Advantages of BSA rolls

BSA rolls were specially developed for a high-quality production of sheets
and thin foils. These deflection resistant highly-precise rolls render feasible the production of thin foils in the range of
150 µm to 800 µm by smoothing technique only. By avoiding air knives an optimum surface quality can thus be achieved. Thickness tolerance is 1% of foil thickness only, i.e. 10 times better than with the use of conventional rolls.

The principle:

Ideal
In case of an idealized straight roll geometry a sheet with parallel surfaces and therefore uniform thickness is produced.

Real
Molecular forces within the sheet cause a linear load onto the rolls which will suffer a deformation as a result of bending and bulging.

BSA-Compromise
By means of a patented design the linear load is absorbed by an inner axis, which transfers the torque onto the outer shell at the same time. In that way the deformation of the outer shell is reduced to a minimum.

The advantages:

Saving of raw material
Approx. 6% of the raw material needed when using conventional rolls can be economized as a result of the diminution of thickness tolerances by factor 10. With an extruder capacity of 500 kg/h and a production time of 24 hours on 200 days a year one achieves a yearly saving of:

500 kg/h x 24 h x 200 days x 6% = 144.000 kg/year

Variable nip adjustment
Since crowns, bending or crossing-over of the rolls can be renounced by using BSA rolls, any sheet thickness can be produced with one single pair of rolls.

Best thickness tolerances and best surface qualities