W Mixer
The Dray W Mixer (pat. 3788612) is a simple, time tested, high shear dispersive mixing device. Similar to the SW mixer, the W mixing design was developed to have a screw design that was high shear and self cleaning while providing excellent dispersion. The W Mixer has been used in hundreds of real world applications, primarily in extrusion, for almost 45 years.
How the W Mixer Works
The polymer enters tapering inlet grooves. As the inlet grooves taper and terminate, the polymer is forced over the undercut flights into outlet grooves. The tapering inlet and outlet grooves form geometry similar to a "W".
The small clearance between the undercut flights and barrel wall imparts high shear forces to the polymer. Any remaining solids or agglomerates after solid bed break up are elongated, increasing surface area exposed to the adjacent melt.
The W Mixer has been used in hundreds of real world extrusion applications. This high shear, dispersive mixing design is typically paired with our MFV (multi-flighted vent) design in multi-stage vented operations.
Vented Extruder Operation
The W Mixer has been used routinely in vented operation in conjunction with the MFV (multi-flighted vent). Vented operation requires successful melting within the first stage to ensure proper venting and output. The high shear W Mixer promotes excellent dispersion and melt uniformity.