If you have a pallet wrapping machine working on your production line, then you’ve already been sold on the benefits it can bring to your bottom line and productivity. What you want is for your investment to continue to work efficiently, without problems that lead to a slowdown in production or potentially expensive repairs. Here are some common issues that you may come across and how to solve them.
The problem: stretch wrap film breaking
Film breaks are a common concern in stretch wrapping. The first factor to investigate is the quality of the stretch film you are using. A cheap film is more likely to be prone to breakage because it may have flaws such as tears and nicks. Also, check-in with your operators to see if they have the necessary skills, and invest in training if you feel this will help. You need to ensure they are correctly feeding the film through the film delivery system. Put in place systems that ensure the film isn’t damaged through mishandling or dropped, causing nicks and weaknesses that lead to breaks. You can also limit your risk for film breaks by:
- Paying attention to your load profile.
- Prevent products from protruding from the load.
- Correct any sharp corners.
The problem: how to stack a load so it’s stable
If you are having challenges stacking a load, you need to look into how you can make the layers consistent. Remember the stability will differ when stacking a square load with flat cases, compared to a load with unstable products. A square, heavy load will likely rotate well on the turntable of your stretch wrapper. However, a tall, light load will be challenging. Consider reducing the load height or trying it on a machine that doesn’t require the load to rotate.
When it comes to stacking, place the heaviest products on the bottom of the pallet. This should help with weight distribution and prevent products from getting damaged. The load should also be kept equal to or within the perimeter of the pallet. If it’s smaller, you will not be able to lock the load to the pallet. If it sticks out, the product may get damaged.
The problem: shipping damage is costing me money
You’re not alone. Research shows that 0.5% of shipments of food, beverage, and consumer products are lost to damage. The damage occurs between the point of production and the point of sale. Stretch wrapping can reduce the damage that happens when your products ship to your customers by as much as 50 percent.
The problem: I’m experiencing wrap wastage
You may be using the incorrect sizes of stretch wrap for your applications and products. When you use the wrong size of stretch wrap to wrap your products, you not only waste wrap, you risk improper load containment. The size and shape of your products and the width and height of your pallets will determine the wrap you should be using. You may need the advice of a packaging expert who can analyse your current wrapping materials and machinery.
It’s also possible you are using the wrong size of stretch wrap. If it’s too thin, it may lead to consistent tearing. If it’s too thick, you will be wasting material.
The problem: I’m seeing marks and inconsistencies in my wrap
There are two possible reasons. You are either using the wrong kind of plastic wrap, or heat. Here are some of the shrinkwrapping issues that you could be experiencing and how to solve them:
Dog Ears. These are triangular protrusions of the film on the corners of a package. It is caused by insufficient shrinkage of the film, so the corners do not shrink down enough. Look into the heat – the areas to look at are the shrink gun/tunnel. Is it putting out sufficient heat to wrap the package correctly? Also, assess if the size of the shrink wrap is correct.
Crow’s Feet. These are wrinkles extending from the corners of packages. They are caused by excessive film on the corners of the product. Use a smaller shrink wrap.
Fish Eyes. These are round patterns in the plastic on a package and are caused by a lack of heat. Check the heating element and schedule maintenance if needed. When the heat source doesn’t push enough air when it applies heat, the wrap won’t shrink consistently. If there are perforations in the wrap, you may experience this issue too. To fix, slow down your conveyor speed.
Angel Hair. These looks like thin strands. They stretch from the product and the sealed part of the film. They are likely caused by sealing wire or a seal bar not being hot enough, or alternatively the conveyor speed.
Ballooning. This happens when the film is exposed to hot air after sealing. To prevent this, switch to using pre-perforated film. The small holes allow air to escape as the film shrinks around the product.