Stretch wrappers most commonly use low-density polyethylene, which can stretch up to 500% of its length before breaking. The film is typically only stretched 100 to 300% when in use, and once it is stretched the elastic recovery keeps the load tight and secure. In warehouse and industrial settings, stretch wrappers most commonly serve the following functions:
- Improved stability of products and packages, which forms a unit load
- Easier handling and storage of unit loads
- Contents are protected from pilferage because product is harder to access once wrapped
- Contents are protected against dust and debris to some extent
The three common types of stretch wrappers are manual, semi-auto, and automatic. Each of these types come in a few different styles as well, so here is a brief summary of each.
Manual stretch wrappers come in three different styles. An extended core stretch wrapper is just a roll of film with an elongated spool, which acts as handles on either end of the film. This is the least consistent method of stretch wrapping because the tension is controlled by hand. There are also mechanical brakes, which provide resistance against the film to create stretch. The last style of manual stretch wrappers are pole wrappers, which are similar in style to the mechanical brake wrapper. Pole wrappers use an extended pole with the roll and brake at the end, eliminating the need to bend and reach.
Semi-automatic stretch wrappers also come in three different styles, turntable, orbital, and rotary arm. Turntable wrappers use a turntable that the load is positioned on, and spins while the film roll moves up and down on a fixed mast. The stretch is achieved because the load is rotated faster than the film is fed. Orbital wrappers use a vertical rotating ring to apply the stretch wrap to products moving horizontally through the ring. Products are either suspended in the ring by hand, machinery, or conveyor. Rotary arm stretch wrappers are the last style, and with this system the load stays still while the rotating arm turns around it, wrapping it with film.
Automatic wrappers are similar in design to semi-auto, but there are automated systems to load the machine, and apply to, seal, and cut the film. Automatic stretch wrappers come in turntable and rotary arm styles as well. The only style that is unique to an automatic wrapper is the rotary ring wrapper. This style houses the film on a horizontal ring which moves vertically relative to the load being wrapped while the load stays in place.
The more high volume shipments you have going out, the more likely your facility could benefit from an automatic or semi-automatic stretch wrapper. If your operation is small or you don’t frequently have full pallets to ship, a manual stretch wrapper might be more fitting. When making this decision, be forward thinking and try to forecast where your company will be in five years. A manual stretch wrapper might be enough for today, or the next two years, but a few years down the road you might have to replace it with a semi or fully automatic setup to meet your shipping needs anyway. You should always consider upgrading now and saving money in the long run, as this applies to many different types of material handling equipment.
This might be hard to determine on your own, but that is where ASI comes in to help. We will determine what you are handling and at what volumes, and help make the best decision based off of your unique situation. Our professional sales team will work together to get you the proper solution for your specific material handling problem.