... and better hardness PVC Skinning/Semi-Skinning Foaming Board Extrusion Line. Compared with PVC free foaming board, PVC ... free foaming board. PVC skining foaming bozrd extrusion line is composed of conical twin-screw extruder, die, vacuum calibration unit, ten ... wide application range. PVC skining foaming board extrusion line is composed of twin-screw extruder, die, vacuum calibration unit, tenhaul- ...