A packaging manufacturer of paperboard cartons and corrugated containers was continuing their efforts to reduce labor costs with automation. They have purchased robotic palletizers from Flexicell for two lines, one palletizing shrink-wrapped bundles and the other palletizing open-top cases. These systems have proven to be a great success in reducing labor, increasing the consistency of pallet loads, and functioning at a higher operational efficiency.
The packaging manufacturer wanted to automate the palletization of a production line responsible for both loose and bundled stacks of cartons. The loose stacks could shift out of alignment, making them prone to damage. A wide range of carton sizes and configurations ran on this line. In addition to furthering their goal in containing labor costs, the manufacturer needed a solution that would reduce waste due to product damage while handling the varying package dimensions.
Since the application was significantly different than the others, a new design was needed. The manufacturer entrusted Flexicell with the new project because of the prior projects successfully implemented by Flexicell.
Palletizing Automation Reduces Labor and Increases Accuracy
The solution designed by Flexicell incorporated a stack straightening mechanism to eliminate shifting. Then a robot accurately handles the stacks with a firm but gentle grip that prevents shifting during placement.
To prepare the palletizing system, the operator loads the pallet magazine, tier sheet magazine, and slip sheet magazine, and then selects the product being run on the human-machine interface (HMI). The HMI consists of an Allen-Bradley Panelview Plus 600, chosen because the plant personnel are familiar with its functionality.
After the system begins to run, pallets in stacks of 10 are conveyed into the robot’s workspace, or “cell”. The robot, a KUKA KR 150 L110 model, automatically picks a pallet from the top and places it in the loading zone. The loading zone consists of a conveyor that will later transfer the pallet load to the fork-lift truck pick-up area. A slip sheet is taken from the slip sheet magazine by the robot and placed on the pallet.
The stacks of cartons convey single-file into the cell on the infeed conveyor. Shrink-wrapped bundles are palletized one at a time. Loose stacks are realigned using a stack straightener. The stack straightener lifts each loose stack of cartons off the conveyor and adjusts them with gentle pressure, ensuring the stack is uniform. After straightening, the loose stacks are presented to the robot and palletized.
The palletizing robot is equipped with a versatile end of arm tool (EOAT) to handle the carton blank stacks. The EOAT features a set of servo-powered
pneumatic forks and clamps that adjust according to carton size. When picking the stacks of cartons the robot positions the forks underneath while the clamps hold from above. The EOAT also features hooks to pick and place pallets, along with vacuum grippers to pick slip and tier sheets.
When each layer is complete, the robot picks a tier sheet from the tier sheet magazine and places it on top of the layer. After a pallet load is complete the pallet conveyor transfers it from the loading zone to the fork-lift truck pick-up area.
The Flexicell robotic palletizer is capable of handling stacks that vary in width, height, and weight. If a new carton is introduced to the line, the palletizing system can be updated by the trained staff at the plant—or by Flexicell’s service technicians. The flexibility of the system saved the packaging manufacturer from the hidden costs in semi-automatic and manual systems. Using one robot for both products, and the other functions of the palletizer, also kept costs down.
After implementation the manufacturer saw a reduction in labor costs and product loss. Learn more about our palletizing systems on our website. Contact us if you would like to see how we would provide you with similar results.