the axis-to-axis distance of single screw extruder
The axis-to-axis distance between Single Screw Extruder the left and right sets is constant, and the left and right kneading are completely meshed with each other. Looking at a certain section, therefore, when one kneading blade of the right kneading rotor, which has the greater tip clearance, is in a horizontal position, In the conventional construction described above, however, since the kneading sheet production extruder and Twin Screw Extruder are formed so as to allow the kneading rotors and to completely mesh with each other, the sectional shapes of the kneading rotors and are not in match with those of the kneading disks and More specifically, gear pump, On the contrary, when the other kneading blade of the right kneading rotor, which has the smaller tip clearance, is in a horizontal position.
A relatively thick belly portion of the opposite left kneading rotor is positioned in an opposing relation. in the arrangement that the left and right kneading rotors are completely meshed with each other and the kneading blades of each rotor are formed to provide different tip clearances, therefore, assuming the sets to be cut at a certain section, the sectional shapes of the left and right kneading rotors are asymmetrical and hence not the same on the left and right sides. Stated otherwise, looking at one set, the sectional shape of the kneading rotor is changed in the axial direction thereof.
Supposing now, as described above, that the sectional shapes of the left and right kneading rotors are changed in the axial direction thereof so as to allow both the kneading rotors to completely mesh with each other, i.e., that the left and right kneading rotors are formed to have the sectional shapes asymmetrical on the left and right sides, if two adjacent segments in the axial direction of et have different sectional shapes from each other, two adjacent segments in the axial direction of the other set, which are respectively in mesh with the former two adjacent segments, also have different sectional shapes from each other. This means that, among four segments of the left and right sets, pairs of which are opposed in the transverse direction and adjacent to each other in the axial direction, each pair of segments in an obliquely opposing relation are not properly meshed with each other. In other words, the segments of both the sets, which are in an obliquely opposing relation and should not be meshed with each other in a proper setup condition, are positioned side by side in the transverse direction at connecting portions between the axially adjacent segments of the sets upon a slight shift in the axial direction, and then interfere with connecting portions because of the left and right kneading rotors having different sectional shapes.
Thus, if two adjacent segments of each set in the axial direction have sectional shapes different at a connecting portion between the segments, the left and right rotors interfere with each other at the connecting portions upon a slight shift (relative movement) of the left and right rotors in the axial direction thereof Therefore, the related art requires a spacer to be inserted in the connecting portion between every two axially adjacent segments of each set. The spacer has a thickness enough to absorb such a slight rotor shift in the axial direction, and also has a sectional shape selected such that the spacers arranged in an opposing relation are prevented from Single Screw Extruder interfering with each other due to their sectional shapes.