A Guide to Homogenizer Components

When selecting a laboratory-grade homogenizer research and process development scientists generally focus on the objective of the emulsifying exercise and the physical characteristics of the material being studied.  This information will guide the selection of the rotor and stator configuration.

To get the terminology straight in this post we call the rotor (attached to the rotor shaft) and the stator, attached to the shaft tube, the homogenizer generator.  It is the assembly that does the work. Various configurations are available as briefly described in our post Lab Homogenizer Rotor-Stator Configurations.

The rotor shaft, which attaches to the homogenizer drive motor, while appearing simple is in fact a rather complex assembly.  Design features are based on the material being processed. Including the rotor and stator, some designs such as the CAT G30 generator shaft have up to 16 different components.    Knowledge of these components including the correct procedures for disassembly and reassembly is important for maintenance purposes that protect your investment in the scientific homogenizer.

Key Lab Homogenizer Parts

The stationary shaft tube into which the rotating shaft is inserted is the most visible portion of the shaft-generator assembly.  Shaft tubes employed for standard emulsifying operations may have one or two ports that allow media being processed to circulate within the tube and perform a cooling function.

Homogenizer rotor shafts used for standard applications are equipped with Teflon (PTFE) bearings and discs located at the top and bottom of the rotating shaft for the purpose of keeping it centered in the stationery shaft tube.  A sealed shaft tube without ports is available equipped with two ceramic seals for processing samples under pressure, in a vacuum or for use with abrasive or adhesive type media.  It is also used if the homogenizer drive motor is used to power the DK series of flow-through chambers.  O-rings, ball bearings, springs and retaining rings are among the other shaft components in certain models of homogenizer shafts.  Detailed instructions on disassembly and reassembly using the supplied rotor and socket wrenches are contained in the CAT homogenizer tool catalog.

Lab Homogenizer Operation and Maintenance

Keep in mind that the generator rotors and stators have very sharp edges.  Use extreme caution when handling these components.  Never replace or exchange rotors and stators when the homogenizer drive motor is connected to an electric outlet.  You should also be certain that the chemistry of material being homogenized will not damage the assembly or is not flammable.  If in doubt ask a question.

We hope that the following points prove helpful:

•    Firmly attach the rotating shaft and generator tube to the drive motor.
•    Firmly attach the assembled unit to the mounting stand.
•    Never operate your homogenizer dry, as the quick heat build-up will damage or destroy shaft components such as bearings, discs and seals.
•     Position the generator assembly at least 10mm from the bottom of the vessel.  An offset will help avoid formation of a vortex.
•    Immerse the shaft-generator assembly at least 55mm to cover the bottom port and to avoid splashing.
•    Turn the homogenizer off immediately if there is unusual noise or vibration.  Check and replace generator assembly components if needed.
•    Turn the homogenizer off immediately if liquid emerges from the top generator tube port.  This indicates a leaking gasket.
•    Thoroughly clean the entire assembly after each use to avoid contaminating subsequent samples and clogging the shaft.  Refer to the operating manual or check our post on cleaning tips for CAT scientific homogenizers.

For additional suggestions on selecting and using CAT Scientific Homogenizers we invite you to download, fill in, copy and fax back our Homogeniser Questionnaire.

 

CAT Scientific

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