The key to the design of the co-rotating parallel twin-screw extruder system

The selection of the displacement coefficient of the co-rotating parallel twin-screw extruder should be based on the specific design requirements, and the displacement coefficient should be taken as a better value. Because different displacement coefficients have different effects on the contact strength and bending strength of the gears, the displacement coefficients of the gears can be all taken to be the same, which is easy to calculate in the series design, and is not prone to errors; all use angular displacement, And make the sum of the displacement coefficients greater than 0, which can improve the bending strength of the tooth root. When designing a twin-screw extruder, try to increase the number of common teeth, which is beneficial to both design and mass production.

Taking into account the strength and continuity of the series, the number of teeth and the moduli for change in the same center distance should decrease in order from large to small, and should not jump to decrease. The helix angle should make the high-speed stage take a large value and the low-speed stage take a small value, so that the axial coincidence of the high-speed stage is increased, the operation is stable, the axial force of the low-speed stage is reduced, and the service life of the bearing is improved. The speed ratio distribution should be non-integer, which is to consider that if the processed gear is defective, it will not appear in the same part of the paired gear during operation.

Minimize the sub-box surface of the transmission box as much as possible, and pay attention to the geometric dimensions of the two directions of the horizontal plane of the box body not too large. (5) The even distribution of torque and the equivalent drive of multiple drives. The uniform distribution of torque and the multi-channel equivalent drive are related to the specific transmission form, as well as the selection of gear teeth number and tooth profile parameters. At the same time, it is necessary to achieve uniform transmission of torque. Minimize drive chains as much as possible. The increase of the transmission chain means the increase of the transmission mechanism, the increase of the overall geometric size of the transmission system, and the increase of other problems.