Twin screws are divided in parallel and conical configurations.
Counter-rotating twin screw extruders have two screws that spin in the opposite direction. Also often intermeshing this style of machine is usually found in the profile, PVC or wood composite industry.
These machines typically have a much lower screw rpm and generally have much smaller L/D ratios. The screw direction allows for less shear than a single or co rotating machine.
The two styles of machines within the counter-rotating extruder category known as parallel twin screw extruder and conical twin screw extruder. A parallel twin screw has a consistent barrel diameter through the entire barrel. A conical twin screw extruder has a taper. The feed section is much larger than the end of the barrel. Both counter rotating machines with often have barrel venting. The barrels and screws of these machines are not modular so they may need to be changed for your specific application.
Base Materials:
Alloy Steel: 4140 steel(AISI 4140), Nitralloy 135M, GB 38CrMoAlA, JIS SACM645, BS EN41B, 34CrAlNi7, DIN 1.8509, DIN 1.8550, 41CrAlMo7, or equivalents.
Stainless Steel: 304, 316, 416, 17-4PH
Tool Steel: D-2, H-13, DC53, CPM 9V, CPM 10V
High Nickel Alloys: Hastelloy C-276, Inconel 625, Inconel 718
Flight Hardfacing Materials:
Nickel base: Colmonoy #56, Colmonoy #57, Colmonoy #83, Colmonoy #88
Cobalt base: Stellite #6, Stellite #12
Surface Hardenings:
Gas nitriding and Ion nitriding, Chrome plating, Carbide encapsulating, PVD coating, etc.
Machine Makes: Amut, Battenfeld, Beier, Fangli, Jwell, Liansu, Mikrosan, Milacron, Battenfield-Cincinnati, Krauss Maffei, Theysohn, Weber, etc.
Extruder Models:
Battenfeld: BEX 2-65-18V, BEX 2-65-22V, etc.
