Yu Q.,Nucor Steel Tuscaloosa Inc. |
Beard A.,Quaker Chemical Corporation
AISTech - Iron and Steel Technology Conference Proceedings | Year: 2014
In the past decade, roll bite lubrication has been used in continuous hot strip (tandem) mills widely. However, it is relatively new technology for a reversing hot rolling mill to apply the lubrication at the roll bite and the contact zone between the back-up rolls and work rolls. Roll lubrication was introduced to the 4-h Steckel mill at Nucor Steel Tuscaloosa in 2011. After collecting data in a lengthy trial, it was concluded that the benefits included a significant extension to roll service life and notable reduction of mill torque. Nucor Steel Tuscaloosa quickly made the decision to apply the roll lubrication by installing a permanent system. This paper will describe the mechanism of lubrication in the roll system and present the improved rolling parameters of the Steckel mill. © 2014 by AIST.
Lara M.,TMEIC |
Nelko S.,NUCOR Steel Tuscaloosa Inc. |
Fukuma K.,Toshiba Corporation |
Hosoda H.,Toshiba Corporation
AISTech - Iron and Steel Technology Conference Proceedings | Year: 2013
TMEIC achieved the goals set out in this reactive power compensation project. The voltage fluctuation during rolling (that was limiting the maximum overload capability of the DC drive system) has been reduced to approximately 50% of the original values. In addition, new Up-coiler and Furnace Drums AC inverters and induction motors are being fed from the same converters. These new drives and motors also help in reducing the maintenance cost when compared with the old DC motors fed from Synchronous motor-DC Generator sets.
Yu Q.,Nucor Steel Tuscaloosa Inc. |
Seibert A.,Nucor Steel Tuscaloosa Inc.
Iron and Steel Technology | Year: 2013
A tension model for wide, heavy-gauge coils is developed via transferring the bending torque into the tension by introducing the concept of wrapper angle. The bending torque is obtained by calculation of the elasto-plastic deformation work of the bending moment. This is different from the existing model that assumes a rigid-plastic deformation through the entire strip thickness. Utilizing the maximum tension generated by the pinch rolls and the position of the second wrapper roll, the upper and lower limits of the wrapper angle are established, which could carry out a permissive tensile stress range for tension control. By applying a constant wrapper angle, a non-linear taper tension pattern is introduced and analyzed. Compared with the constant tension pattern, the nonlinear taper tension pattern has advantages as follows: • A high tension could be applied to the head of the strip to prevent telescoping of inner wraps caused by either bad shape or cold temperature. The high tension declines with the increase of outer diameter of coils, which could avoid acceleration after the tail-out of the strip. • The total torque of the non-linear taper tension decreases with the increase of the outer diameter of coils, which provides a possibility to raise the maximum tension of the pinch rolls without increasing the torque capability of the mandrel. This feature leads to the installation of a drive-train system for the top pinch roll. • For strip length shorter than that of the runout table, the prediction of the maximum limit of tensile stress is able to help the upcoiler to establish cinch and to smooth the strip speed after the cinch.
Norris A.,Nucor Steel Tuscaloosa Inc. |
Reinhold D.,Nucor Steel Tuscaloosa Inc.
AISTech - Iron and Steel Technology Conference Proceedings | Year: 2012
Integrating the format OSHA 10 materials/method into a teammate/work centered format worked well with NSTI's employee empowerment culture and goal of continuous safety improvement. The team was able to further develop as a cohesive unit, enhance our partnership with OSHA and continue to drive the safety culture and performance in the facility towards excellence.