Frequently Asked Questions-Fully Automatic Heat Shrink Packaging Machine | Shrinking Machine | Heat Shrink Film Packaging Machine | Fully Automatic Sleeve Wrapping and Sealing Shrinking Machine | Shanghai Guhao Packaging Machinery Co., Ltd.

Swelling: Hot air remains trapped inside the shrink film.

Increase the number of vent holes to accelerate air leakage from the shrink film.
Reduce the conveyor belt speed of the packaging machine to allow more time for hot air to escape from the shrink film.
Raise the temperature of the packaging machine to facilitate air leakage from the shrink film.

Hazing: The surface of the shrink film becomes blurry, resembling a thin mist.

Reduce the temperature of the packaging machine, as excessively high temperatures cause hazing of the shrink film. Increase the conveyor belt speed of the packaging machine to shorten the exposure time of the shrink film to heat.

Weak Sealing Line: The sealing line of the shrink film is prone to damage or develops small holes.

Reduce the temperature of the sealing machine's heat sealing blade.
Incorrect sealing line height; it should be half the height of the packaged item.
Uneven pressure on the sealing frame; adjust the horizontal position of the sealing frame.
The heat sealing blade or sealing base may be dirty; clean the heat sealing blade or sealing base.
The insulation pad or insulation tape on the sealing base is damaged; replace the insulation pad or insulation tape.
Sealing time is too short, and sealing pressure disappears before the sealing line is fully bonded; increase the sealing time.

Fish Eye: Wrinkles resembling fish eyes appear on the surface of the shrink film.

The temperature of the shrink packaging machine is too low; increase the machine's temperature. The conveyor belt speed of the shrink packaging machine is too fast; reduce the conveyor belt speed. The air circulation force of the shrink packaging machine is too low; increase the air circulation force.

Crow's Feet: A series of wrinkles appear at the corners and edges of the shrink film.

Excessive vent holes on the shrink film cause air to leak too quickly, preventing complete shrinkage. Reduce the number of vent holes, lower the conveyor belt speed of the shrink packaging machine, increase the machine's temperature, and raise the air circulation force.

Dog Ears: The shrink film forms protruding triangular shapes at the corners of the packaged item.

The shrink bag wrapping the product is too large; reduce the shrink bag size slightly. The conveyor belt speed of the shrink packaging machine is too fast; lower the conveyor belt speed. The air circulation force of the shrink packaging machine is too low; increase the air circulation force. The temperature of the shrink packaging machine is too low; raise the machine's temperature.

Incorrect Sealing/Cutting Position: The sealing line should be positioned at half the height of the packaged item.

Incorrect conveyor belt height on the sealing machine; adjust the conveyor belt height to the appropriate position. Incorrect sealing frame height; adjust the sealing frame height to the appropriate position. Incorrect air circulation direction of the shrink packaging machine; readjust the circulation airflow direction. The shrink bag wrapping the product is too large; reduce the shrink bag size slightly.

Crushed Packaging: The packaged item is deformed or crushed by pressure from the shrink film.

The temperature of the shrink packaging machine is too high; reduce the temperature. The conveyor belt speed of the shrink packaging machine is too slow; increase the conveyor belt speed. The shrink bag wrapping the product is too small; enlarge the shrink bag size slightly. The shrink tension of the film used is too high and unsuitable for the product; use a shrink film with lower shrink tension.