Cutting sheets by sawing produces chips as a by-product which sticks on the surface and lead to surface defects when the sheets are stacked. A new chipless cutting technology developed by EMO-Extrusion Molding GmbH from Upper Austria for sheets with thicknesses of up to 12 mm produces a perfect cut quality, clean sheet surfaces and a high overall quality.
Good surfaces determine high-class plastic-form parts, e.g. sanitary components, made from extruded sheets. But as extrusion is a continuous process the extruded band sheet subsequently has to be cut into individually sized single sheets. The cutting can be effected in different ways, by the classical saw, the guillotine cut or the knife cut. With sawing chips and dust have to be removed by means of a suction system and/or an additional cleaning process. The guillotine cut is limited to a small range sheet thicknesses, the knife cut is not applicable universally for all plastic types and sheet thicknesses and produces also chips.
All the conventional cutting methods and devices require post-processing. As a result the Upper Austrian enterprise EMO Extrusion Molding GmbH, a member of the Haidlmair group, started to look for alternatives. After 2 years of development and testing a new sheet cutting device is ready for the market. It avoids all present disadvantages and is applicable universally for all extruded plastic sheets to 12 mm thickness.
Instead of a circular saw it uses specially designed cutting tools arranged to sets of two or three cutters in a joint fixture. Each tool combination is individually adjusted to a specific sheet thickness and can be exchanged quickly with single screw clamping. The cutting process is a combination of shearing and displacing and produces no chips or dust as by-products. The cutting edge is clean, steady and free of burrs. Costly cleaning before palletizing the sheets is not necessary, resulting in lower overall process costs.
Tuned to the most common sheet formats the EMO sheet cutting devices are available in three sizes designed for a cutting width of 1400, 1900 and 2,300 mms and a maximum sheet length of 2,300 mm. In standard execution the maximum cutting capacity of 12 mm sheet thickness is independent from the type of plastic material. Upon special request alternative versions for higher thickness can be offered.
The cutting unit is servo-driven and synchronized with the feed speed of the extruding line in the speed range up to 10 m / min. The cutting stroke is servo-driven as well and can drive the cutting tool up to a speed of 50 m / min. As the EMO cutting system works without a driven circular saw, thus without motor, there are no vibrations affecting the cutting quality and no additional sound emission. Consequently no additional noise protection housing is required. In addition, an investment in a suction system is not required. Overall the new EMO cutting system provides an excellent price / performance ratio.
The EMO cutting devices are designed as downstream units for integrated sheet extrusion lines. In addition to the new cutting devices a comprehensive scope of additional units are available, e.g. stacking devices, with or without robotic palletizers, as well as with or without palette transfers.
The EMO Extrusion Molding GmbH founded in 1996 is engaged in extrusion dies development and production, specializing in flat dies for film and sheets. The range of products comprises mono and multi-layer-nozzles (up to 7 layers), co-extrusion adapters for PO and PVC, as well as periphery for extrusion lines like sieve band filter, traverse cutting devices, calibrations for XPS sheets up to complete lines for PVC structural foam sheets.