The main part of the pin screw is a common screw. The pin can be arranged in the drop slot of the melting section or the metering section of the screw rod or on the smooth cylindrical surface with no screw groove at the end of the metering section. Pin arranged by a certain arrangement, density can vary, the number varies. The cylindrical pin is formed by fitting the pin into the hole of the screw; the square or diamond pin is formed by milling directly on the screw.
If these pins are set in the melting zone, the pin can break the solid bed, destroy the two-phase flow, and stir the solid and liquid phases together to increase the contact area between the solid solution phase and the contained material and promote Melt. If the pins are located in the melt delivery zone, their main function is to divide the stream, increase the interface, change the direction of the stream, and rearrange the stream. Repeatedly diversion, confluence, changing the flow direction, the melt composition and temperature homogenization.
Mixing section are set in the screw end of the ordinary screw section of the inward slotted structure, the outer diameter and the outer diameter of the screw equal. Grooves are divided into several groups, each group is the convergence of materials. Material is divided by the trench, to the convergence zone meeting, re-segmentation, convergence, the principle is similar to pin-type.
Separate screw is characterized by the melting section in addition to the original a screw thread (known as the main screw), but also attached a thread (called the additional thread), the outer diameter slightly smaller than the outer diameter of the main thread, Different lead, deputy thread from the end of the feed section (and here associated with the feed section), after several threads, gradually and the main section of the homogenization section intersect.
The screw thread groove depth and thread lead from the beginning of the feed section to the end of the homogenization are gradually changing, both the thread lead gradually narrowing from the width, the depth of the screw groove gradually lightening, the material can be the maximum compression.