Smart sensors in the hot rolling process

12/02/2020 - Innovation and R&D

For the last two years, research and development (R&D) teams, in close collaboration with operations experts, have worked together to create a sensor to measure the optimal quantity of deoxidation powder to be injected in the tubes. This specific step in the hot rolling process has been flagged as a high priority for quality improvement. This development is a new illustration of our advances in the field of Industry 4.0. The sensors will be implemented in North America in the first quarter of 2020.
The injection process of the deoxidizing powder into the tubes, after they have been pierced and before they are elongated, is a delicate one. Too much powder will result in defects inside the tube, while too little powder means the manual cannot be extracted from the shell. Quality of the pipes is therefore largely dependent on this process and finding a solution to the issue was crucial. Until now, mills have had to find their own solutions to a technical challenge that results in a high percentage of rejected tubes.

The problem-solving phase began with a workshop organized between R&D and production experts from all the regions. It was quickly determined that the best solution would be a sensor to help determine the optimal dose of powder. The R&D team first explored existing sensor options, but none were available on the market for this highly specific process. So the team decided to create one themselves.

Piloting the sensors in North America

Based in Riesa, Germany, the R&D team conducted pre-studies and analyses before prototyping a sensor. After two years of work, they are now ready to pilot the sensor in the United States.

The US mills have the most significant challenges with tube interiors,” says Mark van der Logt, Head of Research Center Technology in Germany. “As a result of the unstable process, they have challenges with a reliable injection of the deoxidation powder. We decided quite early on that North America would be the place to pilot the sensors.”

Contributing to industry 4.0

Beyond measuring the precise dose of powder, the sensors will also track data from the tube-rolling process. That data, when analyzed, will help us create simulations of the different steps of the process, giving us new ways to improve and standardize quality. The ultimate goal is to create predictive models.

“Our plan is to monitor the process as closely as possible, so we can identify deviations from normal operations. That will allow us to alert operators so they can course-correct rapidly,” says Mark. 

Sharing insights and expertise

While the sensors are high-tech, they also have to be easy to use and maintain. “We needed to build sensors for the real-world environment,” explains Mark. “They have to be simple to use, easy to maintain and not require extensive training.” The R&D team’s close collaboration with regional production experts ensured the sensors were developed to meet those challenges. They are calibrated with all the settings and powder dose ready to deploy.

“To build something like this successfully, you need both R&D and operations teams to work together. R&D doesn’t always have insights into operations, and operations doesn’t have the same resources as R&D. It’s a very collaborative process,” says Mark. Both teams met regularly throughout the two-year development process.

We’ve seen significant progress in interior quality with the sensors. Our goal is to take interior quality to the best level ever and greatly reduce the percentage of rejected tubes.

Mark van der Logt Director of the Technologic Research Center in Germany