In vertical form fill seal (VFFS) machines, heat sealing and ultrasonic sealing are two common methods used to close packages, each suited to specific materials and applications. Heat sealing relies on controlled heat and pressure to bond film layers and is widely used for both standard and multi-layer laminated films. It offers consistent results and remains the most common sealing method in automated packaging.
On the other hand, ultrasonic sealing uses high-frequency vibration rather than heat to join the film layers. This method is particularly useful for temperature-sensitive, recyclable, or specialty films, as it minimizes heat exposure while maintaining strong and reliable seals.
If you’re exploring which sealing technology best fits your packaging line, Unified Flex can help you evaluate material compatibility and select the right VFFS solution for your application.