Page Tools
Sign up to receive ArcelorMittal Flat Products Industry news alerts by email
Page tools
Share on
Contact us Contact us

New investments produce perfectly flat Amstrong® sheets free of internal stresses

ArcelorMittal Downstream Solutions Poland (AMDS) has incorporated new stretch-levelling equipment in its existing cut-to-length line in its Kraków Steel Service Centre which can provide customers with perfectly flat sheets of Amstrong®. These advanced high strength steels (AHSS) have a range of applications in products used in the manufacture of yellow and green goods, railway equipment, and machinery. The investment introduces automated control and measurement of the flatness, internal stresses, and geometry of the strip, during the rolling and cut-to-length processes. For customers, this makes trouble-free processing a reality during their automated laser and plasma cutting operations. The investment in the stretch levelling line was made possible due to a grant from the EU.

The investment at AMDS Kraków will provide best-in-class flatness to customers who rely on fully automatic laser-production lines to process Amstrong® grades. To operate successfully, these lines require AHSS material which is perfectly flat and free of the internal stresses which are typically generated during rolling operations. Market demand for ultra flat products is expected to boom in the coming years, particularly in the Eastern European region.

From left to right: Rafal Nawrat, CEO of ArcelorMittal’s Steel Service Centres in Poland, Urszula Dzierzon, Head of Distribution for AMDS Poland and Kamil Pyzynski, Engineer at AMDS Poland  

Automated laser cutting possible

“Our existing line meets the needs of around 98-percent of our customers in terms of flatness,” notes Rafal Nawrat, CEO of ArcelorMittal’s Steel Service Centres in Poland. “But this is not flat enough for automated laser and plasma cutting lines. These customers require a guarantee that the sheets have a maximum deviation of just three millimetres per metre of material. With the new stretch levelling line, we can make that guarantee.”

AMDS Kraków can produce Amstrong® sheets with a maximum deviation of just three millimetres per metre 

The technology measures the waviness of the steel as it enters the stretch levelling line. “Depending on the result of that measurement, the line will choose whether the coil will be rolled using a standard roll leveller, or the stretch leveller,” explains Kamil Pyzynski, Engineer at AMDS Poland. “The stretch leveller is slower, but guarantees that the material will be below the waviness threshold required by automated cutting lines.”

As well as the stretch leveller, the line includes tools which measure the geometry of the steel sheet and the internal stress in the steel. “All three parts are connected through the line control system,” says Kamil Pyzynski. “This enables us to correct edge waviness and reduce the stress within the steel through plasticisation. The result is an AHSS sheet which can be used on automated lines without disrupting the customer’s production flow.”

The new line includes tools to measure sheet geometry and the internal stress in the steel

Amstrong® properties unaffected

The mechanical properties of the Amstrong® steel are not affected explains Urszula Dzierzon, Head of Distribution for AMDS Poland: “Like all Amstrong® grades, the material maintains good formability and excellent weldability, even after stretch levelling. We have tested the material in an accredited laboratory both before and after levelling. The laboratory has confirmed that there is no statistically significant impact on the steel’s mechanical properties.”

“As Western Europe Service Centres already propose the Amstrong® laser in their portfolio, with our investment in Kraków we ensure that any customer in Europe can easily access to perfectly flat sheets of ArcelorMittal Amstrong® steels” says Rafal Nawrat.

Demand ramping up

Customer response to the stretch leveller implementation has already been significant notes Urszula Dzierzon: “Our customers have been requesting perfectly flat AHSS for some time as it allows faster processing and less disruption to automated cutting lines. With the commissioning of the stretch levelling line in Kraków we are now able to meet these requests. In initial trials customers have been very impressed by the material and we expect our order book to fill quickly during 2023.”

The stretch levelling line ensures customers will be able to use automated laser cutting lines without disruption

About Amstrong® and Amstrong® Ultra

ArcelorMittal’s Amstrong® and Amstrong® Ultra grades are produced at our mills in Dunkirk and Fos-sur-Mer (France), Bremen (Germany), and Krakow (Poland). All mills offer integrated cutting services for steel sheets. Bremen and Krakow also have integrated steel service centres which can provide full processing.

Amstrong® and Amstrong® Ultra have good weldability and are compatible with Class A galvanisation solutions for corrosion protection. 


Copyright pictures

Kamil Pyzynski / ArcelorMittal

lNomad_Soul, Kzenon, Marek Musil /