What are carton sealers? Carton sealers automatically place adhesive tape to the top & bottom of the box simultaneously. The operator simply folds flaps of the corrugated carton and feeds it into the machine. Our carton sealers are reliable, cost-effective and durable providing savings to your production process.Heat sealing, or thermal-bonding, is the most common form of sealing in the packaging industry because of the excellent results it provides. It consists of using heat to weld one thermoplastic to another thermoplastic, or another material, at a certain temperature and pressure.The carton sealing machine, also a cardboard box sealer, is a device used to fold and seal the cardboard carton efficiently. A standard carton sealing system includes the sealing equipment and a worktable.