Mold Filling

A special form of casting is the injection of the casting compound into a mould consisting of two halves, which is mounted in a clamping machine. This molding process is mainly used in our APG and SVT systems.

The reaction of the mass, i.e. gelling resp. vulcanizing, takes place in the closed mold under pressure and temperature.

The reaction of the material in the mold usually takes place under atmosphere, whereby the injected mass displaces the air from the molding tool. If necessary, the form can be tilted or turned. For particularly complex component geometries, the mold can also be evacuated (Vacuum-APG).

Essential for the quality of the manufactured parts is a clean, even reaction of the mass from the core to the surface (i.e. the mold walls). If this is not the case, soft spots, cracks, bubbles or shrinkage cavities in the produced parts can be the result.

Depending on the respective application, the HÜBERS technology for mold filling ensures an exact filling profile and thus superior part quality by

  • temperature control of the material, if necessary continuously from the preparation
  • controlled and monitored filling speeds and internal mold pressures
  • position and number of injection nozzles
  • clamping machines with core pullers
  • rotating and/or tilting axles on the closing machines
  • clamping machines with vacuum chambers (Vacuum-APG)

Shrinkage Compensation and Pressure Control

In the processing of epoxy resins, shrinkage of the material occurs during gelation, which can lead to shrinkage cavities in the produced part. When processing liquid silicones, on the other hand, vulcanization is associated with material expansion, which can lead to the material being pressed out between the mold halves. The consequences here are waste of material and the creation of flash on the produced parts.

HÜBERS technology prevents these flaws, which are very detrimental to component quality and economy, by means of shrinkage compensation resp. pressure control units.

Crucial for these units are plungers between the static mixer and the mold, which precisely feed material into the mould (and thus compensate for shrinkage) or yield to the pressure created in the mold by the vulcanization process.

Both shrinkage compensation units and pressure control units also enable continuous filling of the mold regardless of the filling quantity.