SJ Series of Single-screw Extruder--QINGDAO TONGSAN PLASTIC MACHINERY CO., LTD,PE WATER PIPE MACHINE,PVC PIPE MACHINERY,PP/PE/PVC/PA CORRUGATED PIPE MACHINE,PPR COLD AND HOT WATER PIPE MACHINE,PP ONE-LAYER SHEET MACHINE,PVC GRANULATOR,PE/PP GRANULATOR,WPC PROFILE MACHINERY,PLASTIC EXTRUDER,PVC PROFILE MACHINE