Coolants are very imperative to the function of your machines, tool life, products and running costs.
Correct concentration of coolants is vital to correct functionality, performance and coolant life.
Refractometers are handheld, lightweight, portable instruments used to determine the concentration of water soluble fluids.
Easy to use
Refractometers are very easy to use. Just place a few drops of fluid on the prism and hold the unit up to a light source. Look into the eyepiece and read the scale.
To calibrate, just make sure the prism is clean and place a few drops of tap water on the prism. The separation line should be on zero. If not, turn the adjustment screw until it is.
BRIX Conversion to Percentage(%) Concentrate
Refractometers read on a Brix scale rather than actual percent. To get the actual percent, you must multiply the refractometer reading by your coolant’s refractive index (on product data sheet).
With most soluble oils the index is 1, so a refractometer reading of 5 multiplied by an index of 1 = 5% concentration.
However, many semi-synthetics, synthetics, grinding fluids, and some soluble oils can have a refractive index from 1.5 to 3. So a refractometer reading of 5 multiplied by an index of 1.75 = 8.75% concentration.
This is most critical with solutions designed to be run at lower concentrations which have high indexes.
Maintaining Correct Concentration
The fluid in your tank is the “working solution” and needs to be at the recommended concentration for proper performance.
Coolant concentration should be regularly monitored as various factors will impact the concentration.
A refractometer is used to quickly test the “working solution”, which can be adjusted by adding coolant concentrate or water, in order to maintain target concentration levels.