What to Consider When Selecting a Laboratory Mixer

Are you mixed up about what type of mixer you need for your application? We can give you a few pointers. Mixers come in a variety of types, with accessories to help you achieve the mixing quality desired for your application. Laboratory mixers are available with at least three kinds of motors as well as various mounts, impellers, and paddles. When selecting a laboratory mixer for your application, consider the following:

• Horsepower (hp)
• Speed (fixed or variable)
• Type of impeller
• Impeller diameter
• Batch volume
• Viscosity (cps) of your sample
• Specific gravity or lbs/gallon of your sample mixers

Guidance on Specific Applications

For mixing food and beverage items:

• Tend to be high viscosity applications
• High shear/low speed
• Need sanitary and ANSI connections; 316 Stainless Steel shafts
• QA documentation is important for FDA audits, especially ISO documentation

When mixing two miscible fluids, use:

• Offset angled mount
• High flow impeller
• Axial flow
• Vortex undesirable (use baffles if center mount)

For paint pigment dispersion:

• Center mount mixer
• Vortex is desirable
• High shear/high flow/dispersion impeller
• May need higher direct drive speeds

When dissolving light powders:

• Center the stirrer to create a vortex
• Reposition the stirrer at an angle to maintain a uniform suspension or to blend in other fluids
• High flow impeller

Note: portable clamp mount mixers make repositioning easy and you may want more than one stirring action for multi-step mixing

To maintain uniformly blended suspension:

• Offset angled mount
• High flow impeller
• Axial flow
• Vortex undesirable (use baffles, dual impellers)

For more help with selecting a laboratory mixer for your application, contact our application specialists at 1-800-323-4340 or visit the Cole-Parmer website