Wrinkles on finished granule packages are typically caused by issues in packaging film quality, heat-sealing temperature, mechanical adjustment, product filling volume, and component wear. Identifying the specific cause requires checking each of these areas systematically.
1. Packaging Film Problems
Film quality has a direct influence on the final package appearance. If the film has uneven thickness, surface defects, or has absorbed moisture due to improper storage, it cannot stretch evenly under tension during the packaging process. This uneven deformation frequently results in wrinkles on the bag surface.
2. Incorrect Temperature Settings
Heat-sealing temperature is a critical parameter. When the temperature is too high, the film becomes overheated and softens excessively, causing it to deform and wrinkle during pressing. If the temperature is too low, the film layers may not fuse completely, and subsequent tension during conveying can produce wrinkles. For consistent sealing, the temperature should be matched to the film type and thickness.
3. Mechanical Adjustment Issues
The coordination of machine components is essential. For example, uneven pressure from the pull rollers can cause the film to drift and wrinkle. Similarly, incorrect tension settings on the film feeding system or the forming collar can make the film too loose or too tight during transport, leading to wrinkles. When standard forming collars, pull rollers, or tensioning parts cannot achieve uniform film movement for special bag sizes, Hansheng Automation can machine custom components based on customer drawings to improve tracking and tension control.
4. Filling Volume Problems
The amount of granular product filled into each bag also affects package appearance. If the fill volume is too high or too low, the product distribution inside the bag becomes uneven. When the granules concentrate on one side, the opposite side of the film lacks support and may collapse, forming wrinkles. Adjusting the filling device and checking the drop timing can help distribute the product more evenly.
5. Machine Wear
After long-term operation, key components gradually wear. If heat-sealing jaws or cutting blades become worn or uneven, they cannot produce a clean seal or cut. Instead, they may pull or squeeze the film, which is a common cause of wrinkles. Replacing worn sealing jaws and cutters and verifying their flatness can restore package quality.
In summary, wrinkles on granule packages from a high-speed rotary packaging machine usually result from a combination of film condition, temperature, mechanical settings, fill level, and part wear. Checking and adjusting these factors in order is the most effective way to resolve the problem.
