... 3.Processed to our drawing or OEM. Techincal Advantages of PVC extrusion double screw and barrrel/parallel twin screw and barrel :1 ... and etc. Meanwhile,Used for PVC + 30% CaCo3, recylced plastic material,etc co-rotating PVC extrusion double screw and barrrel/parallel twin screw ... .4. Parallel twin-screw and barrel is successfully applied in PVC plate, pipe, profile, pellet and mould, at the same time ...