Quicker positioning helps steel mill meet customers' demands

To extend the range of its steel piling sections to include several new designs with tighter tolerances, British Steel sought new control systems and drives for its roller straightening machines (RSMs) in its heavy section mill in Scunthorpe, North Lincolnshire, U.K. Upgraded piling sections help increase construction efficiency because they can be driven faster when making steel walls.

05/01/1998


To extend the range of its steel piling sections to include several new designs with tighter tolerances, British Steel sought new control systems and drives for its roller straightening machines (RSMs) in its heavy section mill in Scunthorpe, North Lincolnshire, U.K. Upgraded piling sections help increase construction efficiency because they can be driven faster when making steel walls.

The mill had been upgrading its quality and product range for two years, which increased demand and volume. This required faster and more accurate setups of the RSMs for new structural sections, more precise feedback for accurate positioning, as well as improved data acquisition and storage, communications, and an operator interface to visually display parameters, mimics, trends, and other data.

The mill traditionally produces channels, beams, columns, and sheet piling sections up to 630-mm wide in a range of lengths, weights, steel specifications, and finishes. Each machine has seven straightening rolls, adjustable for each new section. The seven roll spindles have horizontal, vertical, and axial plane movement and are motor-controlled to make sure the rolls are aligned properly and correct straightening forces are applied.

Section straightness is ensured by two RSMs, one for lighter beams and pilings with up to 1,400 roll centers and another for larger sizes with up to 1,800 roll centers. Control Techniques (Leeds, U.K.) won the contract to improve the larger RSM.

"Successful machine setup previously relied on the operator, but our new position control helps achieve product straightness more quickly and maintain it," says Graeme Hornsby, British Steel's operations director. "Upgrading the RSM allows us to store configurations for each size and type of product. It also gives us rapid repeatable setups, improved reliability, and easier future upgrades."

New controls, new performance

Control Techniques' system includes 18 vector drives—from 2.2 to 25 kW—for the RSM's critical positioning drives; Directax positioning modules that calculate the roll spindles' positioning; Mentor drives for dc motor control; and a GEM400 programmable logic controller (PLC) that communicates with the mill's VAX supervisory computer, operator controls, and positioning system.

The drives are controlled by the Directax intelligent motion controllers, which calculate velocity profiles under which the vector drives operate. Each positioning drive motor is fitted with a 1,024 ppr encoder that provides position feedback to the vector drive to within 1,000th of a revolution. Required movements are entered into the PLC and downloaded into the Directax controllers, which enables the drive, then supplies speed profiles to move the vector-controlled motor accurately.

"Recipes" of the best configurations for optimum straightness for each product are stored and retrieved as needed. Control Techniques' system also include full-status monitoring and a full-logging alarm system with 1,000 conditions.

"The new system will pay for itself quickly because setups between products that used to take 10 or 20 minutes can now be achieved in seconds," says Mr. Hornsby. "We no longer need the position transducers and limit switches, which were often knocked off the machine or damaged. The operator can now see where the rolls are without having to measure positions, which is much easier and more accurate. We now have over 200 setup variations stored, and our product quality has never been so good."

For more information, visit www.controleng.com/info .





No comments
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by...
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Intelligent, efficient PLC programming: Cost-saving programming languages are available now; Automation system upgrades; Help from the cloud; Improving flow control; System integration tips
Smarter machines require smarter systems; Fixing PID, part 3; Process safety; Hardware and software integration; Legalities: Integrated lean project delivery
Choosing controllers: PLCs, PACs, IPCs, DCS? What's best for your application?; Wireless trends; Design, integration; Manufacturing Day; Product Exclusive
PLCs, robots, and the quest for a single controller; how OEE is key to automation solutions.
This article collection contains several articles on improving the use of PID.
Learn how Industry 4.0 adds supply chain efficiency, optimizes pricing, improves quality, and more.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

Special report: U.S. natural gas; LNG transport technologies evolve to meet market demand; Understanding new methane regulations; Predictive maintenance for gas pipeline compressors
Cyber security cost-efficient for industrial control systems; Extracting full value from operational data; Managing cyber security risks
Drilling for Big Data: Managing the flow of information; Big data drilldown series: Challenge and opportunity; OT to IT: Creating a circle of improvement; Industry loses best workers, again