140 percent more productivity

With the help of the lightweight gripper SLG from Schmalz, the robot reliably removes the punched sheets from the stack one by one. © Lard
With the help of the lightweight gripper SLG from Schmalz, the robot reliably removes the punched sheets from the stack one by one. © Lard

For Lang Metallwarenproduktion Neubrandenburg, the investment in an automation solution is paying off: The individual lightweight gripper SLG from Schmalz handles stamped and bent parts quickly and reliably, thus significantly increasing productivity. The elimination of cumbersome manual tasks also means greater safety in the workplace.

Jörg Monsig, plant manager at Lang Metallwarenproduktion Neubrandenburg GmbH, is looking for the weak points. The aim is to optimize production in order to remain competitive and an attractive employer. “We want to create modern, intelligent and connected workplaces,” Monsig explains. As early as 2013, he introduced a company health management system and optimized various work processes according to ergonomic aspects. Now the task was to automate the assembly of a spot welding system and thus increase productivity and workplace safety.

Lang Metallwarenproduktion Neubrandenburg GmbH can look back on a long tradition: the parent company, Lang und Vertriebs GmbH, based in Munich, has been manufacturing and assembling stamped and drawn parts for over 60 years. The start was made by components made of chrome for the automotive industry. In 1992, the company moved into new production premises at the Woldegk site in southeastern Mecklenburg-Vorpommern and founded Lang Metallwarenproduktion Neubrandenburg GmbH. Today, the approximately 50 employees produce stamped and drawn parts mainly for the automotive industry – from stainless steel and all common metals in small quantities up to large series.

Despite limited gripping surfaces on the bent die-cut part, the robot works very reliably with the SLG gripper. © Lard
Despite limited gripping surfaces on the bent die-cut part, the robot works very reliably with the SLG gripper.
© Lard

Clear handling requirements

“We always look to see where we can avoid monotonous manual tasks,” Jörg Monsig tells us, pointing to a yellow robot separated by a protective fence. The robot picks up sheet metal parts from a turret table. Until six months ago, a worker stood here. He took a stamped and bent part, fitted it to the spot welding machine, which joined it to an automatically fed nut. After joining, he checked the joint. “Monotonous work tends to lead to a higher reject rate,” the plant manager points out. What also bothered him was that only one person could work on the system, which limited the output.

Those responsible from Woldegk wanted to change that and directly started an R&D project with the support of the European Regional Development Fund. Their automation requirements: “A robot was to pick up the components from above and separate them. For this, we needed a gripper that enables high cycle times and can accelerate to five meters per square second,” says Monsig.
A mechanical gripper solution proved to be a technical dead end: It would fail when it came to separating the thin stamped and bent parts measuring 150 x 150 millimeters and weighing 500 grams. A pneumatic variant would face completely different challenges: The gripping surfaces are limited due to engravings, holes and the three-dimensional geometry and lie in different planes. “An off-the-shelf solution seemed difficult to us,” describes the plant manager.

But not for the vacuum experts at J. Schmalz GmbH: “Jörg Monsig and his team need a gripper for robotic automation that is specially tailored to the particular geometry of the sheet metal parts,” recalls Dr. Florian Fritz, Head of Business Development Process Vacuum Systems at Schmalz. For the vacuum experts, the solution was therefore obvious: The lightweight gripper SLG can be individually adapted to the sheet metal parts – without any design or manufacturing effort for the user. Using the STL file of the bending die-cut part, Monsig was able to configure the gripper online and assemble it just a few days later. “In order for us to deliver individually designed and automatically constructed grippers in such a short time, we use 3D printers. Additive manufacturing technology not only reduces weight, but also interfering contours, as the air guide is integrated right into the end-of-arm tool, eliminating the need for a separate hose guide,” explains Dr. Fritz.

Economical operation was also crucial: The gripper holds the component for a long time – during pickup, during the welding process and the quality check until it is put down. “The SCPSi compact ejector meets these requirements with flying colors,” emphasizes Dr. Fritz, adding, “Thanks to its eco nozzle technology, the SCPSi achieves a high suction capacity with minimized compressed air consumption. This can be reduced by up to 80 percent thanks to the integrated air-saving function.”

The automation solution moved, joined and tested 180,000 components within six months. © Lard
The automation solution moved, joined and tested 180,000 components within six months.
© Lard

Material flow optimized

The new plant has enabled the automotive supplier to optimize its material flow. An employee stacks the bent stampings on the turret turntable while standing at a safe distance from the robot and the automatic welder outside the safety fence. The robot picks up the parts one by one from the table and holds them in the spot welding machine. Piece by piece, the table lifts the stack so that the robot can always remove the component from the same position. The welding gun closes and joins an automatically fed nut to the bending blank by means of resistance spot welding. The robot holds the component securely during the process and then guides it in front of a camera that checks the correct connection. He then drops the component onto a conveyor belt.

Safe and more efficient

Lang Metallwarenproduktion benefits from the Schmalz solution in several ways: “Our productivity has improved by 140 percent,” describes Jörg Monsig. In addition, process reliability has increased significantly. “The system runs without any problems. Within six months, we have welded 180,000 components without any malfunction.” The employees have also accepted the facility very well. “We were able to clearly improve the working conditions and the activity has become safer. Cumbersome manual tasks have been eliminated, and the performance of all the people involved has increased – an important aspect in view of demographic change. We are very satisfied with this solution,” Monsig sums up. There is also much praise for Schmalz’s service. “The delivery was made only a few days after the order and the system was quickly installed on site. Afterwards, we went straight through.”

About the company
Schmalz is a leading internal national company in automation with vacuum as well as for ergonomic handling systems. Schmalz products are used in logistics applications as well as in the automotive industry, the electronics sector or furniture production. The broad spectrum in the Vacuum Automation business area includes individual components such as suction pads or vacuum generators, complete gripping systems and clamping solutions for holding workpieces, for example on CNC machining centers. In the Handling business segment, Schmalz offers innovative handling solutions for industry and trade with vacuum lifters and crane systems.

With the Energy Storage business area, the company is establishing a further mainstay in the field of stationary energy storage. The combination of comprehensive consulting, high innovation orientation and first-class quality ensures customers sustainable added value. Intelligent solutions from Schmalz make production and logistics processes more flexible and efficient – and at the same time fit for advancing digitalization.

Schmalz is represented in all major markets with its own locations and trading partners in more than 80 countries. The family-owned company employs around 1,500 people at its German headquarters (Glatten, Black Forest) and in 21 other companies worldwide.