Impulse Heat Seal Knife Cut/Seal and Cut Capability
Incorporating a cutting feature into heat sealing equipment can be a value added process to trim excess film material. There are two different methods of cutting films.
The first is a Knife Cutting System. Knife cutting involves a moving blade while the film is stationary within the heat sealer. A knife cutting approach leaves some un-sealed space between the heat seal and where the knife travels.
If an unsealed portion of film is undesirable, another method called Seal and Cut is possible. Seal and cut refers to a special heat seal band with features allowing to melt through films and seal exactly to the end of the film where it is trimmed. Seal and cut heat seal bands can take many different forms.
Trial and analysis is required to understand what works best for specific film materials and their thickness. Packworld recommends sending sample film in for testing to identify the best options. Not all films are able to be cut cleanly.
The Seal and Cut operation does introduce more stress to consumable materials such as PTFE tapes and heat seal bands. More frequent replacement of consumables is usually associated with Seal and Cut applications when comparing them to a seal only application.