A few years ago as the price of oil steadily increased and finally reached $151+ per barrel (Jun 2008), new technologies quickly developed to minimize petroleum consumption in the manufacturing process of films and resins. These new discoveries led to using less oil while increasing the strength of these films (similar to the purpose of automation – doing more with less). In addition to films such as polyethylene (PE) now the market had polyolefin along with buzz words such as down- gauging or right-sizing in terms of maximizing the type of film to seal the product while minimizing the film’s cost.
To properly minimize the cost of film while maximizing its strength to seal and protect your product, it requires a good shrink system.
Shrink systems are available in two varieties:
- Semi-automatic – operator places the product inside the film and then slides it across the loading table and into the sealing area. Once inside, the operator pulls down the sealing bar (usually it has either a ‘hot’ knife or wire) melts or seals film around the product. After being sealed either the operator or the ‘takeaway’ conveyor will drive the product into the tunnel. Inside the tunnel, the hot air will shrink the film around the product to protect it to its next destination. Another semi-automatic solution called hood packers or nickname the ‘barbeque’ uses the same operator orientated loading process but when the product is inside the sealing area the plastic is sealed and heat is applied shrinking the film.
- Fully-automatic – the operator will load the product onto a powered infeed conveyor. The product will then enter into the sealing area where the product is encapsulated inside the film. Once inside, photo eyes tell the machine to lower the sealing bar, seal the film around the product using a hot knife or wire. After sealing, the product will be transferred by a powered conveyor into the shrink tunnel. Finally, the tunnel conveyor will discharge the product out of the machine.
To determine which shrink system works best for your application, we need to know:
- What is the product being shrinked?
- Its outside dimensions?
- Which film preference? Polyethylene or polyolefin?
- Is there a required film thickness (which gauge is required or preferred)?
- How many cases per minute?
- Does your facility have the necessary electricity to run this film?
Using these questions we can quickly determine which type of machine and film will satisfy your application.
Hood Packer System- Seals and shrinks all in one
Semi- Automatic Combo System- Operator loads product into film, lowers sealing bar. After sealed takeaway conveyor drives product into the tunnel for shrink film.
Fully- Automatic seal and shrink system- the product is conveyed into the seal area shown. Product is sealed inside the film then transferred by conveyor into a shrink tunnel.