Efficient and reliable abrasion resistant steel sheet withstands harsh wear and tear whilst maintaining lasting quality – even in the most demandin
Valast® 450 is the strongest steel to ever be produced at Tata Steel’s hot strip mill in IJmuiden, which created some unique challenges for its development team.
How do you stop a steel coil becoming one of the world’s most powerful springs? This was the unexpected challenge that Tata Steel engineers were faced with when developing Valast 450.
With a Brinell rating of 450, Tata Steel’s abrasion resistant (AR) strip steel product, Valast, is incredibly strong with a typical tensile strength of 1475 N/mm2 (Rm). This brings numerous benefits – ruggedness, longevity and light-weighting to name a few – but it also creates a number of challenges.
As a strip product, which can be as long as 1200m, Valast 450 is coiled in order to be transported and stored. This in itself was a challenge, due to the immense strength of the steel, but it was overcome relatively easily. As part of Tata Steel’s Strategic Asset Roadmap (STAR) programme, a new, heavy-duty coiler was installed.
Typically, when a steel strip is coiled, it is then held in place by steel straps. This stops the last flap of steel – or the tail end – springing back due to the elastic potential energy in the coil.
However, because of the amount of resistance in Valast 450 is so great, the steel straps couldn’t stop the tail end from springing back. Obviously, with safety being Tata Steel’s absolute priority, our engineers had to find a solution.
Working with the manufacturer of the heavy-duty coiler, Tata Steel adapted a method usually used by decoilers or recoilers. The technology, which had never before been employed by a hot strip mill, intentionally deforms the tail end in a very specific way. This means that, rather than springing back outward, the tail end bends inwards, therefore keeping the energy inside of the coil.
This method was first used in small scale trials and, once the outcome was deemed to be reliable, the technology was installed onto the hot strip mill line in IJmuiden. The result is a coil of Valast 450 that can be handled safely and efficiently.