Manufacturing Vs. R&D: The Problem Is Powder Flowability

By Bob G. McGregor, General Manager, Brookfield Engineering

Tablet production depends on steady flow of powder from a feed hopper to the tablet machine. Hang ups are unwelcome because they interrupt production and manufacturing must execute a rigorous restart procedure. The blame, whether deserved or not, falls on R&D because they have responsibility for evaluating formulations for proper scale up and smooth processability. Does R&D use proper methods to assess powder flow issues? Popular techniques like the Tap Test are still widely practiced. But this is more an indicator of compaction density for the powder and not flowability in gravity discharge from a hopper. Shear cells have become the best tool for characterizing flow behavior in this particular application. Read further to find out why.