1. SJ-series single-screw extruder machine 2. SJSZ-series conical double-screw plastic<br /> extruder machine 3. PP-R /PE /PVCpipe extrusion line 4. PE big-diameter pipe extrusion<br /> line 5. Random polypropylene(PP-R)pipe production line 6. Production line for double-wall<br /> spiral big-diameter plasti