Leveling and deburring of stainless steel
Founded in 1982 as a stainless steel trader, NIRONIT Edelstahl GmbH & Co. KG in Rosengarten near Hamburg now offers much more: In addition to trading in sheet and coils, the company also supplies cut-to-size products by means of waterjet and plasma cutting as well as sawing and comprehensive prefabrication. In terms of services, export processing, logistics, warehousing for call-off orders and a whole range of testing procedures round off the spectrum. The material processed at the cutting center in Bremen has a thickness of between 0.5 and 150 millimeters. The parts are also milled, leveled, deburred, rounded at the edges and can receive a surface finish. "Our strength is the extensive stocking and processing of standard stainless steel grades as well as many special materials for a wide range of applications," explains Alexander Ruf, site manager of NIRONIT in Bremen, adding, "If someone is looking for something special and can't find it, they call us." Consequently, the company with its 70 employees is active worldwide.
Surface and flatness important for sheet metal blanks
In its competitive environment, NIRONIT cannot stand still. "We are constantly looking at how we can better present ourselves on the market and stand out from others," says Ruf. With plasma and waterjet cutting technology, blanks with very high cut quality are possible. However, in order to be able to guarantee special surface and flatness requirements of the workpieces, we used to commission external service providers as needed to make this possible."
For leveling, NIRONIT used ARKU's leveling and deburring center for contract leveling work for many years. Most of the time, these were more difficult tasks, as Ruf recalls, because the transport route from Bremen to Baden-Baden is long and the costs must obviously pay off.
"Our goal was to grow qualitatively rather than quantitatively, because you can only get into other segments with precise cut quality, surface quality, flatness and guaranteed punctuality," explains the site manager.
In 2022, company leaders analyzed what equipment was still missing: A leveler, a deburring machine and a laser cutting machine. The latter has already been ordered and is scheduled for delivery in 2024. A FlatMaster® 120 and an EdgeBreaker® 6000 from ARKU, on the other hand, are already in the cutting center.
Only burr-free and flat sheets may leave the production
"According to our quality standards, crooked parts and parts with burrs must not go to the customer," Ruf explains further. With a passage width of up to 1,300 millimeters and a length of up to 2,000 millimeters, these are a case for the EdgeBreaker® 6000. "With the suction table as a support, deburring works very well even with small components," says the site manager.
Crooked parts and blanks are handled by the FlatMaster® 120, although the dimensions can be considerable. The minimum length is 210 millimeters, but the ARKU leveler in Bremen has also handled sheets 6,000 millimeters long and 2,000 millimeters wide. "We have a 6-meter roller conveyor each for the forward and return runs, which works well," Ruf reports. NIRONIT also levels them when the customer does not specifically request it. The parts receive a sticker indicating leveling and a QR code for more information.
"Every stainless steel component has a downstream machining process," Ruf explains. In part, NIRONIT takes over these machining operations together with partners, in part the customer does it himself. Regardless of this, for these downstream processes it is important on the one hand to remove the disturbing burrs. On the other hand, leveling ensures that the residual stresses in the material are reduced. The acquisition of the FlatMaster® has therefore already brought NIRONIT a number of new frame orders. And the leveler can also improve the quality of the plates from the steel mill. "We had a customer who wanted a flatness of 2 millimeters guaranteed," says the site manager, "no factory can represent such a tolerance. However, with the FlatMaster® we were able to meet the customer's request without any problems."
As little effort as possible for downstream processes
This trend toward more quality is generally widespread in the industry, Ruf observes. "Many customers want the parts to be finished and perfect so that they have less work in the downstream processes in the company," he says. In addition, more and more requirements have been added over the years: A chamfer here, a thread there, or an edge rounding. Stress relief is also an issue - when you cut, mill or drill sheet metal, stresses are always released in the metal structure. Leveling relieves these residual stresses, another benefit for Ruf in addition to flatness. "Customers thus have significantly fewer problems in the downstream processes." The site manager goes on to explain, "We had one case where a customer saved almost 300 hours of processing time by leveling within the blanket order."
Ruf has already experienced firsthand how important leveling is. In 2014, he had to go to Ethiopia to accompany a project. NIRONIT had delivered almost 70 tons of material to Addis Ababa - and the sheets were crooked. "The production manager told me, 'The blank looks like a snake,'" recalls the current Bremen site manager. The welding robot could not work with it. But Ruf couldn't send the material back for leveling either. So, together with the customer's employees, he set up an improvised leveling system on site using T-beams and jacks. "We used the jack's pump to push out each shaft individually, 14 hours a day for 10 days. I had to operate the pump by hand - that was one of the most memorable experiences for me," Ruf says. He has been a fierce advocate of flatness ever since.
The EdgeBreaker® 6000 has also brought a whole series of advances for NIRONIT. Although the stainless steel specialist has another deburring machine, it is less precise and requires more maintenance.
Employees must share the quality mindset
There was little effort for the skilled workers in the cutting center. "We selected employees responsible for the systems and had them trained by ARKU," Ruf reports. The two machines are relatively easy to operate, he says, and the control system is also very user-friendly. The training took place over three days during commissioning. Afterwards, the employees were able to work with them themselves. "ARKU has put together a package where the machine does a lot for the operator," explains the site manager. With the EdgeBreaker®, NIRONIT added ARKU's intelligent Wizard software as an option. This was very helpful for Ruf and his team, especially during the training period. This is because the software determines which abrasive belt is the right one for the desired surface finish. It also automatically selects the best deburring tool for the respective machining task. In doing so, the Wizard always optimally adjusts the deburring machine to productivity and tool wear. This means that users can be sure of achieving the desired machining results with minimum effort.
The investment in more quality has paid off for NIRONIT: "Product quality is particularly important to me, because many orders only come back if the quality is right," says Ruf. Many customers don't just want the cut, but a good product, and that creates added value: if the customer has fewer steps in further processing, he is also willing to pay more for it. "The machines from ARKU were once again a good rounding off in the package and perfect for our customer base," sums up the site manager.
