Caleva Wet Mass Mixer Torque Rheometer

The Caleva Mixer Torque Rheometer (MTR)

General Description:

The Caleva Mixer Torque Rheometer provides a quick and easy way to quantitatively measure a wet mass in terms of the torque produced when shearing the wet mass within a mixing bowl.

The MTR has applications for research, formulation/process development and process scale up studies. The MTR is also a useful apparatus for off-line monitoring of production excipient screening and quality control.

The Caleva MTR is designed to provide a robust practical rheometer suited to both laboratory and production/quality control environments. The instrument is rapid in use, simple to operate and generates accurate, reproducible results providing an objective, efficient and precise quantitative description of the wet mass.

In Short, the instrument has potential wherever wet masses are used and particularly in the pharmaceutical industry, food processing and baking, cosmetics, pesticide, and agricultural and chemical industries.

The MTR offers three type of :

The MTR has three (3) experimental formats which are called:

1. Consistency
2. Variable Mix Time
3. Multiple Addition Test

Within each of these three formats, the details of each experiment completley configurable to meet the user‘s needs. The MTR’s three experimental modes are described below.

 

1. Consistency Test:

The consistency test is used to verify the properties of wet powder masses produced in a larger mixer/granulator system. It simply measures the torque of the mixer blades when mixing a wet mass for a short period of time. It may be used as a quality control tool or as part of a scale up strategy to predict mixing end points. At the beginning of the test the MTR measures the torque of an empty mixing bowl. A small amount of material is added to the bowl and mixed for a short time to ensure homogeneity before the senond torque measurement is taken.

2. Variable Mix Time:

As with the other experimental modes, the variable mix time experiment begins with a baseline measurement of the torque with an empty mixing bowl. Dry powder is added and again the torque is loged. Then all of the the binder is added at once and the torque is logged at user-defined intervals for a period of time.

This experimental mode is useful for analyizing the effects of mixing time alone on a material.

3. Multiple Addition:

This experiment is used to provide an estimate of the optimum binder ratio for a given formulation. “Optimum” meaning the binder ratio at which the Mean Line Torque, and therefore the consistency, is at a maximum value. Wet masses usually exhibit an increase in torque with an increase in binder content up to a miximum value and decreasing as the mass becomes a slurry.

After the baseline torque is measured with an empty bowl, dry powder is introduced on to the mixing bowl and the torque measured. A binder is then incrementally then added to the mixing bowl and the torque is logged at user defined intervals.

This experimental mode is very useful for determenining the optimum binder ratio, that is the ratio of liquid binder, (usually water) to powder using only a small amount of material.

 

Advanced features:

The Caleva MTR has a advanced features to make it a easier to compare and and analyize data gleanded from the experiments.

Comparison of Experimental Results:

The ability to compare experimental different results is probably one of the most powerful features of the Caleva MTR. A user can select a number different experiments and display the results on a screen or report. A legend to the right of the graph is provided to distinguish the different plots.

 

Advanced Analysis:

Sometimes it is necessary to “massage” the data in order to compensate for “noise” in the system and to allow for differences in homogeneity of the materials being tested. For Advanced Analysis, the MTR provides “Smooting” and “Sensitivity” factors which can be applied to the raw torque measurements in order to obtain torque curves which are close to theoretical ideals.

 

 

 

 

 

Report Generation and Export to MS Excel ^®:

The Caleva Mixer Torque Rheometer provides the user the ability to print the graphs and tabular data on a printer. The user also has the ability to export the CSV data to an Excel^® spreadsheet for further analysis.