Six-axis robot automates sausage production

Kaufland is breaking new ground in processing its 12 kg sausages. The Stäubli six-axis TX200 HE robot now loads the machine to automatically cut 1.5 m long sausages into tasty sausages ready for packaging. This robotic solution relieves workers from repetitive and heavy work and provides many additional benefits.

Robots that come into direct contact with food must meet the strictest hygiene standards. In addition, they must withstand the various disinfection processes and intensive cleaning cycles inherent to the food industry. Still, more and more processors are looking at robotization. "Loading 1,500 mm sausages weighing 12 kg into the slicer during an entire shift was one of the least popular jobs," says Dieter Schäfer, packaging team leader at Kaufland Fleischwaren. "With the introduction of more efficient processes in other parts of production, it also became more difficult to keep up with these manual tasks. Integrating a robot seemed like the right solution, but we were skeptical: would a six-axle machine be able to withstand our cleaning cycles over a longer period of time?"

Reliable under extreme conditions

Martina Düngfelder, head of Life Sciences & Food at Stäubli Robotics Germany dispelled these doubts: "I knew Kaufland's reservations from numerous other projects. But by now our HE (Humid Environment) robots have proven themselves as a benchmark for applications in hygiene-sensitive environments." Stäubli invited Kaufland's senior management to see for themselves during a tour of similar projects and they were immediately convinced. System integrator bsb robot systems gladly took on the project. What initially seemed simple - lifting four giant sausages to a certain position and transferring them to the slicer - turned out to be more complex than expected. Managing director Rainer Bonfig: "The two challenges were fitting the robot into the limited space available and making the gripping technology work with enough precision to handle the sausages without damaging them."

Custom design

The Knaufland slicer is probably the first in the world to be equipped with a six-axis robotic loader. Robot selection was child's play: given the intense disinfection and cleaning processes, only the fully enclosed, waterproof Stäubli HE robot came into consideration. The required payload and range pointed to the large TX200 HE. In designing and constructing the gripper, the bsb team drew on its decades of expertise. To achieve the specified cycle times, four sausages had to be gripped simultaneously. Bonfig explains: "The six-axis TX200 positions the gripper under the four sausages at the transfer position and gently lifts them. The gripper weighs just under 80 kg and is 1,800 mm wide. It has four rollers driven by a central motor for each of the four sausages. The four evenly distributed support points ensure safe lifting and prevent the limp sausages from sagging and splitting." The TX200 approaches the transfer position with high precision before loading begins. Once the final position is reached, the central motor sets the rollers of the gripper in motion. To prevent the sausages from sliding over the gripper, the surface of the 3D printed rollers has a fine spiny surface that provides the necessary traction.

6,000 kg of sliced sausage per shift

With the installation of this globally unique automation system, Kaufland in Heilbronn is now achieving production of 12,000 kg of sliced sausages per day in a two-shift operation. The system processes as many as 21 different types of sausage. These are combined into four different sausage packages. Schäfer: "The Stäubli TX200 HE six-axis robot has completely eliminated my concerns about compliance with our strict hygiene standards. The robotic solution also 100% meets our other objectives. The reduced burden on our employees, the reliable way the machine performs on such a small footprint, the increase in productivity, the high availability, the resistance to intensive cleaning processes and the exciting new possibilities it offers make this project a complete success in every way."

Now in HE version

Meanwhile, the new generation, the TX2-200, is also available in HE version. The TX2-200 HE is the largest robot in the series with a lifting capacity of up to 170 kg and a reach of 2,209 mm, ideally suited for heavier handling applications. At the same time, it is a precise handling machine with impressive dynamics for short cycle times. In terms of food safety, it has the closed structure and smooth contours of its counterpart in the standard version. But as an HE robot, it is compatible with ISO Class 4 environments and fully capable of operating in humid environments (IP67 rating). The enhanced safety technology incorporates all the latest safety features. These comply with SIL3/PLe and thus guarantee maximum safety. The TX2-200 can therefore be used in man-machine cooperation without the need to separate working areas by barriers. The TX2-200 offers a new level of safety, flexibility and user-friendliness, making integration even faster and easier.