How to Measure Your Containment Force
We’re going to help you understand how to measure your containment force, so you can make sure your pallets and unitized loads are prepared for transport. Measuring your stretch wrap containment force is actually quite simple. You multiply the number of revolutions applied by the wrap force (or tightness) of your stretch film.
Containment Force = # of Revolutions x Wrap Force
When you go to measure the containment force of a stretch-wrapped pallet, you need to check three critical areas: the top, middle, and bottom. Containment force varies at each of these locations, so you need to make sure you have the correct amount of force in all three places. The recommended level of containment force changes based on the size of the load. Below are some general suggestions for different load weights. You can always speak with a packaging professional to get a recommendation based on your specific packaging strategies.
To give you an example, let’s say you have a medium-sized load that weights about 1045 pounds. You’ll want to measure a containment force that is at least 6 to 8 pounds in all three locations. Because 1045 pounds is a heavier load in that category, we’ll probably want to get around 8 pounds of containment force. When you take the measurements, you find inconsistencies from top to bottom.
Top: 7.4 pounds
Middle: 5.6 pounds
Bottom: 7.9 pounds
These measurements suggest that the middle of the pallet is not stabilized properly. We certainly don’t want items to start jetting out in the center of the load. This could easily cause the stretch film to tear and compromise the entire unit.
While the top and bottom of the pallet are within the recommended levels, this medium load is quite heavy at 1045 pounds. We’ll certainly want to increase the containment force in the middle but increasing the top and bottom is also a good idea based on the weight of the load.
Let’s look at some of the ways we can increase the containment force on this load and better stabilize the unitized items.
How to Fix Your Containment Force
To fix the containment force of a load, there are two simple methods. The first is to increase the wrap force or the tightness of the stretch film. This will apply a larger containment force on the load, but it could cause some additional problems if you’re not careful. You can wrap a pallet or unitized load too tightly, which will crush boxes or containers and possibly damage your products. A high wrap force also makes it easier for the film to break as it’s being applied.
The second option for fixing containment force is to apply more revolutions. Adding more revolutions around the pallet will increase the level of containment force applied. However, you’ll want to consider the effect that this method has on your material costs. Adding more revolutions means adding more stretch film, which could cost you more than you think in the long run. We suggest working with your wrap force as much as you can before you start adding more revolutions.
With our earlier example, let’s simply adjust the wrap force to make the stretch film tighter because we’re fairly confident that it won’t crush the boxes. We’ll increase the wrap force to increase the containment force.
Now we get these measurements:
Those levels of containment force look much better from top to bottom. Now, your load is ready to be shipped to its destination.
When to Measure Your Containment Force
The containment force is the most important factor for determining if a load is ready to travel. For most companies, you’ll figure out what works for your load and set the measurements automatically. You won’t have to worry about the applied containment force every single day, but you should still check it periodically make sure things stay consistent over time.
You’ll always want to measure your containment force again after your packaging system changes. This could mean you’ve changed stretch wrap gauges, organized a load differently, or messed with the settings on your stretch wrap machine. Anytime you change the way things are done, you need to check your containment force again.
Hopefully, you can confidently measure your containment force and know that your load stability is just right. This crucial step of the packaging process ensures every load arrives in pristine condition, and therefore, your products remain perfect until they reach the customer.