Potato harvester made of Hardox® wear steel helps farmers harvest success

Located near Turkey’s southern coast, Öz-Eliş was founded in the 1990s as a supplier of repair and maintenance services for agricultural machinery. According to Mustafa Hayta, the second-generation manager of the company, they started to produce potato harvesting machines in 2005 in response to strong market demand. Nowadays, 80% of their production is concentrated in this area.

The company produces a two-row harvester model with a width of 1.5 m (5 ft) and, more recently, a four-row model with a width of 3 m (9.8 ft). While the two-row model is the most widely sold on that market, the company was determined to manufacture a bigger and more efficient model. It began extensive R&D testing that finally led the way to Hardox^® wear-resistant steel.

The Öz-Eliş potato harvester is mounted on the back of a tractor and has blades at the front of the harvester to remove the potatoes under the soil and convey them to a screening belt at the back. The potatoes roll on the round bars of the belt, which are placed as horizontal strips.

In 2005, Öz-Eliş was using heat-treated ST37 (S235) mild steel on the harvester blades in the front of the two-row harvester. Later, they began to use ST52 (S355) steel to overcome frequent bending, wear and fracture problems. However, the desired results could not be achieved.

“We tried ST52 (S235) steel and we even tried to strengthen the steel by applying heat treatment, but still could not prevent the problems we experienced,” Hayta says. He began doing some research and came across Hardox^®. Together with SSAB, the company conducted studies to determine the best product and grade to be used in the blades.

Hayta continues, “We decided that the most suitable products for us were Hardox^® 450 and Hardox^® 500. In sandy soil, we started using Hardox^® 500, which is more resistant to abrasion, while in hard soil we started using Hardox^® 450, which has sufficient abrasion and higher impact resistance. Hardox^® 500 worked almost three times more efficiently than the heat-treated ST52.”

Thanks to the use of Hardox^® wear steel, their challenges with wear, bending and cracks have disappeared. According to Hayta, the blades that offered 350 acres (17.5 hours) of service life in 10 mm (0.394 in.) thick ST52 can now offer 800 acres (40 hours) of service life with 8 mm (0.315 in.) thick Hardox^® 500. 

“With the heat-treated ST52, we often experienced crack problems as well. This problem has disappeared with Hardox^® thanks to its unique toughness,” he says.

The company decided to develop a four-row potato harvester to gain efficiencies using less machinery and manpower.

The harvesting belt of their two-row harvester was made by lining heat-treated 41CrMo4 mild steel bars 1.5 m (5 ft.) wide and 13 mm (0.512 in.) in diameter. The width of the four-row harvester had to be 3 meters, which required using steel bars 3 m long (9.8 ft) and 13 mm (0.512 in.) in diameter.

“At that time, it was not possible to supply steel bars in the length we needed in one piece with local heat-treated solutions. We used 41CrMo4 steels in two parts – but we didn’t get the result we wanted,” Hayta says. “Heat-treated mild steel had many problems. There were serious differences between the hardness in one area and in another area. Moreover, the high hardness was only true for the surface of the material. Hardness decreased even further as it went from surface to center. The toughness of the material also decreased due to the heat treatment. These shortcomings caused problems, such as rapid abrasion, bending, cracks and fractures.”

Despite a three-year search, Öz-Eliş could not find a solution for 3-meter-long (9 ft. 10 in.) steel bars. That’s when SSAB engineers came into the picture.

“We talked to SSAB about how we could solve this problem. Since there were no ready-made materials in the desired sizes, SSAB produced special solutions to support our R&D work,” Hayta says. Steel round bars, 3 m (9.8 ft) in length and 13 mm (0.512 in.) in thickness, were custom made and delivered to Öz-Eliş so they could finalize their R&D. Hayta and team were so thrilled that they headed right for the fields to assemble the bars, not even waiting to paint them.

“We saw that the new machine did wonders – even in the first 10 meters (32 ft. 10 in.). Our three years of work finally began to bear fruit. All the farmers came to us and congratulated us. It was a great feeling!”

As Hayta continued testing, he realized what the material’s unique combination of hardness and toughness meant. “In the following stage, we also started to use Hardox^® 400 steel bars in our two-row, 1.5 m (5 ft.) models and saw the wear life increase from 350 acres to 1,200 acres (2,400 acres in 4 rows). In addition, we’ve avoided the bending, cracking, breaking, and other problems we had before,” he says.

“Our biggest motivation is to satisfy farmers,” Hayta continues. “We make things easier for them and help them make a better profit. Farmers who don’t recognize Hardox steel are looking at the result, not the material we use. We can only show them how we improve our quality with Hardox^® after the harvest is finished.”

Hayta also noted that market competitors are trying to compete on price. He confidently tells farmers who compare his company’s models with other competing machinery: ‘Take our product, and call us after 1,000 acres of harvest’ – a statement that squarely sets them apart from their competitors.

Öz-Eliş is continuing its efforts to become even more successful in the production of potato harvesters. The company has two main goals for the near future: reduce weight by using Strenx^® performance steel in the structural parts, and use Hardox^® 500 Tuf, which provides the hardness of Hardox^® 500 with the toughness of Hardox^® 450 for stony soils where the impact risk is higher.

Hayta says that because of the lightness in the structural parts, farmers can use the harvester even as an attachment for smaller tractors. For this, they intend to focus on innovative design and materials and benefit from SSAB’s products and technical support.

Other innovations are also on the horizon. “We currently use Hardox^® 500 in our harvester blades for sandy soils, but in some soils we encounter too many stones. We use Hardox^® 450 to prevent damage from impact. To increase the wear life even further, we want to switch to a hardness of 500 BHN. So we’re going to experiment with Hardox^® 500 Tuf. This way, in stony fields we’ll more easily fight both abrasion and cracking.”

Find out how you can benefit from Hardox^® in your farming operations. We’ll be happy to meet you in person and find out about your specific wear environment to find the best and most cost-effective solution for your business.