To address the alarms, a situational-awareness type approach was deployed, with a solution based around a ‘dark-desk’ philosophy.
To the operators, the control room screens appear subtle and bland but when something goes wrong it really jumps out.
Jan explains: “When there aren’t any alarms, the screens are a symphony of grey. When alarms do appear they will only be apparent in one of four primary colors – blue, yellow, red and green – in fact these are the only colors used in the in the operator works stations .”
The primary remit for the alarm delivery and management system was to follow EEMUA 191 guidelines, a standard for the design and management of alarm systems.
Since it was first published in 1999, EEMUA 191 has become the globally accepted and leading guide to good practice for all aspects of alarm systems.
The kilns have radiation-based level transmitters, which are used to gauge the stone level.
The problem is the stones can back up or bridge and then drop, so the actual level will fluctuate. One alarm that kept appearing with the old system was ‘stone level low’, which triggered every couple of minutes across all four kilns.
“When we were translating the software from the original system we looked at the entire state of the alarms, rationalised them and then classified them based on importance,” Jan explains.
“We utilized the ability of operators to shelve the alarms too, in effect snoozing or hiding them for a while to give engineers the time to fix any issues.”
There are still over 2,800 potential alarms in the system, but the shelving functionality allows the operators to consciously tidy up the alarm screen and prevent the alarm logger being continuously stamped.
Since the installation, the new control solution has been working as designed and has proven to be a more than capable replacement for the older system.
Along with the significantly reduced risk of failures, Tata Steel is also seeing many other benefits of a contemporary control solution.
These include: far more effective data management, thanks to FactoryTalk Historian; the effective collection and collation of real time data, allowing the company to make better informed role-based business decisions; and clearer data presentation and disbursement thanks to FactoryTalk VantagePoint.
The use of an EtherNet/IP communication backbone has also allowed Tata Steel to exploit the power of The Connected Enterprise.
The new control solution not only connects to the site’s ERP system, but also to its quality system, laboratories and its road & rail logistics system.
The use of an EtherNet/IP-based communication protocol also gives InControl the ability to ‘dial in’ to the site to remedy any issues without having to undertake costly engineering visits.
Jan adds: “A lot of people are wary of letting you touch their kilns. If you wreck the refractories, it costs thousands to fix.
We have proved that modern control solutions can be implemented in incredibly short time windows and at a very attractive price point.
We have now modernised four kilns at Shapfell and are eager to let other Maerz kiln operators know that we now have a standard tried-and-tested solution.”
According to Ian Busby, engineering Manager at Tata Steel’s Shapfell plant: “We needed a solution that would offer us good reliability that could help us replace the older system in stages without disrupting the production.
We also went for a system that would be supported by readily available spares and one that could deliver remote support. The Rockwell Automation-based solution ticked all the boxes.
“We are now seeing more real time information,” Ian concludes, “so trending is a lot more straightforward.
The next stage will be to look at increasing efficiencies at the plant, which will be more straightforward thanks to our new data capabilities and the ability to easily add more hardware.”
Allen-Bradley, ControlLogix, FactoryTalk View Site Edition (SE), FactoryTalk Historian, FactoryTalk VantagePoint, LISTEN. THINK. SOLVE., PlantPAx, POINT I/O and Rockwell Automation are trademarks of Rockwell Automation, Inc.
EtherNet/IP is a trademark of ODVA, Inc.
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