1,Standards of single screw and cylinder of exturder machine:20mm--300mm, 2,Ratio of length to siameter :L/D= ... --55 1,Standards of single screw and cylinder of exturder machine:20mm--300mm,2,Ratio of length to siameter :L/D ... (HTP1:abrasion HTP2:corrosion resistance,HTP3:abrasion and corrosion resistance) Barrel for plastic extruder machine