SSAB’s Hardox 500 Tuf raises the bar for strength, hardness and toughness
The Hardox 500 Tuf, which has a narrow Brinell hardness window of 475-505 HBW, combines the hardness of Hardox 500 with the toughness of the Hardox 450, delivering high strength, extreme hardness and guaranteed toughness in one and the same wear plate, making it suitable as a structural material in heavy-duty tipper bodies, containers and buckets, even in freezing conditions.
Typical working conditions for a tipper body made with Hardox 500 Tuf are the loading and unloading of heavy and sharp rocks in quarries and mines, handling large and heavy steel scrap, and in demolition when pieces of concrete with rebar are loaded or dropped into tippers.
Hardox 500 Tuf has a guaranteed impact energy of 27 J at -20°C (20 ft-lb at -4°F) and a typical value of 45 J at -40°C (33 ft-lb at -40°F). According to calculations with SSAB’s WearCalc and TippCalc calculators for sliding wear with granite, Hardox 500 Tuf can deliver double the service life compared to Hardox 400. The steel can be processed by the same kind of machinery used for other Hardox grades. Bendability recommendations are similar to those for Hardox 450.
Manufacturers using Hardox 500 Tuf can choose to increase wear life or increase payload, or both. Using a thinner plate in Hardox 500 Tuf can provide 10–15% greater load capacity for a dumper or container. Staying with the same thickness on the other hand will give a 30% longer service life or more, depending on the abrasive material.
In addition to high wear resistance, Hardox 500 Tuf is tough enough to perform as a structural wear steel. This offers new opportunities to reduce or exclude the supporting structures. Hardox 500 Tuf can be processed with the same kind of machinery used for other Hardox grades. Bendability recommendations are similar to those for Hardox 450.
Sweden-based Zetterbergs which manufactures truck dumper bodies, tipper trailers, swap flatbeds and refuse collection superstructures, manufactured a fourth-generation dumper called ZD4 by using Hardox 500 Tuf, which allowed for a 20% or 650 kg (1433 lbs.) reduction in tare weight. The company reported that that the lifetime of its dumpers increased by 40% after using Hardox 500 Tuf.
Another Swedish company Rådmansö Schakt och Transport AB has been using the Hardox 500 Tuf wear plate in a tipper-trailer combination with a maximum load capacity of 38 metric tons. This rig logged 11,000 km in a year after it was delivered early in 2016, having transported more than 40,000 metric tons of abrasive materials, mostly crushed granite rock from the company’s own quarry. In 2017, when measuring the end section of the 6 mm bottom with an ultrasonic thickness probe, it showed wear of only around 5% after more than a year in operation. The bottom and sides showed practically no dents or other signs of damage. Furthermore, the condition of the plate edge looked almost new, according to SSAB’s technical development team that conducted the inspection.