Production of fibre-reinforced plastic mouldings or coatings involves mixing e.g. chopped glass fibres with polyurethane starting mixture in a special mixing system and spraying directly onto a substrate

摘要

A method for the production of fibre-reinforced plastic mouldings or coatings by injecting chopped fibres into a reactive, liquid mixture of plastic starting materials and spraying the mixture directly onto a substrate, involves using a system in which an inner tube carrying the reaction mixture ends flush with the outlet of a chamber carrying the fibres. A method for the production of fibre-reinforced plastic mouldings or coatings (I) involves (a) chopping fibre rovings to a length of 3-100 (preferably 5-15) mm, (b) feeding the chopped fibres (II) into and through a chamber via a feed pipe, (c) simultaneously feeding a reactive, liquid mixture (III) of plastic starting materials through a tube mounted inside the chamber and ending flush with the chamber outlet (this mixture may optionally be produced in a preceding mixing chamber or in a mixer mounted inside the inner tube), (d) mixing (II) with (III) directly after the outlet and (e) spraying the final mixture onto a substrate. An independent claim is included for a device for this method, comprising (a') a chamber or outer tube with a tapering outlet and a lateral branch situated before the outlet for connecting a feeder piper for fibres (II) under gas pressure, (b') a tube inside (a') for starting materials, as described above, (c') feed line(s) for fibre-containing pressurised gas, with a built-in feeder system for the gas carrying the chopped fibres from the chopper to the connecting branch and (d') a fibre chopper connected to the feeder system.