Convergent flow analysis in the extrusion of wet powder masses.

The angle of convergent flow which occurs when a wet powder mass is extruded through a die has been assessed by the inclusion of dyes in the mass before extrusion. The angles obtained are dependent on the powder components and their proportion, the moisture level, and the ratio of the dead space to the area of open die. The method allows assessment of the type and ease of flow which occurs during extrusion.