Burckhardt of Switzerland
Manufacture of POM rings for cold needle perforation
The main advantage of using POM polymer instead of metal is a huge reduction of weight. While a normal perforating ring of metal (aluminium core and brass outer ring) with a width of 100mm and an inner diameter of 80mm weighs 1700g, the weight of the POM ring with the same dimensions ranges at 400g.
Enormous weight difference
This weight difference of more than 1kg per perforating ring offers the following advantages:- The lower weight results in lower transportation costs and a smaller ecological footprint.
- When using an idle/non-motorised roller, the lower weight and thus lower mass of the perforating roller eases start and stop of the perforating process. This has a positive effect on perforating results. Holes will have a round shape rather than an oval shape.
- A shaft equipped with 16 POM rings has less deflection as it weighs approx. 20kg less. The effect will be a more homogeneous perforation pattern (hole diameter) on the total film width (left-middle-right).
- Last but not least, the purchase price of a POM perforating ring will be approx. 5% lower than a metal ring.
