Customer requirement
A machine with an average capacity of 22,000 pouches per day fills and seals tubular bags with mustard, ketchup or mayonnaise.
To remove the liquids from the refill bag, a spout is welded to the inside of the film web. As the spout is soft, only slight pressure may be applied during welding to avoid crushing or deformation. The system must also ensure homogeneous temperature distribution with high temperature accuracy.
When welding the top or bottom seam, the biggest challenge is to ensure a tight seam. If there is a leak, liquid seeps out of the bags and production stops to allow for the necessary cleaning processes. There is also a risk that customers will complain about leaking pouches, entailing additional costs and effort.
From a hygienic point of view, the edge of the separating seam should be closed so that no contamination can occur.
Another requirement is to comply with the EU regulation on the reduction of packaging material. By 2034, companies must reduce packaging (plastic) by 10% compared to 2018 levels. Starting in 2030, small individual packaging will also no longer be permitted.
ROPEX solution
Thanks to the two ROPEX impulse sealing processes, ROPEX was able to quickly offer a customized solution. A RESISTRON technology ring heating tool is used to join the plastic film to the spout. At the customer’s request, the RES-5009 is used as a temperature controller to ensure seamless integration into the customer’s existing PLC.
ROPEX configured a CIRUS tool with a very wide heating track of 20 mm and three different counter layers for cut & seal specifically to meet the requirements of the top and bottom seams.
Thanks to cut & seal, the customer benefits from the material savings, as the material is cut directly in the middle of the weld seam. This eliminates the unwelded material protrusion between the sealing tool and the separate cutting blade.
Thanks to the high flexibility of the system, the customer can create three different cut-off seam contours with one tool: A simple parting seam, a parting seam with suspension holes and a parting seam with a tear notch.
The UPT-6006 controls the temperature, as the customer uses a PLC with Profibus. It regulates the heating impulses and ensures consistent welding parameters, making the process reproducible.
Customer benefits:
✓ Consistent weld seam quality under all operating conditions, both for welding in the spout and when employing cut & seal welding for the top and bottom seam.
✓ Reliable system thanks to exact reproducibility of the process parameters.
✓ Flexibility in the shape of the cut-off seam contour: Simple cut-off seam, cut-off seam with suspension holes, or cut-off seam with tear notch.
✓ Compliance with the EU regulation on the reduction of plastic by 2035.
✓ Low radiant heat, which protects the packaged goods.
✓ Highly dynamic heating and cooling due to the low thermally active mass of the welding tool.
✓ Simple, problem-free cleaning of the tool thanks to the water-resistant Fluid-Secure coating.
✓ The measurement of purely electrical variables such as current and voltage enables the measured values to be recorded with virtually no inertia.