Advantages of single-column backflush hydraulic screen changers: ·Allow for consistent running for a long time. Neither downtime nor significant waste of raw materials during the production cycle occurs thanks to avoidance of frequent screen changing; ·In the process of flushing, only negligible pressure fluctuation will occur to the melt flow of the system that will have little impact on production. ·Under normal working conditions, the system allows for a double filtration area to enable higher work efficiency. ·The control unit of the system is mounted on the control cabinet of the supporting hydraulic system , contributing to higher safety performance. The stroke is under the control of high-precision electronic caliper which can vary the stroke of screen piston precisely through corresponding control modules. The screen change-over duration for the double-position quick screen changer ?seconds. The filter area is optional from ¢30 to ¢250mm The four-position dual-column screen changer enables non-stop screen changing and has filter area twice larger than that of single screen, especially fit for high-capacity extruding line which can extrude 500-2000 kg per hour. The screen changer is applicable for almost all polymer medias, including PC 〿PMMA 〿PET 〿PS (and similar thermoplastics).