DEAIR: increases productivity by removing the air

The innovative DEAIR system allows rapid and homogeneous degassing of the ceramic mixture during the moulding stage.

One of the factors that limit the productivity of a ceramic tile pressing line is the need to remove, during the compaction stage, the air that is caught between the ceramic powder granules while filling the mould cavity.
Careless degassing leads to defects that, in the finished product, may substantially make it useless on a commercial scale (stripping, “box” effect).
Until now, this operation has been carried out by subdividing the pressing into two steps (pre-compaction and compaction), as a result being more time-consuming, with additional wear and greater running costs.
The traditional pressing method also creates air flows from the centre towards the edges of the punch, which are the only escape routes available.
At high production rates these flows cause:

1. movement of the ceramic powder that has not yet been compacted towards the outside of the pressing cavity, which in technical jargon is called the “migration effect”.
2. Irregular distribution of the ceramic material with negative effects on the homogeneity of the tile density.
3. Pollution of the powders in production with double loading
4. Extensive use of liners and punches.
5. Pre-compaction burrs falling back into the moulding cavity
6. Greater stress on the isostatic membrane of the marking die, and therefore its subsequent risk of breakage.

The DEAIR de-aeration module, composed of the punch and special lower punch, solves the above-mentioned problems, by uniformly distributing several escape routes for air in the internal areas of the moulding cavity.