Planetary
mixer
Principle
• Mechanism of mixing is shear
• Shear is applied between moving blade and stationary wall
• Mixing arm moves around its own axis and around the
central axis so that it reaches every spot of the vessel
• The plates in the blades are sloped so that powder makes
an upward movement to achieve tumbling action also
Construction
• Consists of vertical cylinder shell which can be removed
• The blade is mounted from the top of the bowl
• Mixing shaft is driven by planetary gear and it is
normally built with variable speed drive
Uses
• Break down agglomerates rapidly
• Low speeds are used for dry blending and fast for wet
granulation
Advantages
• Speed of rotation can be varied at will
• More useful for wet granulation process
Disadvantages
• Mechanical heat is buildup within the powder mix
• It requires high power
• It has limited size and is useful for batch work only