2006
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Hong Kong - China
Control system upgrade for 750,000 ton/yr bar mill reduces gap time between billets
Shiu Wing Steel contracted Russula to upgrade the 750,000 tpy bar mill, located in Hong Kong, China. The original control system was installed in 1998 and delivered in a “black box”. One of the limitations of a closed control system is that Shiu Wing Steel’s maintenance team could not make any modifications to the configuration. When it came to replace the system due to obsolescence, the production and maintenance management sought to change the system to an open based programming system with future upgrade packages to improve the operating performance.
"After having a black box which would not allow us to make modifications, we wanted an open system. Russula listened to us and met our demanding requirements."
Scope of Supply
The project scope included electrical engineering, hardware, software development, installation supervision, commissioning, and training. The new automation system included the latest recipe management system, cascade speed control, low tension control and automatic loop control. The shear control was implemented with the specific positioning cards for increasing the shear accuracy and performance.
- Siemens S7-400 Controllers and Siemens RT400 PLCs
- Wonderware InTouch HMI
- IBA System high speed data acquisition system
- Profibus commnication
Results
As a result of the control system upgrade, the production rate increased due to the reduction of the gap time between billets from 5 seconds to 2 seconds. Due to higher process stability, the plant can produce at tighter tolerances. In addition, the new control system has allowed the plant to reduce the gap time between billets.
In the two years following the control system upgrade, Shiu Wing plant management has observed that the plant is running better after the upgrade. The production staff has better control of the process. As a result there is less off grade and scrap.
"Russula had a quick and precise response to our needs. They transforemed words into action showing confidence in their work."
About Shiu Wing Steel
Shiu Wing Steel is the only steel rolling mill in Hong Kong and has been the leading manufacturer and retailer of reinforcing bars since 1950. Shiu Wing has a production capacity of 750.000 ton/yr and produces hot rolled steel rebars.
