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Siemens Applying New Rail Technology for First Time in Chinese Long Products Rolling Mill

Baotou Iron & Steel (Group) Co. Ltd., a Chinese steel producer, has awarded Siemens Metals Technologies an order for the supply of a new facility for the inline thermal treatment of heavy-duty rails, to be installed in one of the two company's long product rolling mills in Baotou, Inner Mongolia. This will include the world's first application of an advanced technology for rail hardening, which has been jointly developed by Siemens and the Italian technical center, Centro Sviluppo Materiali S.p.A. (CSM). This Injector Dual-phase Rail Hardening system, named Idrha+, enables rails to be produced with improved resistance to contact fatigue and wear. The new inline system will also optimize the rail product performances according to the different grades of steel, which may be processed reliably and flexibly. It is scheduled to be commissioned at the beginning of 2014.
Baotou has a total long product rolling capacity of 2.1 million tons per annum. The Idrha+ system will be installed in a rail rolling line which has a 400,000 tons per year capacity and rolls various sizes and shapes of rail, including asymmetric rails, in special steel grades with carbon contents ranging from 0.6– 0.8%. The maximum hourly productivity is 150 tons of rails up to 104 meters in length.
The design of the Idrha+ system from Siemens and CSM, which will be used on the rail rolling line commercially for the first time, is based on thermomechanical and metallurgical process models, and was validated by experimental trials in pilot plants. The final rail product performances are in accordance with the Chinese standards in terms of hardness, while the resistance to both contact fatigue and wear is improved. It also allows the simulation of various cooling strategies for different grades of rail steel prior to the start of production. This enables run-up times to be reduced, nominal capacity to be attained more quickly and relevant performance parameters to be fulfilled consistently and reliably. 
Within the project, Siemens is responsible for the entire process technology, and for engineering its own deliveries as well as the equipment to be provided by the customer. The scope of delivery from Siemens includes the induction furnace, a highly flexible quenching line, and closed-loop process automation. Siemens will also support installation and commissioning. The delivery scope also includes the joint development and definition of new rail steel grades with Baotou Iron and Steel, as well as assistance with grade certification for the international market.
Pictured below: The "Injector Dual-phase Rail Hardening" system (Idrha+) enables rails to be produced with improved resistance to contact fatigue and wear.

The Baotou Iron and Steel (Group) Co., Ltd. in Inner Mongolia has a total production capacity of ten million tons of steel per annum. It produces cold and hot strip, heavy plate, seamless pipes, steel girders, and bar and wire steels. Baotou is one of the three locations in China where rails are produced. Siemens has already carried out two modernizations in this long-product rolling mill. It installed a new shear and a new pinch roll in 1999 and, in 2005, four new rolling stands and an optical alignment system were installed in the plant, the temperature control system was also modernized.