2014
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Plymouth, UT - USA
Phase 1: Stacker Upgrade at Nucor Utah
Over the course of four years, Nucor Steel Utah and Russula upgraded the automation and drives of rolling mill #2. The project was broken down into three phases. For all phases of the project Russula supplied the electrical and controls solution, installation supervision, commissioning and training.
About the multi-phase upgrade
By replacing obsolete legacy equipment with modern rolling mill control equipment and methods and standardizing the network protocols, the Nucor Steel mill in Utah experienced improvements in maintenance, troubleshooting, control stability and functionality. Ultimately the upgrade, in conjunction with other process improvements, helped increase mill production and product quality. For example, the cold shear area increased from 220 fpm to 310 fpm without increasing wear on the cold shear brake and clutch.
One of the main advantages to doing a multi-phase upgrade is to size the control equipment in phase 1, taking into account the future capacity required when upgrading the rest of the plant equipment in phase 3. When the time comes to implement the successive phases, the switchover time is much faster.
In each phase, Russula re-utilized many existing components from the mill and replaced the obsolete components, which reduced the overall project cost and downtime. This approach is especially beneficial for steel plants with a mix of electrical and automation systems from different suppliers such as Nucor Utah. Hardward standards for the AC and DC drives, remote I/O, network protocol, controller platform, HMI and data acquisition system were selected at the beginning of the project and maintained throughout the subsequent phases.
Nucor Steel Utah new stacker controls layout
The first phase encompassed the upgrade of the rolling mill #2 stacker, evacuation area and storage tables. Russula supplied new Rockwell Powerflex 755 AC drives and new ABB DCS800 DC drives for the magnet power supplies. A selection of hardware was chosen specifically for this project, including Rockwell ControlLogix PLCs, Rockwell GuardLogix PLCs, and FactoryTalk HMI. GuardLogix, a safety PLC, was deployed in 4 defined safety zones with locking gates equipped with ´request to enter´ and ´reset´ buttons. All communication between the PLCs, drives, new operator desks and remote I/O stations are transmitted over Ethernet IP. The new control system improved the safety of the stacker for the operators and maintenance staff.
