Patent ID: 6984266

Claim:
A system for the production and preparation of fibers prior to their hot-pressing to form fiberboards, comprising a refiner ( 1 ) for the milling of, chips to form fibers which then pass by steam or air pressure through a blow line ( 2 ), a tubular dryer ( 3 ), a first separator ( 4 ), a sizing device ( 9 ) and a second separator ( 6 ) into a fiber bunker preceding a spreading machine or directly into a spreading machine, the sizing device ( 9 ) being integrated into a connecting pipeline ( 5 ) to the second separator ( 6 ) and comprising a size wetting zone ( 12 ) which extends over a portion of this connecting pipeline ( 5 ) and comprises an inner pipe ( 14 ) which is provided with air passage orifices ( 13 ) and has size nozzles ( 23 ) projecting into it and a flow cross section enlarged in relation to the connecting pipeline ( 5 ) and which is surrounded by an outer pipe ( 15 ) which, with the inner pipe ( 14 ), encloses an interspace having at least one air connection, characterized by the following features: a) a fiber outlet of the first separator ( 4 ) is connected to the second separator ( 6 ) via said connecting pipeline ( 5 ), into which a blower ( 7 ) is connected upstream of the sizing device ( 9 ); b) the inner pipe ( 14 ) is designed cylindrically, the increase in its flow cross section taking place upstream of the size wetting zone ( 12 ) and a reduction in its flow cross section taking place downstream of the size wetting zone ( 12 ) from and to the initial diameter of the connecting pipeline ( 5 ) respectively, in each case via an annular cone ( 16 , 17 ); c) an upstream annular cone ( 16 ), which, like a downstream annular cone ( 17 ), is provided with air passage orifices ( 13 ), is surrounded by a ring ( 22 ) with controlled automatic injection devices, the size nozzles ( 23 ) of which project through the upstream annular cone ( 16 ) into the inner pipe ( 14 ); d) the outer pipe ( 15 ) concentrically surrounds the inner pipe ( 14 ) and with the latter defines an annular space ( 18 ) which is sealed off at its two ends and which has at least one compressed-air connection ( 20 ), from which compressed air is fed into the annular space ( 18 ) via annular compressed-air distributors ( 19 ) concentrically surrounding the outer pipe ( 15 ); e) the air passage orifices ( 13 ) of the inner pipe ( 14 ) have a diameter of about 0.1–0.5 mm.