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Have you had challenges with CM adhesion/cohesion? Experts are discussing this topic in the Oral Solid Dosage Group,, broken out into the following key areas: conveying, feeding, transfer hoppers, and transition pipes. Learn from their experience by reading the full conversation here:

Non-invasive, continuous, quantitative detection of powder level and mass holdup in a metal feed tube

By Louge, Michel Y; Mandur, Jasdeep; Blincoe, William; Tantuccio, Anthony; Meyer, Robert F

Published on CMKC


We describe a quantitative, non-invasive capacitance detector providing a rapid signal that varies continuously with powder level and/or mass holdup in the metal feed tube of a tablet press. We outline the principle of its processing electronics, provide an algorithm for the accurate interpretation of its signals, pose general design guidelines for embedding the instrument in the tube, and show how the detector can be paired with another non-invasive reference probe to operate with varying powder blend and moisture. We illustrate a control strategy that keeps powder level constant with a process example.


Powder Technology. Volume 382, 2021, 467-477



Type of publication

Peer-reviewed journal


  • Cornell University
  • Merck & Co., Inc

Article Classification


Classification Areas

  • PAT
  • Oral solid dose