STUDIES ON POWDER PLUG FORMATION USING A SIMULATED CAPSULE FILLING MACHINE

Using an apparatus which simulates the action of a Macofar 13-2 dosati ng-type capsule-filling machine, the variation in plug weight and dens ity with changing machine parameters has been studied. The piston ejec tion speed has no effect on plug properties. However increase in compr ession speed leads to a less consolidated powder plug and hence reduce d plug weight. Application of higher pressures reduces plug weight cha nges, but would be expected to affect release characteristics. Compari son of axial and radial pressures generated by plugs of Starch 1500 an d lubricated lactose show significant differences which can be explain ed by the different consolidation and elastic properties of the two so lids.