3. Calibration of tubes and profiles without vacuum

This allows vacuum-free calibration of tubes made from various types of material. The new calibration system takes into account the characteristics and behaviour of the material during cooling and supports its spontaneous behaviour.

For pipes up to 10/15 cm in diameter, no calibrator is needed. For pipes with a diameter larger than 10/15cm, a special calibrator made according to the size of the pipe and the type of material is used. Calibration always takes place at atmospheric pressure. This allows higher extrusion speeds, especially for pipes with a diameter up to 10/15 cm.

As there is no longer a vacuum pump, the noise and energy consumption associated with the pump is totally eliminated.

The absence of the calibrator or the special shape of the new type of calibrator allows to make diameter corrections during calibration and to increase the speed of the pipe suring extrusion.

The new calibration system avoids the cyclic dimensional changes and is, therefore, able to provide reduced dimensional tolerances. This type of calibration works optimally in combination with the adaptive temperature control system and energy saving in extrusion.