As a leading steel and metal trader with its own flame-cutting facility in Switzerland, stürmsfs relies on modern production with a high degree of automation. The bevel cutting robot BIBER from ERL Automation GmbH has been used for the automated preparation of components for weld seam preparation since mid-2017. With this, stürmsfs not only achieves significantly better cutting results, but can also significantly reduce production times.
The roots of stürmsfs go back to 1835. Back then, the company was founded as the hardware store Hedinger & Co. In 2001, the name was changed to Stürm AG, before the company merged with the Steel + Metal Division of SFS Locher AG in 2011. This resulted in stürmsfs ag, which is now the largest independent steel and metal trader in Switzerland. In addition to the classic trade in steel and metal products, the company's range of services includes everything from sawing and drilling to grinding and chamfering to oxyfuel and plasma cutting. Fixed cuts in aluminium, steel and stainless steel by one of the most modern sheet metal service centres in Europe round off the range of services. With a total of around 260 employees at its headquarters in Goldach and five other locations in Switzerland, Austria and Slovakia, stürmsfs currently generates an annual sales volume of 100,000 tonnes, 12,000 tonnes from cutting.
Diverse contracts require a flexible solution
Also in the past, a robot system was used at stürmsfs for weld seam preparation. Another part of the components to be processed was manufactured on the two plasma cutting machines with a bevel unit. However, since the previous cutting robot could no longer fully meet today's requirements for modern production, the steel and metal trader decided to purchase a new one.
stürmsfs supplies companies from a wide range of industries, from plant and mechanical engineering to vehicle construction and industrial and residential construction. The orders are correspondingly diverse - a wide variety of chamfers for individual parts, small series or large series have to be handled. "We don't know today what will come next week," says Marcel Meier, Head of Projects / Corporate Development at stürmsfs. That's why flexibility played an important role in the requirements that the company placed on a new system, in addition to a high bevel quality, repeat accuracy and speed.
In the end, a robot solution from ERL Automation convinced the company: stürmsfs decided on a robot cutting system of the type ecoBIBER for oxy-fuel and plasma cutting. In this version, the cutting robot is fixed to a plinth on the hall floor. The robot can process the work area that lies within its reach. Loading and unloading of the cutting station is done from the front. The entire system is monitored by light barriers so that no access is possible in automatic mode.
BIBER simplifies bevel cutting
The automation specialist for welding and cutting technology from Landau a. d. Isar has supplied a system that is suitable for producing bevels of almost any type. Whether single bevels, double bevels, bevels with or without a bridge - the BIBER can be used to apply a wide variety of bevels to already shape-cut parts. For cuts from the top, bevel angles of 30° to 90° are possible, for cuts from the front between 15° and 89°, assuming that the torch is accessible.
Normally, all this is considered to be very time-consuming to prepare and programme. That is not the case with this robot system. The BIBER system from ERL Automation is characterized by simple offline programming and handling. This is also confirmed by Meier: "In just a few steps, the individual part is created in the work preparation, the respective operator calls up the finished cutting programme on the control, places the component or components on the cutting table and then starts the automatic cutting process". Whether series parts, different components or only individual parts are being cut - the BIBER produces bevels with high precision and speed with a short preparation time.
A decisive factor in the accuracy of the BIBER system is that it is equipped with a Kuka KR 60L30HA-ECS industrial robot with a range of around 2,400 mm. This robot is designed for high-precision requirements right down the line. The robot is measured with absolute precision and as a result offers outstanding absolute positioning accuracy. In addition, special gears are used for high path accuracy, which is essential for precise cuts. Thanks to the ECS design, the movements (machine data) are optimized for plasma cutting.
For plasma technology, ERL relies on a HiFocus 360i power source for cutting lengths up to 50 mm. It is equipped with an automatic gas console that mixes the plasma gases optimally for each cutting task – a dedicated database ensures precise control of the required gases. A torch with automatic internal ignition is used for oxy-fuel cutting. This makes cuts of up to 200 mm possible. For both processes, stürmsfs has an integrated cutting database at its disposal, which is based on ERL's many years of experience. By calling up the stored data sets, the process parameters are set automatically – so even inexperienced operators can start part production in just a few steps.
A special feature on the BIBER is the easy exchange of tools. “The tool change can be done comparatively quickly. It takes just five minutes,” reports Meier. This is made possible by a special tool holder that allows plasma and oxy-fuel torches to be changed within a few minutes. The torches can be quickly and easily detached from their respective positions by a screw connection, replaced and reattached at the new position. Plug sockets are available for the cable and signal lines. Automatic torch calibration via a calibrated stop system in the torch holder ensures the correct Tool Center Point (TCP).
A total success
A decisive factor in the decision to invest in the BIBER cutting robot was a reference visit to a company that uses a similar system from ERL in its production. The BIBER in practice as well as the experience of the well-known mobile crane manufacturer with regard to availability and flexibility ultimately convinced the Swiss steel and metal trader.
The people responsible at stürmsfs have not regretted this decision. "From planning to assembly to operation, we are completely satisfied with the BIBER. With the cutting robot, we have significantly strengthened our competitiveness in the field of weld seam preparation, not only because we achieve much more accurate results, but also produce bevels three times faster than with our previous robot system," Meier sums up. With the ecoBIBER, however, stürmsfs not only shortens its production times. Thanks to the wide range of possibilities in weld seam preparation on the new cutting robot, the gantry cutting systems that are sometimes used for bevel cutting are also relieved.
Further concrete collaborative projects are not planned at the moment, he said, but based on the very positive experience stürmsfs has had with ERL, a continuation of the collaboration would be quite conceivable. "You should never say never," says Meier. If the demand for bevel parts increases, a switch to the next larger BIBER variant profiBIBER cannot be ruled out, he added.



