The venting extruder is quite different in design and function from the non-venting extruder. The venting extruder has one or more openings (vents) in its barrel from which volatiles can escape. thus. The venting extruder continuously removes volatiles continuously from the polymer. This venting adds a function that is not available in non-venting extruders. In addition to the venting of volatiles, certain components, such as additives, fillers, reactive components, and the like, may be added to the polymer using a vent. This obviously increases the versatility of the venting extruder and has the added benefit of venting the extruder as a conventional non-exhaust squeezing as long as the vent is blocked and the screw geometry is changed where possible. Out of the plane.
Figure 1.2 Basic structure of the exhaust extruder
The design of the screw is critical to the proper operation of the venting extruder. One of the main problems that plague the exhaust extruder is the vent overflow. In this case, not only the volatiles are released through the vent, but also a certain amount of polymer flows out. Thus, the extruder screw must be designed so that there is no positive pressure in the polymer under the vent (exhaust section), which leads to the development of secondary extrusion screws, especially for venting extruders. Secondary extrusion screw. The secondary extrusion screw has two compression sections separated by a pressure relief/exhaust section. This consists of two single-stage extrusion screws similar to each other connected in series along one axis.