In the absence of strict wrap standards and regular testing, stretch wrapping can seem more like an art than a science. The items need to be stacked correctly and the pallet needs to be wrapped to contain the items, preventing damage while keeping the continuity of the pallet during shipping.
Still today, a very common, but least efficient and effective pallet wrapping method is hand wrapping. Generally 1 or 2 people with a wrapping gun simply walk around a stacked pallet, or rotate it on a carousel, and dispense the film over the packed goods.
It is a labor intensive activity with the chance of injury greater than with any type of machine wrapping, and, depending on volume, it could require more time, effort, and cost than using a machine wrapping method.
Additionally, hand wrapping is one of the worst ways for ensuring adequate containment force. Containment force, the hugging pressure of the stretch film that holds the load together, needs to be adequate everywhere on the load. When hand wrapping, it is difficult to wrap to a set containment force standard. Overall, hand wrapping is inconsistent and hard and tedious work.
Below is a list of the 4 most common pallet wrapping options explained to give an insight in how they work, what to expect and the specific reasons for using these methods.
Automatic vs Semi-Automatic Stretch Wrappers
To understand the common types of stretch wrappers, it is important to first discuss the difference between automatic and semi-automatic machines.
An automatic stretch wrapper takes a pallet from the beginning of the line, and automatically feeds it into the wrap zone where it is wrapped according the settings on the control system. When finished, the pallet is conveyed to the end of the line, while a new pallet is automatically being conveyed into the wrap zone.
A semi-automatic stretch wrapper, by contrast, requires an operator to load and unload the machine, start the wrap cycle, and make the appropriate adjustments to ensure the load is wrapped effectively.
1. Turntable Wrapping
In its simplest form, the pallet is placed on a turntable that rotates while a film delivery system dispenses the stretch film around the load. The film delivery system usually starts at the bottom of the load, wraps to its top, and then wraps back down to the bottom.
Turntable wrappers are the most prevalent type of stretch wrapper and can be configured to work effectively with a wide variety of applications.
2. Straddle Wrapper
Unlike turntable machines where the load itself is rotated, in straddle stretch wrappers the load remains stationary while film delivery system rotates around the load. These types of wrappers can handle unstable, light, and heavy load and can wrap from low to high volume.
3. Ringer or Orbital Wrapper
A ringer or orbital wrapper wraps a pallet over and under, typically as the load moves on a conveyor through the machine. They are generally used for, flattened, or unwieldy loads like doors, pipes, carpet rolls, coffins, etc.
4. Ring Straddle Wrapper
These are high speed wrappers that can handle up to 200 loads per hour. They're often found in the tissue, paper towel, and beverage industries. Ring Straddles are highly specialized machines and are only a small proportion the stretch wrappers in use today.
The Right Wrapper for your Needs
These are four basic, common stretch wrapping options. Each of these types of stretch wrappers has optional features and add-ons that expand their capabilities and flexibility. If you are unsure where to begin the process of choosing a stretch wrapper our Automatic and Semi-Automatic buying guides are great places to start.
You may be interested in these related posts:
- Damaged Products Hurt Your Company's Bottom Line
- Should I Buy a Used Stretch Wrap Machine?
- Pallet Wrappers: Making Shipping Better, Simpler, Cheaper And Faster