Influence of teardrop studs on rotating frictional base plate on spheroid quality in rotary spheronization

The effects of teardrop-shaped studs on the quality of rotary processed spheroids were investigated. The spheroids were produced under similar conditions using three rotating frictional base plates with teardrop studs of different height, volume, cross-sectional area and surface area. Spheroid properties were rated by size, size distribution, shape, friability and density. The amounts of lumps and fines produced, and the adhesion of material on the rotating frictional base plates was also looked into. The dimension of the teardrop studs on the rotating frictional base plate affected spheroid quality. The resultant shear forces and energy input during rotary spheronization differed depending on the different height, volume, cross-sectional area and surface area of studs. With the increase in height, volume, cross-sectional area and surface area of studs on the frictional base plate, the mass median diameter, e_R and circularity of spheroids increased with corresponding decrease in span, lumps and fines. Although the frictional base plate with shortest studs had little adhesion, it may not supply enough shear force and energy input for the spheronization process, resulting in a less stable process. A balance between energy input and adhesion on the rotating frictional base plate was needed in order to optimize the production of spheroids by rotary processing.