According to a survey by market research institute Innofact, 94% of Germans consider potato salad to be the barbecue side dish par excellence, even if it is ready-made from the chiller cabinet. Sales increase by up to 300 percent at the start of the barbecue season. Manufacturers such as Wernsing Feinkost have to meet high standards of hygiene design in production. The internationally active food group based in Addrup, Lower Saxony, has been offering potato salad alongside other delicatessen salads and French fries since 1962.

Trapo, a partner for industrial automation in the food industry, ensures precise and clean palletizing of the plastic containers with a high-performance conveyor and robot system. In the selection process, Wernsing was looking for a solution for individual plastic containers of different volumes - from two to five liters. The challenge: precise palletizing in a very small space with an extremely low ceiling height. As all components come from a single source at Trapo, the technology could be individually adapted and programmed to the spatial conditions; a multifunctional gripper takes on two different tasks: Stacking and palletizing.

Optimized conveying, stacking and palletizing
At Wernsing, the potato salad containers are brought together from two lines. With its multifunctional gripper, the robot ensures that the layers are safely stacked on the pallets. The filled containers are then transported via a conveyor belt to the gripper, which in turn places the containers to be stacked centrally and precisely in the recess of the lid of the salad container below.

To do this, the robot grips the containers at an angle and moves precisely to the set-down position. The gripper then gently shakes the layer consisting of four containers and uses this counterforce to gently press the product into the nest of the lower lid. After every two finished layers, vacuum grippers with different levels suck in a single stable intermediate layer at an angle in order to place it precisely. The gripper thus ensures a stable layer pattern with perfectly upright containers. Once the last row has been deposited, an empty pallet is fed via the pallet magazine for re-palletizing.

The conveyor and robot system was designed, manufactured and put to the test at the Trapo technical center in Gescher-Hochmoor. To this end, Wernsing's containers were tested under real-life conditions, quality and performance were checked and data was evaluated in real time. Only food-safe, stainless steel of the highest quality is processed in the in-house production facility - glass bead blasted or electropolished if required. The stainless steel components meet the ever-increasing requirements for use in food production, clean rooms and other sensitive environments. as