User:Trex4321/sandbox/Co-rotating twin screw extruder

Co-rotating twin screw extruders are a type of extruders used for compounding of plastics and pharmaceuticals, devolatilization of polymers , food processing , production of masterbatch , reactive extrusion and other tasks.

Working principle
Co-rotating twin screw extruders consist of two screws situated in a barrel which turn in the same direction at the same speed. The basic geometry of these machines is self-cleaning: In a pair of screws, one screw wipes the other one, and the barrel is wiped by the tips of the screws.

Quantities of the whole machine
Twin-screw extruders are characterized by
 * Barrel diameter $$D$$
 * Centerline distance $$A$$
 * Total length of their process section $$L$$, which is usually flexible
 * Maximum permissible torque per shaft $$M_{max}$$
 * Range of turning speed $$n$$

Extruder processes in twin screw extruders can be characterized by the following characteristic numbers:
 * Volumetric throughput $$\dot V$$
 * $$q=\frac{\dot V}{n D^3}$$