List of Common Hardness Testers
There are several devices used to perform this task:
- The Monsanto tester was developed 50 years ago. The design consists of "a barrel containing a compressible spring held between 2 plungers". The tablet is placed on the lower plunger, and the upper plunger is lowered onto it.
- The Strong-Cobb tester forces an anvil against a stationary platform. Results are viewed from a hydraulic gauge. The results are very similar to that of the Monsanto tester.
- The Pfizer tester compresses tablet between a holding anvil and a piston connected to a force-reading gauge when its plier-like handles are gripped.
- Erweka tester tests a tablet placed on the lower anvil and a weight moving along a rail transmits pressure slowly to the tablet.
- The Dr.Schleuniger Pharmatron tester operates in a horizontal position. An electric motor drives an anvil to compress a tablet at a constant rate. The tablet is pushed against a stationary anvil until it fractures. A reading is taken from a scale indicator.
Read more about this topic: Strong-Cobb Unit
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