In good partnership to the perfect surface
Robot-assisted grinding system from SHL in cooperation with 3M and FerRobotics delivers convincing results at stove manufacturer HASE

The customers of HASE Kaminofenbau GmbH also attach particular importance to the exterior - after all, the stoves should not only be warm, but also cut a fine figure in the domestic ambience. Accordingly, the stove manufacturer based in Trier focuses on the flawless finish of the steel components. HASE is supported in this by SHL AG from the Swabian town of Böttingen. Together with project partners 3M and FerRobotics, the specialists have developed a robot-assisted grinding system that fully meets the stove manufacturer's high expectations in terms of surface quality and process reliability.


Böttingen, 01.03.2021 - It all started just over 40 years ago. The pioneer of HASE stoves was the architect Walter Blasius. In the mid-1970s, he built the first HASE for his home because he couldn't find a stove that met his expectations. This one was so well received by family and friends that he founded HASE Kaminofenbau. Other models followed. "We have developed step by step and today focus on high-quality stoves with an appealing design," outlines Elmar Willems Production Developer at HASE. The second-generation family-run company invests heavily in modern technology and continuously improves its production processes. Depending on seasonal workload, the company employs up to 180 people, including 20 apprentices. "We like to recruit our staff from our own ranks and thus counteract the shortage of skilled workers," says Elmar Willems.

The Trier-based company is particularly proud of the high level of vertical integration in its five production halls. HASE has its own ceramic production facility and manufactures the furnace lining in-house. A large development department researches efficient products. Every year, two new models are designed and older ones are taken out of the program. HASE has 25 different models in its portfolio at all times, and between 12,000 and 14,000 stoves are produced each year. The main markets are Germany, France and Switzerland, but the company also exports worldwide. Sales are handled exclusively by specialized dealers.

High demands on grinding technology
Grinding technology plays a particularly important role. "We have very high demands on surface quality and design. Edges, for example, must be perfectly rounded," describes Elmar Willems. HASE uses a high-temperature paint as a coating, which is applied in a thickness of 25 micrometers. This must withstand temperatures of up to 600 degrees Celsius without discoloring. "On this inorganic coating, the smallest defect is visible, so the grinding must be perfect," says Willems. Until now, this has been done manually - with HASE dealing with an increasingly pressing problem. "We can't find personnel willing to grind eight hours a day. This work is as demanding as it is costly," Willems knows. So the furnace manufacturers looked around the world of automated grinding technology for a possible alternative.

The experts discovered a first starting point at a trade show. Among other things, equipment from FerRobotics was on display there. "That could work," Elmar Willems thought to himself, and finally made contact - with clear objectives. The first task was to grind a steel furnace door, in top quality and with one hundred percent process reliability. Thomas Magnussen, Head of Sales & Marketing, and Markus Merkel, Project Manager, both from SHL, took on these challenges after being contacted by their partner. "We saw opportunities here," Magnussen summarizes. A short time later, SHL employees were on site to take stock and analyze the processes. "At first, I couldn't imagine that a robot could manage this task," says Elmar Willems with a smile. But a short time later, a system was set up at the development center in Böttingen, and the test results on original components convinced the furnace builders from Trier all along the line.

Sensitive contact flange
SHL was assisted in this project by two experienced partners: abrasives manufacturer 3M and FerRobotics Compliant Robot Technology GmbH. The latter is a start-up from Linz in Upper Austria. "Our first product was a robot that works similarly to a human hand. Since 2010, we have been on the market with an active contact flange that fits on any commercially available robot. In recent years, we have developed additional complete solutions such as the Active Orbital Kit, which is also used at HASE. This active grinding head compensates for tolerances and always works with the correct contact force on the surface," describes Key Account Manager Harald Gschnaidtner. Contacts with SHL have existed for years, and the automation specialists have had good experience with FerRobotics' industrial grinding tools. "Synergies have been successfully implemented here. To create a perfect surface, tolerances in the millimeter range must be compensated. This requires a functioning control loop, and the Active Compliant Technology ACT from FerRobotics handles this without any problems," Thomas Magnussen summarizes.

The third partner on board is 3M Deutschland GmbH. The abrasives manufacturer has been working intensively with SHL since 2018 and itself operates a robot cell from the grinding specialist in the training center at the Neuss site. "We are on hand to provide advice and support on surface design," says Thomas Hillebrandt, Business Development Specialist at 3M. High-performance Cubitron II abrasive belts are used in the Trier facility. These are fitted with ceramic abrasive grains in a defined geometric shape. The tips of the triangles break during the process and new, sharp geometries are created along the specified chip edges. The surface of the material is cleanly machined by these tips. This provides fast, cool grinding and extended abrasive life.

System works smoothly
The grinding solution from SHL and its partners has fully met expectations at HASE and is operating smoothly. The welded furnace doors are delivered to the plant. An employee inserts the components and closes the safety door. The robotic arm grips the component and guides it to the SHL type DKS double friction and contact roller grinding machine. "There, the basic machining is done first. In the subsequent eccentric sanding, the structures are broken to obtain a homogeneous sanding pattern," describes project manager Markus Merkel. The robot then moves the door to the FerRobotics unit where the finish is applied. It is then deposited in a defined manner. 

With the commissioning of the automation solution, the processes have improved significantly and the problem of manual grinding has been eliminated. "The system runs to our complete satisfaction, and we reliably achieve the required top surface," Elmar Willems summarizes. He is also completely satisfied with the processing time. In addition, the quality of the cooperation plays an important role for him. "Obtaining perfect surfaces for our components in an automated way is only possible with a highly qualified partner," he says, and does not spare praise: he describes the cooperation with SHL as impeccable. "One call is all it takes and things are running smoothly again."

From SHL's point of view, the cooperation with project partners 3M and FerRobotics was also a successful symbiosis. Markus Merkel: "It was a constant give and take, and we always worked constructively on solutions. The cogs have successfully interlocked." The decision in favor of the SHL system was a first step for Hase to automate grinding processes. Elmar Willems is already thinking ahead. Currently, the company is building jigs and writing programs - with a clear goal: "In the future, we would like to machine all exterior cladding on this system."