What is the pre-stretch film?
The pre-stretch is stretch foil, which is stretched in advance almost to the breaking point and then rolled on to a roll for final use. This means that the foil does not require as much stretching energy as the usual stretch foil to reach the same stretch. For this reason, pre-stretching is becoming increasingly popular for manual packaging. Through it, manual packaging can achieve the same stability as machine packaging.
The pre-stretch foil is produced by stretching a roller between two rollers of different rotational speeds. The final roll has the greater speed of rotation than the main one, which leads to the stretching of the foil to the required extent.
As a result of the pre-stretching, the rollers are light and easy to use, and even with a manual roll we can get as close as possible to the packing quality of the palletizing machine. This reduces fatigue in the employees who use them. The effort for stretching and twisting is small and allows the worker to move forward, which reduces possible slipping and falls.
Real-world studies in different companies show that the average stretchability an employee achieves when using standard stretch film is less than 15%.
Due to the fact that the pre-stretch is much thinner than the standard stretch, the worker uses less material for the packaging of the same amount of goods, which also leads to significant savings.
Main advantages of the pre-streaker
1) Price
Pre-stretch consumption can be up to 50% lower than the standard stretch. This leads to economic savings of 25-40%.
2) No losses from damaged ends of the rollers
It is almost impossible to damage the roll with a stretch when it is dropped.
3) Easier to use
The required stretching effort is much less, allowing the operator to go forward rather than backward. This leads to greater safety and more control. Also, less physical strength is necessary for stretching and packing. The roll is about 2/3 lighter than the standard stretch roll of the same length and easier to use. The thickness is half and the force of which it lasts – double.
4) Foil memory
Since the film is pre-stretched and applied to the production with little force, it does not deform the packaged goods (e.g. cartons), while keeping them sufficiently reliable. This is perhaps the most important reason for the use of pre-stretch film.
5) Perseverance of tightening power
The tightening power of the standard stretch is unpredictable, since it is difficult for the worker to achieve equal stretchability everywhere. In case of fatigue, efforts decrease and remain areas of production or pallet that are not well packaged. This can lead to the breakdown of production during transport. The tightening force of the pre-eaves is much more controllable and even.
One of the main pros of the pre-streak, namely the small thickness, in some cases is also its minus. When we have sharp edges to pack, it’s easier to pierce the thinner pre-stretch. The solution in this case is the use of paper corners.