Straight from the Labs


The efficiency of iron and steel production has always been decisive for producers to remain cost-competitive. It can be shown that the properties, cost and quality of iron ore are the most important factors that influence the overall efficiency of the subsequent iron- and steelmaking steps. Improving the quality of iron ore benefits the entire process chain. Primetals Technologies has therefore intensified its efforts and activities in the field of beneficiation to support producers to derive the maximum value from their ore. Practical simulation and calculation tools have been developed to assess the suitability of iron ore, and optimized beneficiation measures are proposed for more efficient iron and steel production.


It is an integral part of the DNA of Primetals Technologies to pioneer solutions that will serve steel producers in the world of tomorrow. One such solution is Acoustic Expert, a technology that uses an acoustic fingerprinting method to detect common errors in a variety of steel-plant equipment.


Anna Mayrhofer is leading the R&D efforts behind this remarkable solution. To date, she and her team have developed several different applications for Acoustic Expert. They range from the assessment of material ­quality on conveyor belts to the monitoring of torch cutters in continuous casting machines to the supervision of cooling and lubrication nozzles. Based on the success of these applications, she was approached by one of Primetals Technologies' closest partners, Austrian-based voestalpine, about the possibility of implementing Acoustic Expert in their stockhouse—with the aim of observing the operation of flip-flop screens.

Mayrhofer first created a concept for how Acoustic Expert could be put to work in the stockhouse. The challenge was that her solution would be required to register any tear-up or misalignment of the screen linings used for lump-ore treatment, as well as other potential problems. It was hoped that Acoustic Expert would help ensure that all lump ore would pass through the stockhouse as intended, and that any problems would be identified immediately.


Mayrhofer constructed a mobile version of Acoustic Expert's monitoring equipment to make the installation a simple and straightforward process. She was able to make all of the core equipment fit into one rugged transport box that would withstand the dusty environment in the stockhouse. Both the box and a robust microphone were then installed at voestalpine's facility.

Over the course of six weeks, Acoustic Expert closely monitored one of voestalpine's flip-flop screens. Every deviation from perfect operation was recorded, evaluated, and made transparent. Anna Mayrhofer was able to demonstrate that her solution perfectly met all expectations. Acoustic Expert can now be used in yet another area of steel production—and it surely won't be the last one.

Anna Mayrhofer closely collaborated with partner company voestalpine throughout the entire evaluation period.

The microphone was installed to optimally capture the sound emitted by one of voestalpine's flip-flop screens.

The flip-flop screen's movement ensures that none of the lump ore parts become stuck in the screen lining, even when wet.

Anna Mayrhofer designed a mobile unit of Acoustic Expert's monitoring and analysis equipment for the new site.