back to top
My wish lists
Save your wish list
If you want to add more content to your wish list, simply log in. If you do not have a user account, please register for the Hanser Customer Center.

» Do you already have a user account? Please log in here.
» Don't have a user account yet? Please register here.
Your wish lists
If you want to use your wish list during your next visit, simply log in. If you do not have a user account, please register for the Hanser Customer Center.
» Do you already have a user account? Please log in here.
» Don't have a user account yet? Please register here.

« Back

Your advantages at a glance

  • One login for all Hanser portals
  • Individual home page for faster access to preferred content
  • Exclusive access to selected content
  • Personal wish lists on all portals
  • Central management of your personal information and newsletter subscriptions

Register now
Deutsch
Bookmark Bookmarked
10-10-2005

Direct Extrusion of Wood Fibreboard

Extrusion line for production of thermoplastic-bonded fibreboard

Extrusion line for production of thermoplastic-bonded fibreboard

For direct extrusion of wood fibres with PP, the individual components are metered directly into the feed throat of the extruder. The resulting fibreboard has a width of 1200 mm and can be processed like wood.

Together with Pro Poly Tec GmbH (PPT), Lichtenfels, Hans Weber Maschinenfabrik GmbH, Kronach, has developed a system for extrusion of thermoplastic-bonded fibreboard (TPF). The system achieves throughputs of up to 700kg/h. The greatest fibreboard width extruded to date with this material is 1200 mm.

The TPF material consists of 80% wood fibre with 17% PP and 3% additives. The individual material components for the direct extrusion process are fed into the feed throat of the extruder via volumetric metering. Mixing of the fibre in the form of wood chips with the plastic pellets and additives occurs directly prior to entry into the feed throat. In this way, the ratios in the mixture may be varied, in contrast to processing of precompounded material.

The fibres can be added as pellets or as loose fibre. Pelletized fibres are more readily metered and permit achievement of a constant bulk density, so that a stable output results. To process loose fibres, a stuffer is required to ensure problem-free feeding while maintaining the mixture ratio. The length of the wood fibres varies between 0.5 und 1.5 mm. Not only wood fibres, but also other suitable natural fibres such as sisal, hemp, bamboo, coconut fibre, flax and straw can serve as the fibrous material. In addition to polypropylene, polyethylene and polyvinyl chloride are suitable as matrix materials. Strength, moisture uptake and impact properties can be varied through appropriate modification.

The combination die is modular in design and permits fibreboard thicknesses of 5 or 13 mm through use of inserts. The system works without calibration. The fibreboard is dimensionally stable upon exiting the die, cools to ambient temperature on a roller table and is subsequently conditioned at about 90°C. The end product can be processed like wood, but is insensitive to moisture.

Gerhard Gotzmann
gotzmann <AT> hanser.de

contact
Hans Weber Maschinenfabrik GmbH
Bamberger Straße 19-21
DE 96317 Kronach
Tel: +49 9261/409 -0
Fax: +49 9261/409 -199


Newsletter

Would you like to subscribe to our Newsletters on plastics technology and profit from the latest information?

Subscribe here

Subscribe here