At the turn of the 20th century, the valve bag was invented by Adelmer M. Bates, a salesman of salt. The story is that he was selling more salt than his company could deliver, and the filling method of the day seemed to limit his sales commissions.
When you decide to automate your plant’s palletizing process, two categories of palletizers are available: conventional and robotic. Hesitating between those two technologies? Here are the features and benefits of both of them, to help you make the decision that best fits your needs.
Before deciding, make sure you know exactly what your needs are. How many products do you need to handle? What’s the production rate you need to reach? Knowing this information will help you decide whether to go with conventional or robotic. Ultimately, you’re the most informed person when it comes to knowing what your line needs in order to be more optimized.
To select the platform that is best adapted to both current and future needs, it is important to consider five crucial criteria:
Speed | Maintenance | Versatility | Footprint | Price
To identify how the two types of palletizers differ with respect to these criteria, read on.
CONVENTIONAL PALLETIZERS = SPEED
First, let’s look at conventional palletizers, which can be divided into two sub-categories: low level and high level palletizers. A low level palletizer handles products carried by conveyors. Products are aligned or rotated according to the pallets’ configuration. Then, they are pushed against each other to form a row. Then, the row is pushed or lifted by a tool that places the products on the formation table according to the chosen pattern.
The rows are formed, one after another, until a layer is complete. The formation table, now containing a complete product layer, is raised or lowered until the stripper plate is correctly positioned to gently discharge the products onto the pallet. Each layer is created in this manner until the pallet is full. The pallet is then removed, replaced by an empty one, and the process starts over.
With high level palletizers, the products are also brought by a conveyor, but instead of raising or lowering each completed layer for discharge onto a pallet, it is the pallet that is raised or lowered while product layers remain stationary. The high level palletizer can reach higher palletizing speeds and is usually chosen to palletize compressible products, since each layer is compressed on all faces, including its top.
Those differences aside, here are the main features and benefits of conventional palletizers:
- Speed: Conventional palletizers have been developed to adapt to several production speeds. Depending on the model, speed can vary between 10 and 40 bags per minute, but can increase considerably according to the units being palletized (up to 200 cases per minute).
- Maintenance: Due to the number of mechanical operations involved, this palletizer requires more care than a robotic palletizer, but its maintenance demands no specialized knowledge other than traditional mechanics and pneumatics.
- Versatility: Conventional palletizers have been developed to palletize one product type at a time (bags, cases or bales). However, the pallets produced are generally perfect and very compact, since each layer is compressed and squared. With these characteristics, this type of palletizer can produce very high, stable pallets.
- Footprint: A conventional palletizer is a rather imposing piece of equipment that requires considerable space, both on the floor and with regard to height.
- Price: Comparable to that of a robotic palletizer.
ROBOTIC PALLETIZERS = VERSATILITY
Now, let’s talk about robotic palletizers. Obviously, their key element is a robot capable of autonomously performing the tasks assigned by a programmable logic controller. Another crucial component is the gripper (end- of-arm-tool), which is usually customized to handle specific products.
A robotic palletizer can handle one or more units at a time according to pallet configuration, and forms multiple layers on a pallet after picking the products off a conveyor. One of the robotic palletizer’s major assets is its ability to depalletize using a vision system. Here is a summary of its features and benefits:
- Speed: Up to 40 bags a minute, but once again, a robotic palletizer’s speed varies greatly depending on the products being handled. For instance, it can palletize up to 1,200 cans a minute.
- Maintenance: Fewer mechanical components mean much less frequent down time and superior reliability (MTBF estimated: 55,000 hours). However, supervisors need specialized training with regard to maintenance. Premier Tech offers this training upon equipment installation.
- Versatility: Various grippers give the robot great versatility and constitute one of the robotic palletizer’s most important elements. Its specialized end-of-arm tooling can be adapted to almost every need. From vacuum to lateral, finger, and magnetic grippers, they are designed to handle multiple types of containers at a time, regardless of their shape. Also, as mentioned above, the robot is capable of depalletizing many different kinds of containers. Handling multiple infeed of different SKUs on the same line? Vision systems can be used to send information to the robot so it can pick and place different SKUs on different pallets.
- Footprint: The equipment’s dimensions may vary depending on the system’s configuration, but the flexibility it offers allows for installation in tight spaces, while still complying with the most up-to-date safety standards.
- Price: Comparable to that of a conventional palletizer.
There are many advantages to choosing an automated palletizing solution. Among others, companies usually prefer that kind of technology for the increased safety and reduced labor costs it brings.
Automatic palletizers continue to prove profitable for packaging and packing plants. No matter your reasons for considering automating your palletizing process, a thorough evaluation of your needs will be the key to a well- adapted solution.
HYBRID PALLETIZING = BEST OF BOTH WORLDS
And what about combining the strengths of a conventional palletizer with those of a robotic palletizer? If you’re looking for a complete solution that is able to reduce bag overhang on the pallet, the hybrid palletizer is your best option because it combines the advantages of the conventional module with those of the robotic module. The hybrid is designed for flexible packaging (i.e., bags) and automatically positions units of various sizes on a pallet. Hybrid palletizing technology offers consistent squaring and allows palletizing patterns with overlapping units.
Want more information about hybrid palletizing technology? Click here.
Author: Patrick Dargis - Product Coordinator