Abstract: Method to detect manmade fibres, defective fibres and/or other foreign materials in the processing of silk waste and to classify and count the faults detected in the lap of silk fibres leaving a drawing frame for instance, the method arranging that a substantially defined zone of the lap of silk fibres (20) made substantially parallel is illuminated by transparency with white light (23) and is scanned by a telecamera (24) associated with a data processing system (27) and is also illuminated by transparency with polarized light (25) and is scanned at the same time by a telecamera (26), which too is associated with the data processing system (27), images (14-15) taken by the telecameras (24-26) being processed and compared to determine the quantity, position, type and length of the faults of manmade, foreign or defective fibres.

Abstract: Method to separate polypropylene in the processing of silk schappe, whereby a lap (14) of silk fibers which are partly combed or are at least made sufficiently parallel undergoes an action of heating between 110.degree. C. and 160.degree. C. together with a simultaneous action of controlled compression so as to form clusters of polypropylene and silk fibers and thereafter an action of combing or pre-combing for the definitive removal of those clusters of polypropylene and silk fibers.Device to separate polypropylene in the processing of silk schappe, which is positioned downstream of a drawing frame (13) or analogous machine producing a lap (14) of silk fibers, the device including a conveyor means (belt/drum) cooperating with means that heat and apply adjustable pressure to the lap (14).