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