Robot
Automation
How many cases per minute can a palletizing robot really handle?
A palletizing robot handles between 4 and 7.5 picks per minute, depending on the cell. This range comes from the published cycle times of current palletizing cells such as the MalocherBot models, rated at 8 to 15 seconds per cycle. How many cases per minute that turns into on your floor depends on the gripper, the pallet pattern and the time lost in between. A field example: the palletizing cell at Seeberger handles up to 5 cases per minute.
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The short answer: there is no single number
Vendors rate palletizing cells by their cycle time. The MalocherBot models, for example, are rated at 8 to 15 seconds per cycle, which works out to 4 to 7.5 picks per minute. The actual throughput sits below that figure, because throughput is not a property of the robot but the outcome of the entire process. The same palletizing robot handles half as many cases per minute with a single pick as it does with a double pick.
Vendor speed ratings almost always refer to cycle time under ideal conditions: a defined case, a known pallet pattern, no slip sheets, no pallet changeover. That figure is useful for comparing cells. As a forecast for your line, it only goes so far.
The throughput of a palletizing cell is cycle time times pick quantity minus auxiliary time. The case, the gripper, the pallet pattern, slip sheets and the pallet changeover decide how far the real rate falls below the calculated maximum.
How to calculate palletizing throughput
A palletizing cycle consists of 4 steps: pick the case, travel to the target position, place it, travel back. The cycle time is the duration of this sequence. The calculated maximum rate follows from it: 60 seconds divided by the cycle time equals the picks per minute.
Two examples based on published cycle times. A cell with 15 seconds per cycle calculates to 4 picks per minute. A cell with 8 seconds reaches 7.5 picks. If the cell picks one case per cycle, picks equal cases. If it picks 2 cases at once, the calculated rate doubles.
The formula shows where the levers of a palletizing robot sit. You shorten the cycle time with shorter travel paths and higher speed. You raise the pick quantity with a gripper that takes more than one case per cycle. The auxiliary times outside the formula decide how much of the maximum rate remains at the end of a shift.
5 factors that determine real throughput
5 factors set the gap between the real and the calculated rate:
| Factor | Effect on throughput |
|---|---|
| Case | Weight, size and surface limit gripping speed and pick quantity |
| Gripper | Single pick or multi-pick multiplies the rate per cycle by the pick quantity |
| Pallet pattern and stacking height | Long travel paths to the top layer cost seconds per cycle |
| Slip sheets | Every inserted layer is an additional handling step without a case |
| Pallet changeover | Manual changeover creates idle time, a magazine or conveyor changes pallets in cycle |
Case and surface set the physical limits. A 6 kg case moves faster than a 10 kg case. A coated surface holds on a suction gripper more reliably than porous corrugated board, and an unstable case forces slower acceleration.
The gripper is the biggest throughput lever. Vacuum area grippers with separately controlled suction zones pick up 2 or more cases per cycle, provided the infeed and the pallet pattern allow it. A multi-pick with 2 cases doubles the calculated rate without the robot moving any faster.
Pallet pattern and stacking height determine the travel paths. An interlocked layer pattern needs more placement moves than a simple column stack. The taller the stack, the longer the path. Cells with a stacking height of 2.2 m travel the longest paths on the last layer.
Slip sheets cost pure auxiliary time. Each slip sheet is a separator layer of cardboard or plastic between 2 layers. It has to be picked, moved and placed without putting a case on the pallet. If you need slip sheets, account for their handling with its own cycles in the throughput calculation.
The pallet changeover decides the idle time per hour. If an operator pulls the full pallet and inserts an empty one, the cell stops at every change. A pallet magazine or pallet conveyor performs the change without losing a cycle. This is exactly where a semi-automatic cell separates from a fully automatic line at the end of the packaging line.
The bottleneck of a palletizing line often sits in the pallet changeover or the case infeed, not in the robot. The throughput of a line is always set by its slowest element.
Field example: five cases per minute at Seeberger
At Seeberger in Ulm, a MalocherBot cell palletizes up to 5 cases per minute and up to 6 pallets per hour, running three shifts. The shipping cases weigh 6 to 10 kg. Seeberger produces nuts and dried fruit.
The technical setup is the MalocherBot PAL M system platform. The robot is a KR20 from the manufacturer KUKA, the gripper a vacuum area gripper from Schmalz. The gripper covers all case sizes on site with a single tool, so no tool change is needed. Operators change case type and pallet pattern through the control software LUNA (LUNA Automation OS), without external programming.
Measured in live operation, the 5 cases per minute sit below the cell's calculated maximum rate. The figure comes from real cases, a real pattern and real auxiliary times, not from a datasheet. Details of the project are in the Seeberger case study.
When a cobot is enough and when you need an industrial robot
The choice between a cobot and an industrial robot follows from 3 figures: target rate, payload and reach. A collaborative robot, in short a cobot, works without a safety fence, needs little floor space and adapts flexibly. In return it works more slowly and carries less. An industrial robot reaches shorter cycle times, higher payloads and longer reach, but requires safeguarding and more space.
The decision follows from 3 figures of your application:
- Target rate. If you need a few cases per minute, a cobot palletizer is usually sufficient. If the cell has to close out a fast packaging line, the route leads to an industrial robot.
- Payload and case weight. Heavy cases or a multi-pick with 2 cases per cycle quickly add up to values that exceed a cobot's payload capacity.
- Stacking height and pallet size. Tall stacks on EUR (Euro) or ISO pallets demand a reach that smaller cobots do not provide.
Since the 2025 revision of the robotics standard ISO 10218, the standard assesses the application, not the product category. A cobot moving heavy cases at speed is not automatically the safe solution just because it is sold as collaborative. The risk assessment decides. The general strengths and limits of the cobot design are summarized in the article on the advantages and disadvantages of cobots.
How to verify a vendor's throughput claim
Throughput claims in a quotation become comparable once the boundary conditions match. 5 questions make a claim testable:
- Which case was measured? The weight, size and surface of the test case must match your case, otherwise the figure does not transfer.
- Single pick or multi-pick? A rating of 8 cases per minute can come from 4 cycles with a double pick. Whether your pallet pattern allows a multi-pick is a separate question.
- Is the pallet changeover included? The rate with conveyor-based changeover and the rate with manual changeover differ noticeably across a shift.
- Does the figure hold for your stacking height? A rate measured at half height does not apply to the last layer at 2.2 m.
- Is there a field test with your cases? Serious vendors test with the customer's sample cases before committing to a throughput.
These 5 verification questions belong in the same category as the other points of project planning. The mistakes that repeat alongside them are covered in the article on common mistakes when planning a palletizing project.
Which throughput class fits your application and what the cells cost is shown on the product page of the palletizer from Unchained Robotics. Cycle times, payloads and prices are listed openly. How fast a cell pays back at your case volume is shown by the calculator for return on investment (ROI), using your own figures.
Frequently asked questions
What is the difference between cycle time and throughput?
The cycle time is the duration of a single palletizing cycle from picking to placing a case. Throughput is the output over time: pick quantity per cycle divided by the cycle time. All auxiliary times such as pallet changeover or slip sheets reduce it.
How many cases per minute can a cobot palletizer handle?
There is no universal figure here either. Because of their limited speed and payload, cobot palletizers sit in the lower throughput range and suit applications with a few cases per minute. For higher rates, industrial robots are the standard choice.
What is a multi-pick in palletizing?
With a multi-pick, the gripper takes 2 or more cases at once and places them in a single cycle. The multi-pick multiplies the calculated palletizing rate by the pick quantity, a doubling with 2 cases. It requires a suitable case infeed and a pallet pattern that accepts 2 cases side by side.
How much does the pallet changeover slow the cell down?
That depends on how the change happens. A manual changeover creates idle time with every full pallet. A pallet magazine or pallet conveyor performs the change without losing a cycle. Across a shift, the difference adds up to a noticeable share of total output.
How many pallets per hour are realistic?
The pallet count depends on the case rate and the cases per pallet. The palletizing cell at Seeberger reaches up to 6 pallets per hour at 5 cases per minute. To get more pallets per hour, you need to raise the case rate.
Is a palletizing robot worth it with frequently changing case formats?
Yes, provided the changeover works without external programming. With systems like the MalocherBot, operators change case sizes and pallet patterns themselves through the LUNA software. What matters is that the new format stays within the limits of the gripper and the cell.