Label breakage is one issue that often go unnoticed during downtimes analysis but the impact it brought to machine downtimes should not be neglected. Label breakage happens when the label rolls from the un-winder could not withstand the opposite force acted from the label re-winder motor, which could be resulted from many factors.
Labelling productivity is affected when labels get ripped-apart during labelling process as the operator has to pause the process to remove broken labels from the conveyor and reconnect the remaining labels to the re-winder. Test on label dispensing functions and label gap are required to carry out to ensure on the following label placement accuracy.
There are multiple factors involved that could possibly contribute to label breakage:
1. Label Placement On the Applicator
The applicator of the labelling machine is a steel plate with sharp edge that allows label to dispense from the label roll. The label liner is required to be placed in between the applicator to prevent the label liner from shifting up and down during labelling process to minimize the chances of label breakage.
2. Label Die-cut
The thickness for label liner pose impacts on the label especially die-cut paper label. When labels are die-cut, they are actually being push down on the liner. A small split on paper liner that is hard to see might occur when the liner is thin. If that paper liner is hooked up to an applicator, the pressure and tension in that applicator can rip off the liner.
3. Label perforation
Always ensure the label roll on the labelling machine does not consists of perforation. The purpose of perforation on label roll is to ease manual label tearing process and strongly not recommended to use on labelling machine due to the high tension on applicator to dispense label during labelling process.
4. Length of Label Tongue
Label tongue is where the amount of label overhangs at the dispensing edge of the applicator before the label fully dispensed. The length of the overhung label decides how accurate the label placement go and the possibility of label breakage. The best length to maintain is around 3mm from the applicator steel plate; too long might cause the label to tear apart as the label could stick on the product earlier than the time the label dispenser is set to dispense label, causing breakage to happen.
5. Speed of Conveyor & Applicator
Synchronization is important to keep label placement accurate. Same goes to label breakage prevention. When the conveyor is running much faster that the label applicator, the label might be forcefully tear apart before it gets fully dispensed. Adding an encoder device could help to stay away from this problem by synchronizing the speed of conveyor and label applicator dispenser.
Published : 31-Mar-2021