Flexible ring for thickness control

The Flex Ring system was developed by ST Soffiaggio Tecnica for the dynamic control of radial thickness. This new system is based on the controlled distortion of the die, which is made of a special kind of steel and is directly integrated on the extruder head. The system can be fitted not only on new machines, but also, where mechanically feasible, on existing ones. The die distortion is monitored by a system with 500 variation points controlled by electric motors or by servo-valves, for small or large diameters respectively.
In addition to adjusting and levelling the thickness of the extruded parison, Flex Ring enables a considerable reduction in the part's weight, thus offering a range of benefits in terms of production cycles and savings on raw material costs. In the manufacturing of 1000 litre IBC containers, for example, the part's weight was reduced from 17 kg to 15 kg by increasing the thickness in critical points and decreasing it in less important areas.