Counter Rotating Parallel Twin-screws

Twin-screws and Barrels for Parallel Twin-screw Extruders


Harden Industries’ counter rotating parallel twin screw and cylinder focus is on providing high surface area and low shear screw designs that will optimize the homogeneity of the melt, maximize the productivity of the extruder, and provide long lasting life for both the screws and barrel. Carbide coating hardening of screw flights is also available.

Twin-screw Extruder

Harden ‘s counter rotating conical and parallel twin screws and barrels provide long lasting life for both the screws and barrel. We have been supplying conical twin-screws to many of the major PVC twin screw extruder manufacturers in China and our products have been used around the world as a good alternative of low cost replacement parts.


Screw & Barrel Ranges for Single Screw Extruder

Screw Diameter50mm -180mm
 Screw LengthL/D ratio 16 – 35

Screw Technical Specifications

Steel MaterialDIN 41CrA1Mo7 / AST M4140 / GB 38CrMoAlA, 9Cr18MoV
Heat TreatmentTempered and nitride, nitride depth: 0.5 mm – 0.7
    Surface hardness:HV900 – HV1, 000
    Special treatment:Carbide coating (screw flight) and bimetallic barrel
Screw straight tolerance0.015 mm/m
Surface roughnessRa 0.4μm