APPARATUS FOR REDUCING VOLUME OF PLASTIC FOAM

摘要

PURPOSE:To efficiently reduce the volume of a waste material of plastic foam of every kind by simple equipment, in the screws of a twinscrew extruder, by providing protruding parts between the spiral fins of a charging part and forming the leading end part of each of the screws into a taper shape whose cross-sectional area becomes large toward the leading end part. CONSTITUTION:Spiral fins 5 are provided to the surfaces of two screws and two or more protruding parts 7 are provided to the surface of the charging part 6 below a supply port 4 between the spiral fins 5 in almost parallel to the axial direction of the screws. Supplied foam is carried to the space between two screws by the rotation of the protruding parts 7 to be cut by the fins 5. A compression part 8 makes a cylinder and the screws almost parallel and volume reducing parts 9 are provided to the leading ends of the screws so as to be formed into a taper shape whose cross-sectional area becomes large forwardly and to rub the cut foam particles with each other to reduce the volume thereof while defoaming them. This apparatus can be adapted to all of plastic foams but shows large effect to polyolefinic foam having high strength.