Single-screw extruders are continuous, high-pressure-generating pumps for

viscous materials that can generate thousands of pounds of pressure while

melting and mixing. These devices are most often fed by pelletized solids with

a regular geometry, such as spheroids and cylinders. Less common, and with

somewhat greater difficulty, the feed may be diced material, powders, granulations, flakes, taffy, slurries, or melted material.