3 times longer service life for recycling drums made in Hardox® HiAce steel, compared to stainless steel

As Sweden’s leading recycling company with 90 facilities across the country, Stena Recycling uses large steel drums to clean and separate non-ferrous metals at a rate of about 1,000 tonnes (1,102 tons) a day. Since it’s a wet recycling process, the water makes the wear environment corrosive. This caused excessive wear, resulting in high maintenance costs and disrupted operations. Stena Recycling had to find a better solution than stainless steel. It came in the shape of Hardox^® HiAce.

When the Hardox^® Wearparts center KA Industriteknik redesigned Stena Recycling’s recycling drums, it increased service life by up to 3 times for the grid segments, compared to the previous solution using stainless steel. Not only does it save money with reduced maintenance for Stena Recycling, but it reduces the amount of steel used on a yearly basis. This translates to an impressive CO₂ reduction from steel production, down from 56 tonnes (62 tons) of CO₂ per year to 8 tonnes (9 tons).

“With the new design of the grid segments in our recycling drums, we could reduce the maintenance by around 70%. Since the grid plates in Hardox^® HiAce steel are only 4 mm (0.16") thick and weigh a mere 10 kg (22 lbs.), replacement is very easy. The curved plates are also in Hardox^® HiAce and we estimate the drums will last around 4 years, compared to 2.5-3 years for the previous material. We process up to 1,000 tonnes (1,102 tons) of recycled steel every day and the water we use is rather aggressive. We can really see the difference in reduced corrosion with Hardox^® HiAce.” Kent Brännlund, site manager at Stena Recycling’s plant in Halmstad, Sweden.

The grid segments developed by Hardox^® Wearparts center KA Industriteknik utilize 4 mm (0.157”) plates of Hardox^® HiAce steel, which are slit to allow the water to pass through. The previous solution using stainless steel had a shorter lifespan due to wear and impact, since the stainless steel is not as hard and strong as Hardox^® HiAce. Stena Recycling runs the grid down to approximately 3 mm (0.118”) before replacing the segments, which translates to about a 3 times longer service life than for the stainless segments.

“We have used Hardox^® 450 wear steel in our equipment before and we have been able to transfer to Hardox^® HiAce without any problems. In the workshop it behaves practically in the same way when it comes to cutting, bending, welding and other processing. We cut the grid segments with abrasive water jet to avoid any heating which otherwise could affect the steel’s properties.” Kim Andersson, owner of KA Industriteknik, Laholm, Sweden.

Hardox^® HiAce is developed by SSAB with the main objective to tackle corrosive wear. It has a nominal hardness of 450 HBW, the same as Hardox^® 450. Hardox^® HiAce shares many other properties with Hardox^® 450. Both grades have high impact toughness, 27 J at -20°C (20 ft-lb at -4°F), and consistent, high-performance workshop properties. Under non-corrosive wear conditions, they provide the same long service life. The difference is in wet and corrosive environments, where Hardox^® HiAce can increase the wear life threefold or more.