Study results produced on Gamlen R series (formerly Gamlen Tablet Press) are scalable to high speed Fette production press

Comparison of 100mg of two particular formulations (obtained from a major pharma company) compacted on the Gamlen Tablet Press (GTP-1) showed matching results when compared with production data obtained on a high speed rotary tablet press (Fette 2090)

Analysis of tablet tensile strength to compaction pressure and solid fraction demonstrated that the results obtained on the Gamlen Tablet Press (GTP-1) can be reproduced for different sizes and shapes of tablets produced on a rotary press.

DC scalebility











The GTP-1 produced 100mg round flat tablets whilst the Fette 2090 produced 800mg oval shaped tablets of the same formulation.

The tensile strength was calculated using the solutions in the USP32-NF27:monograph 1217

For flat face (1) and for oval shapes (2)

(1)                                                              (2)

Flat Face Tensile Strengthoval shape


WG scaleability
















Solid fraction was calculated from the ratio of the tablet density / true density of the formulation. This indicates the ratio of air to solid in the tablet.

For these two formulations it appears the tablet tensile strength made by the GTP-1 using mg quantities of material are reproduced at the production scale with a rotary press. This is the first time scaleability to a rotary press has been shown using the GTP-1 and will revolutionise the tablet development process speeding up the pre-formulation, formulation and process development process. In addition it provides an excellent approach to troubleshoot tablet manufacturing issues such as capping and high ejection forces using milligram quantities of material.











Why use a Gamlen Tablet Press?

It can save you time, money and materials. People need help to study tablets under properly controlled conditions in a laboratory.

Michael Gamlen invented the Gamlen Tablet Press (GTP) to help you understand the relationship between the properties of your drug, formulation, and manufacturing process. When you do this you can develop better products more quickly, and improve productivity of your tablet manufacturing operations.

The GTP is the first instrument designed to make tablets on a small scale at a user-specified compaction force. This force determines both the physical strength and the dissolution behaviour of the tablet. These are the key properties which ensure the tablet reaches the patient and delivers the drug.

The machine works by monitoring the force in real time using a PLC.  The punch force and punch position are displayed in real time on a computer which is also used to input the compaction conditions. Using the GTP we make tablets of extraordinary reproducibility and consistency, within 1-2% force, and with no wastage. Batch yields are >99%.

For the measurement of tablet breaking load, the press records both force and displacement during both compression and fracture, and also provides the ejection force profile associated with tablet ejection

In the scale-up of tablet production, the press can be used to determine the relationship between tablets developed at the bench-top scale using a few grams of material (often at the early development stage) and the final tablet manufactured on a rotary tablet press. The latter uses hundreds of kilograms of material, making process development difficult because of practical difficulties in experimentation; smaller and different shaped tablets can, however, be scaled to the final desired tablet design if TFS is used as the basis for comparison.

If you want better tablet products and processes you need the Gamlen Tablet Press.

Have a question? Like a quotation?
Like to see a Gamlen Tablet Press demo 
or have batch tablet samples made?

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