What are the classifications of screen changers for plastic extruders?
Plastic extruder screen changers can be roughly divided into two categories: continuous screen changer and discontinuous screen changer
The first category: continuous screen changer, which can be changed continuously, automatically, without stopping the machine, without instantaneous interruption of material flow. The mesh belt type automatic screen changer belongs to this category. It is automatically controlled by the control system for heating and cooling, and the screen is flexible. It is a supporting screen changer for the production of high-quality and long-process products such as cast film, coating, wire drawing, pipe, chemical fiber spinning, plate, sheet, and granulation, especially suitable for the production of high-precision products that have strict requirements on pressure fluctuations .
The second type: non-continuous screen changer, the melt flow (or instantaneous) is interrupted when the screen is changed or the machine needs to be shut down to change the screen. There are many types of this type of screen changer, and the more typical ones are: manual screen changer, Single plate hydraulic screen changer and so on. The material flow of the non-continuous screen changer will be interrupted instantly, and it cannot realize continuous operation in the true sense. It is only suitable for products with large fluctuations in extrusion volume, low precision, and lax quality. For products with high quality requirements such as flat yarn, monofilament, agricultural film, salivation film, lamination film, lamination film, sheet, etc., even The extrusion process will not be completely interrupted, and the product will leave imperfections.
