PLUG SCREW FEEDER FOR FEEDING CELLULOSE PULP/CHIPS

摘要

A screw pipe unit (110) intended to cooperate with and at least partly enclose a screw (120) in a plug screw feeder (100) for cellulose chips/pulp is provided. The screw pipe unit comprises a plurality of openings (116) for filtrate dewatered from chips/pulp in the screw pipe unit when the plug screw feeder is in operation. The screw pipe unit is, on at least a portion of its inner surface (112), provided with bars (114-2) inclined with respect to the longitudinal axis (L) of the screw pipe unit. The inclination of the bars decreases in the longitudinal direction, from a first portion (110a) of the screw pipe unit with maximum inclination to a second portion (110b) of the screw pipe unit with bars substantially parallel to said axis, the second portion being further away from the inlet end of the screw pipe unit than the first portion.