Why Shrink Packaging Machines Leave Wrinkles or Burn Holes in Film
After twelve years supporting packaging lines that use shrink tunnels, a frequent problem is packages that exit with persistent wrinkles, dog-ears, or small holes even though the L-bar or side-seal station produces sound seals. The defects appear only after the tunnel and are driven by the balance of temperature, dwell time, and airflow rather than by the sealing step itself.