Shrink films can be used in a number of different areas. They can be used to shrink-wrap objects of all sizes, from small parcels to aircraft engines or helicopters and pallets. They can also be used in the building industry, for all building or renovation projects, when it is necessary to insulate an area (asbestos removal site, protection against dust, etc.). Finally, shrink films are used for the winter storage of boats, as they make it possible to wrap them hermetically, to protect them from the rigours of winter and prevent possible break-ins. As shrinkage is generated by heat, a heat gun, or heat tunnel, is required to shape the packaging.
The composition of shrink films
Shrink films are polymeric plastic films that are available in a wide variety of variations. Depending on the use, a more or less thick film is required. It can be transparent or opaque, treated to preserve the container from UV rays, with different resistance and shrinkage rates, complying with health regulations for the packaging of food products, etc. Shrink film are very popular because the material adapts to any sizes and materials to be packaged, they are inexpensive, very light and easy to shape.
The different types of shrink film formats
Depending on how the shrink film is used, you can choose a different presentation. For medium-sized products, a shrink tunnel can be used, through which the object is transported on a conveyor belt. It can also be a shrink oven. The product, packaged without a bag, is then heated and the film around it shrinks until it forms a more or less hard shell that holds it in place and protects it from shocks.
For larger scale projects, the shrink film can be presented in a roll which allows the object to be rolled up, before using a heat gun to seal the package. Depending on the case, you can also find ready-to-use bags: the product is slipped into the bag, the opening is sealed and the whole thing is then heated. We refer to pouches for small objects and covers for larger packages, for a pallet for example.
It is also possible to place an object between two flat films and seal the sides one after the other, before heating the whole package.
How to shrink the polymer film
Shrinkage is a crucial step for good containment. Outside the tunnel or the shrink oven, a heat shrinking gun can be used. It can be electric or gas heated. You should start by wrapping the object you want to package.
Then take your heat shrink gun, which should be chosen according to the work to be done. It can therefore be electric or gas powered. For short applications, a compact gun with a gas cartridge may be sufficient. If work has to be carried out on large surfaces (construction, aeronautics, marine, etc.), it is preferable to use a gun connected to a trolley that holds a larger propane gas cylinder.
You must then heat the film, which shrinks to fit the shape of the package perfectly. Be careful not to overheat and avoid piercing the film. You should also be careful with the product to be packaged, which itself can be particularly sensitive to heat.
As it gets colder, the shrink film hardens until it forms a fairly rigid shell. When the film is stabilised, it becomes durable and weatherproof, allowing you to store your goods.