... screw 3,PVC control system USAGEThis PVC free foaming board ,skinning foaming extrusion line is composed of special twin-screw extruder , ... has the features of high output ,stable extrusion ,high foaming ,smooth and wearable surface,Equipped with printing machine ,laminating ... on-site installation and testing machines involved in washing line. 5. Meanwhile technicians will give free training lessons ...