A KR QUANTEC robot depalletizes high stacks of beer crates for Widmer Brothers Brewing

The Craft Brew Alliance (CBA) is an American independent and publicly traded regional brewery. It was created through the merger of the leading breweries along the US Pacific Northwest coast: Widmer Brothers Brewing, Redhook Ale Brewery and Kona Brewing Company

Since then, CBA has offered the beer varieties developed by all three breweries under a single roof. The craft beers from Widmer, the lively Hawaiian island brews from Kona or the brands from Redhook are very popular in the USA and can boast a number of awards. To achieve this, Widmer Brothers Brewing depends on robots from KUKA. A six-axis robot from the KR QUANTEC series is tackling the unloading of beer crates at the beer factory in Portland, Oregon (USA).

Unloading by hand too unsafe, tiring and slow

The previous bottle depalletizer at Widmer Brothers Brewing was a semi-automated system that was no longer able to handle the increasingly shorter cycle times – which slowed depalletizing operations and led to productivity losses. Safety was also a big driver: Unloading the crates by hand was problematic for safety reasons since the motion sequences were repeated. This makes the work extremely tough and very strenuous on the human body. Beyond this, it had to be possible in the future to load the pallets to the full height and not, as was previously the case, just halfway.

Robot depalletizes cases with a vacuum gripper

Since a conventional depalletizer was eliminated as a possibility from the outset due to the low ceiling height, the integrator and official KUKA system partner Midwest Engineered Systems turned to a robot-based solution. The robot had to be able to move the upper layers of the incoming pallet load underneath an existing beam. With its six axes, the KR 270 R2700 ultra selected by Widmer Brewing can easily avoid the ceiling beam and thus unload the pallet stacked to full height.

At Widmer Brothers Brewing, the depalletizing process begins with the fork lift operator. He places a load of bottles on the infeed of the five-zone pallet accumulating conveyor, at the end of which a pneumatic pallet pusher extends, sliding the pallet load across rollers. At the end of the conveyor, the pallet enters the unloading zone of the robot and comes to a halt at the pop-up blade stop, where it is justified parallel to the direction of travel. A pneumatic pallet pusher slides the pallet load over the rollers, thus justifying the pallet in the direction perpendicular to the conveyor flow.

The KR QUANTEC handles the beer cases using a vacuum gripper.

Using a universal vacuum gripper, the KR 270 R2700 ultra robot then positions itself above the top layer of the pallet load, takes the cases there from the pallet, moves to the layer separation conveyor and sets the layer down on the conveyor. The process is repeated multiple times. The layer separation conveyor meanwhile transfers one row at a time onto the case conveyor. The case conveyor pulls the cases away from the layer separation conveyor, ensuring an appropriate gap between the cases.

As the cases travel down the case conveyor, they pass under a checker vision system to determine whether they are aligned with the short or long side leading (and, if necessary, they are turned). The case conveyor then leads in a spiral back towards the robot and upwards to the existing inclined conveyor. As soon as the robot is finished unloading the pallet, the pallet continues down the pallet conveyor, where it is placed in an automated pallet stacker and can be unloaded by a fork lift.

KR 270 scores points with its precision and speed

The KR 270 R2700 ultra performs convincingly at Widmer Brothers Brewing through maximum flexibility and an ideal ratio of payload to reach. It easily lifts 270 kg and has a maximum reach of 2700 mm. Thanks to its six axes, it offers the necessary agility to perfectly master the difficult installation situation due to the low ceiling height. It also scores points for its utmost precision in the loading and unloading operations. As with all robots of the KR QUANTEC series, this model is characterized by up to 160 kg less weight and 25% less volume compared with its predecessor series. The lighter components allow greater dynamic performance and even shorter cycle times, as well as being stiffer than before.

Today, we can deliver all pallet loads for depalletizing at their full height and thus produce at the desired speed. For our 12-packs of beer, this means a hefty increase of 20 percent in productivity

Rick Ginter, Director of Engineering at Widmer Brothers Brewing

Beyond this, cases no longer need to be unloaded by hand. Safety problems – such as employee back strain as well as joint and muscle injuries – have thus been eliminated from this part of the production process.