Different processing scenarios have varying requirements for raw material purity, production continuity, and pressure stability. Choosing an inappropriate screen changer often leads to frequent shutdowns, product scrap, or waste.

The double filter cylinder screen changer comprises a main body, two pistons (each with 1-2 filter cylinder-type screens), a hydraulic station, and other components, forming a complete filtration system. The two pistons operate simultaneously: when one is driven by a hydraulic or mechanical device for screen replacement, the other remains in melt flow. Furthermore, its unique material introduction and exhaust design ensures that screen changes can be performed without stopping the extruder or interrupting the melt flow.

The molten plastic material (1) is conveyed into the filtration chamber (2) and goes through two screens (3) facing each other. Between the two screens there are two scrapers(4), equipped with blades, which rotates to remove the impurities from the screens. The core of the scraper receives the impurities, which is then transferred to the independent discharge screw (6) then ejects it. The plastic filtered material rejoins the output channel (8) to move on to the next process.

In plastic extrusion production lines, the stable operation of screen changers directly impacts productivity and product quality. One of the most frustrating issues for manufacturers is excessive screen change frequency—frequent shutdowns to replace screens not only disrupt production rhythms and increase labor costs but also risk compromising product consistency due to pressure fluctuations.

As an efficient polymer filtration equipment, screen changers play a crucial role in plastic extrusion processing. There are various types of screen changers, such as single plate, double plate, double piston, double filter cylinder, and self cleaning screen changers, etc.