Granulation of edge trims and refeeding them back to the extruder

Application:

Infeed of two edge trims at an extrusion line

Width of edge trims:

Thickness:

Production speed:

Material:

up to 75 mm

0,4 – 3 mm

3 – 50 m/min

ABS, PP with up to 30 % fillers

Further demands:

  • no dust pollution in the working environment
  • return of regrind to the extruder or into a material buffer
  • sound level max. 80 dB(A)

Layout of the system:

The operational safety was the primary consideration when designing the granulator. Therefore the granulator RS 3004 (cutting diameter 300 mm, cutting width 414 mm) was equipped with following features:

  • two separate infeed systems with regulation of infeed speed
  • sound insulation of granulator
  • suction unit working in negative pressure
  • change-over valve to extruder or material buffer
  • forced feeding of the regrind direct into the flow of virgin material above the extruder screw; thereby no demixing of virgin material and regrind
  • cartridge filter for transport (exhaust) air