A good knowledge of manufacturing techniques and sintering material process made Nuova IDROPRESS able to launch a new generation of batch pre-expanders. The new pre-expander has been realised, making it possible to improve the uniformity of the pre-foamed material density and reduce the cycle times. As a matter of fact, this is an improvement on the pre-foaming technique for original raw materials.

It’s a manufactured and patented new class of batch pre-expanders with an optimised structure capable of manipulating raw materials (in granules) according to a high-tech procedure , thus obtaining a better uniformity dimension and therefore a better density of the foamed level.
The pre-foaming uniformity is mainly due to the original lower, conic section shape which - unlike the traditional cylindrical chambers - makes it possible to obtain a meaningful raw material layer before the pre-expansion. This also enables steam injection without preferential ways (which can expand or even cause a collapse of the beads touching the preferential outlet without control).

The upper cylinder part collects the partially pre-foamed material and uniformly completes the process.
The advantages are a higher material uniformity and faster cycle times due to the fast expansion phase.

The new series includes pre-expanders ranging from 500 to 3500 kG/h ( 15 kG/m') able to satisfy any production of the manufacturing plant.