The 5-stand, 4-high tandem cold reduction mill has an annual production capacity of approximately 1.1 million tons and can reduce pickled hot band 0.055–0. 191 inch thick to 0.0124–0.075 inch thick cold rolled strip 36–72 inches wide. The mill has a total power rating of approximately 31,500 hp with a maximum strip delivery speed of 4,100 feet/minute.
With a continuous variable crown (CVC) system on all stands, the cold mill can produce a wide range of strip widths with a relatively small number of work rolls. The CVC systems have a ±3.9-inch stroke and a crown variation of .013 in. The mill also features a closed-loop shape control with a shape roll in the exit of the last stand that is connected with the hydraulics of a work roll bending system of 150 tons capacity (positive or negative bending). Automatic gauge control is driven by a closed-loop x-ray system.
Line equipment includes an entry-end scissor shear and a quick-change coupling system. There is a rotary shear on the exit side of the mill, as well as an inspection station and two exit tension reels. Coils are then removed by an overhead crane to an 88,000 sq. ft. storage bay for further processing.
All stands are equipped with forged steel rolls and taper roller bearings. Automatic roll changing can occur with strip in the line. Typically, there are 10 work roll changes per turn, with three backup roll changes every week.
Ancillary facilities include a rolling oil solution system with two 60,000-gallon tanks for stands 1 through 4, and a 17,000-gallon tank for stand 5. There are magnetic separators, a flat bed filter and back-flush filters. The roll shop includes two roll grinders, an electronic discharge texturing machine and chrome plating equipment.
|
