Producing PU gaskets in just seconds

Automated FIPFG system offers maximum flexibility in series production

Foam gaskets made of polyurethane (PU) protect components from dirt, dust and moisture. They are used both in classic automotive construction and in the field of mobile energy, for example in electric vehicles, e-scooters or charging stations. PU foam gaskets are applied, for example, to components for loudspeakers, lights, ventilation grilles or tank caps using the FIPFG process (formed-in-place foam gasket). A fully automated system that meets all requirements in terms of process reliability and quality standards is suitable for series production with high quantities.

With the dynamicLine, DOPAG offers such a system. At the same time, it ensures the user maximum flexibility in series production, as several different components can be provided with a PU foam gaskets at several points. The core of the system is the dynamic mixing head. It processes the highly reactive, multi-component polyurethane. Robots are integrated into the system concept for handling the components. Various systems, such as for pre-treatment and for process monitoring, can be easily added.

The dynamic mixing head is suitable for processing highly reactive materials. In addition to sealing foams, these also include adhesives and potting compounds. Thanks to a programmed controlled overlap, the start and end points of the foam bead merge into each other, resulting in an optimal coupling point. In addition, a Nozzle Closing System (NCS) ensures a seamless closure of the foam gasket. It prevents drops from forming at the cannula outlet, which could then lead to an unclean sealing bead or contamination of the component or the belt system. The material is supplied via two pressure vessels. Refill units ensure a constant material flow and uninterrupted production. This ensures clean, process-reliable and high-quality production of the PU foam gaskets in series production at all times. 

The dynamic mixing head is suitable for processing highly reactive materials. In addition to gasketing, it can also handle adhesives and potting compounds. Thanks to the programmed controlled overlap, the start and end point of the foam bead merge into one another, producing an optimal coupling point. The nozzle-closing system (NCS) is an additional feature that ensures seamless closure of the sealing bead. It prevents dripping at the nozzle opening, which could otherwise create an untidy sealing bead or make the component or belt system dirty.

Once the material is applied, the robots place the components on a specially designed conveyor belt, where the PU gasket hardens at room temperature. The conveyor belt has been designed and synchronised to cover the entire time needed by the gasket to harden, so that by the time a component reaches the end of the belt, the gasket has fully hardened and the component can be removed and further processed.

High process reliability in series production
Extensive process reliability systems were installed to meet all of the requirements of the automotive industry and ensure consistently high quality. Right from the start, as soon as a component is manually placed in the system, camera sensors verify the component type against the programmed preset. Components that do not match the preset type or cannot be identified are rejected. Each time the system is restarted, the grippers and the nozzle of the mixing head are checked for damage. If no damage is detected, the system starts in regular production mode and the material is metered, mixed and applied.

Material supply
The material is supplied via two material pressure tanks for the A and B components, in which additional functions are integrated, such as a controlled air supply to the A component or fine filtering of the B component. High-precision DOPAG gear pumps meter the material, aided by a refilling station that ensures continuous, automatic filling and uninterrupted production. A temperature control unit is also installed. The temperatures of the material pressure tanks, hose lines and mixing chambers are controlled using a heat transfer medium, so that the material is always at the right processing temperature. With this feature, the system covers all considerations, ensuring the clean, reliable and high-quality completion of PU gaskets in series production.

More information about the companies can be found here:

GEALAN Formteile GmbH
Hofer Strasse 70 - 74
95145 Oberkotzau
Tel.: +49 (0)92 869 460

Foster Electric 

FIPFG: Series production of PU foam gaskets