Robotized solutions for palletizing are becoming increasingly common in a variety of industries that handle packages such as cartons, boxes, boards and details or bulk materials such as building materials, grain, seeds, fodder, chemicals and fertilizers. Having in mind, the regulatory requirements related to heavy lifting by humans, it is a far better decision to use a robot for this process that can lift and place weights on a pallet with speed and precision, 24/7.

In our experience, the investments in robot palletizing offer very high returns on investment (ROI) because it decreases significantly the labour costs. It is common for such investment to offer ROI from 25% to 50% on an annual basis. Moreover, since the palletization is usually at the end of the production process, the increased palletizing speed could potentially remove a bottleneck for the whole production. In this case, the investment has a huge immediate impact on the throughput and consequently on sales and cash flow. Then the ROI of such a project could be even higher.

In some cases when the production process upstream of the palletization is optimized and its capacity increased, the robot palletizing itself could become a bottleneck for the whole production. An obvious solution would be to add more palletizing robots. However, this is a significant investment, and sometimes it is not even feasible as the free floor space is limited. In such cases, it is better to investigate if the work of the existing robots could be optimized.  In the following article, we will highlight one such project.

Our customer needed to increase the palletizing capacity of his Fanuc robot as he has added new production capacity upstream of it. As a result, the palletizing robot has become a serious bottleneck for the whole production. Adding a second robot was possible, but the not preferable solution as the production floor space is very limited.  We analyzed the way the existing robot works and we found out that it is possible to optimize it so that its palletizing capacity would be greater than the production capacity of the upstream production.  We implemented several interrelated improvements:

• First, we organized buffering by introducing intelligent management of the conveyor belts. In the previous configuration, there was no buffer between the robot and the intermediate upstream operation – the bag filling. If the robot could not handle fast enough the palletization, the bag filling was becoming blocked and had to stop working. With the new buffer, we eliminated the blockage of the filling machine during technological downtime of the robot, for example when the full pallet was being replaced by an empty one. Notice on the video below, how the bags are lined up in front of the robot while the pallet is changing. When the second improvement described below was introduced, the robot is fast enough to compensate for the delay and exhaust the buffer. This measure alone increased the throughput by approximately 30%.
• Second, the speed of the robot was limited due to incorrect robot movement, exacerbated by the existing gripper’s gripper design. As a result, at greater speeds, the robot was dropping and sometimes tearing bags. We engineered and manufactured a new gripper, Siviko PBGT1, which has a better grip on the bags and allows for greater movement speeds. We also preprogrammed the robot and optimized its movements. This increased the palletizing speed and throughput by an additional 50%.

• The third step was to integrate the robot with the existing SCADA system that we have built on Ignition by Inductive Automation. Now the operators could easily change the palletization program of the robot in the same user-friendly interface. This eliminated undue idleness.

In the following video, you can see by yourself what the effect of optimization is. On the left side is the robot after the transportation system has already been optimized. On the right side is the robots after all improvement have been implemented. In this case, the robot is palletizing bags from two production lines so that its new capacity could be utilized.

Optimizing the work of the existing equipment or investment in new equipment is always a question that the management should consider. It saves money, time and space. If the palletization is a bottleneck, are you sure whether your palletizing robots working to their full capacity?