Bottlenecks on a packaging line aren’t always caused by a slow machine, but rather by a lack of synchronization between filling, capping, conveying, and labeling. Discover how a fully automated line can improve production flow, reduce downtime, and make better use of installed capacity.
On a packaging line, a faster machine doesn’t always mean faster production.
A filling machine can operate at a high rate, but if the capping or labeling machine cannot keep up with that same throughput, the result will not be increased productivity. Backups, delays, micro-stops, and constant adjustments will occur, reducing the facility’s actual capacity.
This issue is particularly relevant in industries such as cosmetics and chemicals, where a single plant may handle products with varying viscosities, numerous packaging formats, different types of closures, and multiple labeling configurations.
That is why, when seeking to improve productivity, it is not enough to analyze each machine individually.
We need to analyze how the entire line works.
Why do bottlenecks occur on a packaging line?
A bottleneck occurs when one phase of the process has less capacity or takes longer than the preceding phases.
The simplest example is a filling machine that operates faster than the labeling machine.
As long as there is free space on the conveyor between the two machines, the difference may go unnoticed. But little by little, the containers begin to pile up in front of the labeling station.
When the accumulation reaches the available limit, the previous stage must slow down or stop.
The cycle can be repeated many times during a shift:
production → accumulation → stoppage → standby → restart.
The problem isn’t necessarily that any of the machines are malfunctioning.
It may be the case that all of them are working properly, and yet the line is out of balance.
Desynchronization between machines is a source of downtime
When the filler, capper, and labeler operate as independent units, each one primarily follows its own parameters.
This can lead to various situations:
-
One machine is waiting for product while another is at full capacity
-
Containers pile up between stations
-
Operators have to step in to get the flow moving again
-
There are continuous starts and stops
-
The conveyor ends up serving as nothing more than a temporary storage area
-
The gap between theoretical and actual production is widening.
Micro-stops are particularly difficult to detect because many last only a few seconds. However, when they occur repeatedly throughout a shift, they can result in a significant loss of productivity.
In terms of OEE ( Overall Equipment Effectiveness), these minor interruptions and slowdowns directly affect the line’s actual performance and can mask a significant portion of unproductive capacity.
The problem isn’t solved by making all the machines faster
A common response to a bottleneck is to try to increase the speed of the machine that appears to be limiting production.
But it isn’t always the best solution.
If a labeling machine operates more slowly than a filling machine, increasing its speed may temporarily improve the situation. However, this may also shift the problem to the capping machine, to a subsequent station, or to the conveyor between machines.
The goal shouldn’t be to have every team constantly working at its maximum speed.
The goal should be for the entire line to maintain a stable and coordinated production flow.
In other words, it’s not about optimizing individual machines. It’s about optimizing the entire process.
How does integrating a production line help?
An integrated workflow connects the various stages of the process so that they do not operate as isolated elements.
Filling, capping, transport, and labeling become part of a single production system.
Both the hardware and the control system play a role in achieving this.
1. Sensors that detect what is happening
Sensors provide real-time information on situations such as:
-
presence or absence of packaging
-
backups at certain points
-
availability of space downstream
-
arrival of the container at a station
-
the need to stop or resume the flow
-
certain process alarms.
This information allows the system to react before a traffic jam occurs. It can anticipate it.
2. The control system coordinates the various stages
The information collected by the sensors is used to manage the line’s operation.
If a backlog begins to build up before the labeling machine, for example, the system can temporarily reduce or stop the feed from the preceding stages.
When there is once again enough space, the flow can resume.
In this way, the line adapts to the actual status of the process.
Instead of functioning as three separate machines, it begins to behave as a single, coordinated system.
Today’s industrial automation architectures use controllers, field signals, variable-speed drives, actuators, and industrial communications to coordinate machines and facilitate the monitoring of the entire system.
3. The Role of Conveyors and Accumulation Zones
In an integrated production line, conveyors are used for more than just moving containers.
They also help regulate the flow between machines that don’t always operate at exactly the same pace.
A properly sized accumulation zone can accommodate small speed variations without requiring the entire line to be shut down immediately.
But it’s important to understand one difference:
A temporary buildup can help balance production; a constant buildup indicates that there is a bottleneck.
If one machine consistently produces output faster than the next one can process it, extending the conveyor belt will only delay the onset of the problem.
That is why the design of the line must take the following factors into account together:
-
speed of each station
-
storage capacity
-
transportation
-
control logic
-
product type
-
package size
-
reference change frequency.
4. An integrated system also improves the information available
Another benefit of integration is that it provides a clearer view of the process.
Operator interfaces allow you to control parameters, view statuses, and detect issues more quickly.
In a facility consisting of completely independent pieces of equipment, a malfunction may require the operator to check several machines to pinpoint the source of the problem.
As part of a coordinated effort, process information helps us understand what is happening and where the disruption is occurring.
For Production, this makes day-to-day operations easier.
For management, it improves the ability to identify where time and productive capacity are being wasted.
The Economic Impact of the Bottleneck
Every minute that a production line fails to produce as it should comes at a cost. And that cost isn’t limited to labor. It can also include:
-
production that does not take place
-
overtime to catch up on orders
-
energy consumed without useful output
-
shortages or rework
-
maintenance work
-
time spent by staff resolving incidents
-
less efficient use of the investment made in machinery.
That’s why it’s helpful to calculate the cost of downtime in a simple way:
Cost of downtime = downtime × cost per hour of production
Other costs directly related to the shutdown—such as waste, overtime, or maintenance—can be added to that figure.
You don’t need to use complex financial models to identify opportunities for improvement.
In many plants, it is sufficient to compare the production that should have been achieved during a shift with the production actually achieved and analyze which part of the difference is due to downtime, delays, or imbalances among machines.
Example of How to Identify Bottlenecks
Let’s imagine a production line where the filler can operate at a speed that is clearly faster than that of the labeling machine.
During the shift, the filling machine stops periodically because containers build up before the labeling station.
Each stop is brief. But when you add them all up, they can end up accounting for a significant portion of the workday.
In this case, further increasing the filling capacity would offer virtually no benefit.
The investment would make more sense if it were used to balance and integrate the entire line.
That is the principle that should guide the calculation of ROI:
Not how much a machine produces, but how much more the entire production line can produce after eliminating its losses.
Less downtime means lower costs
A synchronized production line can help reduce operating costs (OPEX) because it makes better use of existing resources.
If more compliant containers are produced during the same shift using a similar amount of labor, energy, and facilities, the operating cost per unit decreases.
In addition, a more stable flow can reduce:
-
manual intervention
-
unnecessary stops
-
overtime
-
waste
-
reprocesses
-
wait times
-
lost production.
For management, this is one of the most important factors to consider when evaluating an automated line.
An investment should not be evaluated solely based on its purchase price.
It should be compared to the cost of maintaining the current inefficiencies for years to come.
From individual machines to a complete MarCoPack line
When production problems stem from the interaction between several workstations, the solution must also be approached as a whole.
MarCoPack designs and manufactures complete automatic filling, capping, and labeling lines, tailored to the characteristics of the facility, the product, and production needs.
Their lines typically include:
Filling → Capping → Labeling
along with the transportation components and other complementary solutions required for each project.
MarCoPack designs custom lines tailored to each production facility that can be configured in a linear, L-shaped, U-shaped, or compact layout, and are designed to handle a variety of liquid products—whether fluid or dense, foaming or non-foaming—as well as different container formats.
This is particularly relevant for cosmetics and chemical manufacturers, where a single facility may need to accommodate a wide variety of products, containers, and closure systems.
1. Filling tailored to the product
MarCoPack’s automatic and semi-automatic filling machines offer a wide range of options, such as volumetric dosing or dosing via flow meters, and can be adapted to different formats and configurations with various filling nozzles depending on production needs.
2. Cover integrated into the flow
MarCoPack’s automatic capping machine is part of the same production line and can be configured for different closure systems.
Integrating it into the overall design allows us to take into account the required speed and its relationship to filling and labeling from the very beginning.
3. Labeling as part of the production line, not as a standalone process
The labeling phase must be sized based on the actual throughput of the entire system and the characteristics of the containers.
MarCoPack offers solutions for various labeling positions and configurations. Our catalog of labeling machines includes positioning control features, alarms, and real-time average production calculation capabilities in certain configurations.
Design of Complete Production Lines
Designing a complete line from the ground up changes the outcome, and the biggest difference becomes apparent during the design phase. When each machine is selected independently, it is more likely that incompatibilities in speed, conveyance, format, or operation will arise later on.
When the installation is planned as a complete line, it is possible to analyze the following from the outset:
-
What will be the target cadence?
-
Which stage could become a bottleneck?
-
How much buffer does the line need?
-
How machines should respond to a shutdown
-
Which formats will be processed?
-
What product changes will be necessary?
-
how the equipment will be distributed within the plant.
MarCoPack’s design department designs each production line with the characteristics of the facilities and the type of production in mind, with the goal of optimizing the customer’s resources.
Optimize production
The true goal of a production line is to ensure that the line does not have to wait, since a machine that is idle while waiting for the next one represents wasted capacity. The same is true for a machine that is overloaded because the machine ahead of it is producing too quickly.
That’s why eliminating bottlenecks isn’t simply a matter of purchasing equipment with higher speeds.
It involves ensuring that all phases of the process are scaled, connected, and coordinated so that they operate at the same production pace.
For the Production Manager, this means a more stable workflow, fewer micro-downtimes, and a facility that is easier to manage.
For management, this means making better use of installed capacity, reducing operating costs, and achieving a faster return on investment in automation.
Does your production line run at the pace of your machines or at the pace of your bottlenecks?
If there are recurring bottlenecks, machines waiting for others, frequent operator interventions, or a significant difference between the theoretical output and the actual output at the end of the shift, the problem may not lie with a specific machine.
It might be in the way they all work together.
MarCoPack designs complete, fully automatic filling, capping, and labeling lines tailored to the product, the packaging, the production needs, and the available space at each facility.
Analyzing the process as a whole makes it possible to identify where losses occur and to design a solution in which filling, capping, conveying, and labeling function as parts of the same production line.
Because eliminating a bottleneck isn’t about making a machine faster. It’s about making the entire line more efficient.
Tell us what you need to automate, and we’ll design the most suitable production line. Contact our technical team.
Jose Martínez
Technical Office Manager MARCOPACK
