Commercial Labeling System Maintenance and Repair
There’s no way to completely eliminate downtime and repair costs for your labeling equipment, but there are ways to reduce them. What are the most common problems you’ll encounter with your labeling machine, and how do you fix them before calling your repair service provider? Learn more about how to manage your commercial labeling system maintenance and repair.
How Does a Label Applicator Work?
Labels are loaded on reels and run through the machine. The liner’s path is called the “web.” From there, processes differ depending on the type of label printer. If you have a print-and-apply system, the web passes through the print engine before heading off to the applicator. Direct thermal printers heat thermal paper with the print head, while thermal transfer printers melt ink from a ribbon onto the label. Some labelers have a hopper to store printed labels until they are applied to packaging. This adds a buffer to compensate for product loading fluctuations.
Sensors detect the position of the label and the position of the container or carton. Most machines use light sensors, but clear labels require resistive sensors. Sensors detect the thickness of materials and tell the difference between bare liner and liner covered by a label. The labeling head uses a stepper motor to feed in the next label for application. A peel tip separates the label from the liner. Meanwhile, containers are loaded onto the machine. Our semi-automatic labelers have a hopper that holds containers until they’re picked up by the star wheel for labeling. Our automatic labelers have conveyor belts that pick up products as they come off the manufacturing line.
There are several ways to apply labels to containers. Wipe-on applicators press the label on with a brush or roller. Tamp/blow applicators dispense a label onto a pad held by vacuum pressure which then presents the label close to the product and uses a quick blast of air to blow the label onto the product.
Label formats can be sent from your warehouse management system directly to the print engine. This allows operators to customize labels to be printed on demand, utilizing an array of text and barcodes.
Feed Errors
Most feed errors are caused by label sensors that aren’t set up correctly. It’s easy to turn them off by accident or forget to change the calibration when switching labels. Fortunately, an easy troubleshooting method to fix this problem is by checking the PLC (the labeler’s data management system). Our systems can store several label configurations, so you can switch to the right one without having to recalibrate the system.
You should also check how long it takes to get a feed error. Let’s say you’re using 6-inch labels. If the PLC is set to look for a label edge after two inches of liner have passed, it will always give an error. If you set it to 18 inches, there will be plenty of time to detect the next label, while only wasting one or two labels when there’s a problem.
Roller Problems
Sometimes, labels will stick to rollers or adhesive build-up on surfaces. Your commercial label system preventive maintenance routine should include wiping down rollers with an appropriate cleaner to remove buildup. Never use a blade to remove adhesive and labels, as there’s a risk of nicking the roller.
If the labels aren’t transferring correctly, make sure the roller isn’t loose, and any connected pulleys and belts are in good working order. Any slipping in the system can stop the movement of labels.
Print Engine Problems
While print engines are built for constant use in extreme conditions, they’re also a leading cause of commercial label system repairs. Print and apply systems also add to the list of commercial label system maintenance tasks, including cleaning, head replacement, and ribbon replacement.
A dirty head has trouble activating paper or melting ink, resulting in missing lines or smudged prints. This buildup also absorbs heat, forcing the head to run at higher temperatures to compensate. This shortens the head’s life and reduces print quality. Cleaning pens and isopropyl alcohol can be used directly on the head, while canned compressed air is useful for blowing out dust inside the engine. Never use air from an air compressor. It contains moisture and oil that will damage the print head. Abrasion from rough label stock wears out heads faster. Consider a smoother label finish for direct printing, and make sure your ribbon is wider than the label if you’re using thermal transfer printing. If you want to learn more, check out Sato’s article on thermal print head life. These tips apply to all print engines.
The Liner Tears During Label Application
The peel tip should be part of your commercial label system maintenance routine. If the tip is worn out due to high-volume application, the edge will catch on the liner as it passes through the applicator. Friction on the tip is also an issue. This can usually be fixed by applying ultra-high molecular weight (UHMW) tape to the tip. This tape has a slippery surface that helps the tip glide between the liner and the label. Sometimes, the problem comes from small tears on the edge of the liner. These tears are formed at the label factory when the liner stock isn’t cut correctly.
The Label Follows the Peel Tip Instead of Rolling Onto the Container or Tamp
The tension on your applicator might be too low, keeping the tip from transferring the label. Webbing issues also cause this problem by altering the angle or tension of the liner as it enters the machine. Too little or too much adhesive on your labels can interfere with peeling. If the glue is too thick, the label won’t peel properly. If there are voids in the adhesive layer, the label will catch on the applicator once it hits the next section of glue.
Label Skewing: A Common Design Issue
Misalignment of the web or the applicator can cause occasional skewing, but consistent issues are usually caused by the label design. Even containers that look flat often have a slight angle to them. For example, plastic containers use a 15-degree angle on surfaces to help them release from the mold on the production line. While this isn’t noticeable when you handle the container, it’s enough to cause a flat label to twist during application. Skewed labels are not the face you want to present to consumers.
Protecting the Labeling Machine From Dust
The frequency of commercial label system repair has a lot to do with where your equipment operates. While a temperature-controlled, dust-free environment is ideal for your labeling equipment, that’s not easy to achieve on the production floor. However, there are a few things you can do to reduce wear and tear from dirt buildup.
- Blowing compressed air around the labeler keeps dust and other contaminants from landing on the applicator surface and the surrounding rollers.
- Condensation isn’t just a problem for label adhesion; it also collects dirt. Use an air knife to blow away moisture before it can drip onto the machine.
- If dust is a problem throughout your facility, it may be worth investing in a vacuum, air cleaning, or fogging system to settle the dust out of the air.
We Can Help Keep Your Equipment Running
Every commercial label system repair adds to downtime. If you want to save money on equipment repairs or need to upgrade your label printing capability, contact CTM Labeling Systems. We have local distributors that will help you evaluate your labeling process, so you can find a high-quality labeling solution that’s effective, reliable, and cost-effective.
