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Press Review Tierfutter

La Meccanica’s expanders

Thanks to the expander, it’s possible to add high amounts of greases and oils in the formula, still obtaining a high quality pellet.

Thanks to the expander, it’s possible to add high amounts of greases and oils in the formula, still obtaining a high quality pellet (PDI 97%-99%). Several analyses as well as empirical data, in fact, show that only using the expander you can achieve ranging from 1.5% to 3% at full load of the pellet mill, while without it's possible to produce commercial pellets out of these mixtures. Pellet hardness and fine ratio can be exactly controlled by adjusting the die with piston in the expander. The ground and expanded material can also feed directly without pelleting, by-passing the pellet mill, which is an appropriate method to produce a structural feed meal for layers.

The main drive of La Meccanica’s expanders has a hydraulic coupling, with built in torque overload and v-belt drive transfer. The heavy-duty compression screw is constructed out of several sections on a single shaft, increasing shear action.
The die assembly can be hydraulically turned or disconnected from the machine for easy access and its aperture is hydraulically controlled allowing operator to remotely increase or reduce compression and shear action and the extrusion and molding of the final product. Variable speed knife arrangement, with independent drive, determines crumb size and ensures uniform product size.
Thanks to many special injectors, it’s possible to add steam under high pressure and additional liquids through the length of the expander. The automatic control allows operator to preset parameters and the system can fine tune accordingly. Finally, flexibility, due to the number of inlet points and short build up time, allows the system to stop/start without problems.

expander drawing

Technical features of La Meccanica’s expanders

Expander type  Total lenght  Screw  Screw speed  Barrel lenght  Output T/h Drive kW
STHT 230  4120 230 300 1300 5-12 110-132
STHT 305 6700 305 230 1500 12-20 160-200
STHT 305 compact  3900 305 230 850 12-20 160-200





Our expanders are supplied with:

  • drive/power transmission
  • charging hopper
  • screw for compression and homogenizing
  • independent head section with fully adjustable flat die arrangement
  • multi blade with variable speed knife arrangement that cuts the material into uniform crumb