The stretching value (pre-stretch) calculator makes it possible to check the settings of the machine, the stretching of the film and even to check the maximum values of both the machine and the film.
All you will need is a pallet to be wrapped, the film and the machine.

When entering the data use the thickness value formerly calculated by our system.

Specify the width and thickness of the film, enter the perimeter of the pallet and count the number of turnings taken by the pallet during turning. Besides, add the set pre-stretch value (optional).
After finishing the cycle, cut the film, crumple it up (squeeze out the air of it) and measure it on a scale with 1 g accuracy. From the above specified data, the system will calculate the extent of stretching and if you specified the machine settings before, the system will also show you the difference between the set value and the measured value.
IMPORTANT! Do not change the film density field, only if you know the value! Most stretch films available on the market are made of a raw material having a density of 0.92 g/cm3 . The chance to change this number is only given as some manufacturers use special mixtures for their unique film products. So if you know that the value is different, you can enter it into the system.

Tip: in order to check the maximum stretching value of the film or the machine, increase the pre-stretch up until the machine limit or until the point where the film is torn between the bloom-rolls. It is important that the film has to be torn between the bloom-rolls and not outside the film cart or on the corner of the pallet as these types of tearing originate from another property.
If you measure the film at this point, you will get a percentage value where the film was torn. Also you will get the value where the film achieved the maximum stretching value, so the maximum of the machine will be specified.
Film deficiencies mainly come from the fact that the maximum value of the film cannot be reached before the film is torn or we are in the belief according to machine settings that we achieved 200% of film-stretching, although the real value is much smaller.

If you place your mouse above the info buttons next to the input fields, you can check how to fill in the fields correctly

Start the calculation process