017, and the CMC #2 plant early in 2018. Through the years Danieli has been able to cast steadily at speeds up to 7.0 m/min with even higher speed peaks, as well as to increase the overall process yield to 99% with 94% plant uptime. Now, thanks to the latest technological developments, Danieli ECR Endless Casting and Rolling process is a well-proven, reliable and cost-efficient way to produce rebar in bars, spooled coils and wirerod, and is presumably going to completely supersede the conventional minimill concept, mainly due to the revolutionary introduction of the twinstrand application to produce up to 1.5 Mtpy of finished products to match the ever-increasing market demand. In the
last two years Danieli has sold six MI.DA. plants with production capacity varying from 300,000 tpy up to 1.4 Mtpy, as a prompt response to ever-increasing demand for plants with higher productivity, larger product range and higher level of automation. Today, in China – a country of big numbers – the regional steelmaking concept is being expanded to meet customers demand for maximized production, while maintaining the consolidated operational advantages of MI.DA.
Key Technologies Such a productivity can be achieved due to the application of the latest FastCast Technology which is the new generation of continuous casting machines with increasingly competitive transformation costs. The Eco Power Mould is a further development of the Power Mould concept with the following improvements: • New geometry of the cooling channels with higher thermal exchange • Lower overall Cu thickness • New coating layer to improve rigidity • Reduced off-corner cracks resulting in increased sub-surface quality
March 2020 / MPT International
Source (7): Danieli
AUTHOR: Andrea De Luca, Danieli
