A team in Liège has invented a unique sensor for the plant’s galvanising line. Since early November, the pickling baths on galvanising line no. 5 have been equipped with a new sensor that is the result of a collaboration between Liège’s engineering department, the University of Liège and the galvanising line team.
Michaël Scherer, technical administrator and electrician on galvanising lines no. 4 and no. 5, gives us an insight into this exciting project.
Every pickling line in the steel industry is equipped with a catenary sensor that is used to indicate the height of the strip in the acid bath. This helps ensure optimal pickling.
The galvanising line in Flémalle (Liège) that is used to treat hot rolled coils is also equipped with a pickling line. The sensor on the line needed replacing.
“In fact, many of these sensors date back to the ‘70s. After a technical failure which could have affected the functioning of the line, we decided to get a new sensor to mitigate any future risks. But we couldn’t find anything suitable on the market so we decided, together with my colleague Thierry Devaleriola – who’s a research analyst in electrical automation – that the only solution was to make one ourselves.
Thierry and I worked together with Laure-Anne Gerardy, civil engineer at Liège University who at the time was still a student. She based her final dissertation on the development of this sensor.
This type of sensor must be able to detect the strip at a distance of 30 to 40cm, but it has to be placed outside the acid containers. Over the course of six months, we tested several configurations. Laure-Anne worked on the physical and electromagnetic aspects of the sensor and Thierry finalised the electronic part. It was an extremely rewarding experience for all of us.
The new sensor has several advantages. A higher frequency gives it a shorter response time and it works even when there are steel sheet thickness changes. It also uses less power, cutting the need for warm-up time; it is easier to maintain; uses standard components and is more sensitive.
All of us – the team on galvanizing line no. 5, the engineering teams and the University of Liège – worked really well together and we are extremely proud of this project. Several other sites are now enquiring about the sensor – and I think this is just the beginning of the interest we will see in this project…
Picture (from left to right): Bruno Bianchin (technical administrator – electrician), Michaël Scherer (TAZ – electrician), Olivier Lenaerts (TAZ – electrician), Thierry Devaleriola (research analyst electricity-automation), Laure-Anne Gerardy (civil engineer), Jacky Sanza (shift electrician).