Authors: G. Boulton, R. Davies, J. Edwards, K. Hochstetter, P. Thomas (Hatch IAS) and T. Rojas, Bluescope Steel Limited
AISTech Conference, May 2009
Abstract
In February 2007 Industrial Automation Services Pty Limited (IAS) were awarded the fixed price contract to upgrade the Bluescope Steel 3500mm 2-stand plate mill hydraulic thickness control system (HAGC). Justification for the project was the obsolescence of the existing 1986 vintage DEC PDP11/73 based system. The project scope included:
- Replacement of the HAGC computer system, while retaining existing process IO wiring to external devices and mill equipment
- Interfacing the new HAGC system to the mill control computer (MCC) and the stand controller PLCs
- Replacement of operator HMI screens (provided by the client)
- Meet performance guarantees for plate thickness and camber
- Supply new Sony Magnescale position transducers for cylinder position measurement
- Provision of engineer training in the new system
- Design of new housings for the replacement Sony Magnescale transducers
- Design modifications to reduce flexing and vibration of the trays, which are attached to the hydraulic pistons and provide a contact point for the Sony Magnescales, under mill impact loads
The design aspects of the latter two scope items posed a new challenge for an automation system vendor. The tray design modifications required vibration modeling and analysis, in conjunction with measured vibration data from the client. Other challenges were the substantial financial penalties for failing to meet critical deadlines during the course of the project, and the use of a new PLC platform for the new system implementation.
