Clamp Mount Mixer Guide

In the product mixing world, moving from the kitchen environment to the small industrial environment can be intimidating. The goal of this article is to take some of the mystery out of small industrial scale mixing.

What Are You Mixing?

Is the product thin like water, or thick like paint? A typical way to measure how thick a product is; is by measuring the viscosity of the liquid. The following chart gives real life examples of viscosities.

Viscosity Examples

(CPS) Approximate Viscosity

1 Water, Milk, Solvents

100 Olive Oil, SAE 10 Motor Oil

250 Castor Oil, SAE 40 Motor Oil

500 Paints, Glucose Solutions

1000 Ketchup, Glycerin, Heavy Paints

Direct Drive 1750 RPM or Gear Reduced Drive 350 RPM?

Liquid to liquid mixing is generally straight forward. Thin or low viscosity products (under 250 cps) can be mixed with either direct drive mixers at 1750 RPM, or gear reduced mixers at 350 RPM. The 1750 speed does impart more shear into the product than gear drives, so particles can be broken down a bit. If this is a problem, then select the 350 RPM gear reduced unit.

Are solids being mixed in? Do they dissolve easily? Do they get wet easily? If they do, then one can generally be less concerned, and select the mixer based on fluid viscosity above. Below 250 CPS, 1750 RPM direct drive mixers are generally chosen. Above 250 CPS, then go with 350 RPM Gear Reduced Mixers.

Note however, if solids do not mix in very well, then faster mixing is needed, and a 1750 RPM mixer is often better.

What are Tank Turns?

Some people like to talk about tank turns. Tank turn is simply Gallons Per Minute (GPM) divided by the capacity of the tank in Gallons. A 5” propeller spinning at 1750 rpm pumps about 600 Gallons per Minute. If you have a 200 Gallon tank, then 600/200 = 3 Tank Turns per Minute. Somewhere in the range of 2-3 is good for mixing! On a side note, an 8” propeller at 350 RPM also pumps approximately 600 Gallons per Minute.

Where Should I locate the Mixer?

When clamping the mixer to the tank wall, try to keep to these three rules of thumb.

First, try to locate the propeller a full “propeller’s” diameter off the bottom. If you have a 5” propeller, locate it 5” off the bottom.

Second, try to keep the propeller off center. The rule of thumb is 1/6 of the tank diameter. If you have a 30” diameter tank, then the propeller should be 5” off center.

Finally, try to keep the shaft between a 10-15 degree angle. A larger angle can harm the mixer shaft, and that would be bad!

WOW! Mystery Solved!

 You learned about fluid viscosities.

 You learned about direct drive motors, and gear reduced motors.

 You learned about tank turns.

 You learned where to locate your mixer.

Not bad for one day!