Sealing is the process of melting two layers of material together in a way that the two layers can not be separated without damaging the material.
This technique is used to close the opening of a bag. When a single reel of film is used, it can be folded to make the sides or bottom of a package. In the Audion Elektro machine range this method is frequently used. Most machines have 'sealing' as their only option. These machines are used when closing a bag or package is the only packaging goal of the user. Other machines are equipped with different options besides sealing for example: vacuuming to extend the freshness of the product, to protect the product or to reduce the volume of the package.
What should you consider when sealing? Not all materials can be sealed. A good seal depends on the melting point of certain materials. Polyethylene (PE) and Polypropylene (PP) up to 200 micron thick are perfectly suitable for sealing. The sealing suitability of laminates (multi layer material) depends on the inner or contact layer. Aluminum laminates and paper laminates can be sealed when the inside layer is polyethylene or similar heat sealable coating. Ensure you purchase the correct sealing machine for your packaging material.
Sealing options There are many options of seal width. Most standard Audion Elektro machines are fitted with a 3 mm sealing wire. This means that the seal on your package will not be wider than 3 mm. Some machines can be fitted with a wider, 5 of 8 mm, seal on request. Should you wish an even wider seal, you may consider choosing a 10 or 15 mm profiled sealing bar.
Extra security can be achieved when packing powders or liquids by placing two separate seals across the top of the pouch.
The bi-active sealing method, in which both jaws are with sealing wires, can be specified for sealing extra thick materials. The material will then be sealed from both sides.
A code seal impresses letters and numbers such as your company name or a packaging code into the seal area. This is produced by embossing the silicon buffer on the seal bar. When there is a requirement to print varying information on the package then several types of printing machines can be specified. This option however is only available on the more advanced machines.
Most standard machines are equipped with a cutting device. This device enables the user to cut the bag one centimetre above the seal to remove excess material or to make the bottom of a new bag when a roll of tubular film is used. Another option is to equip the machine with a seal/cutting wire. This is a wire that seals the bag and cuts it exactly on the seal in a single operation.
