EXCESSIVE FOAMING: Begin by checking the concentration. A mix that is too rich can contribute to foaming, just as a strong soap solution will foam more than a weak one. Check concentration with a refractometer and adjust as necessary.
Another factor that can influence the stability of foam is water quality. Coolant mixed with water or well water will break form much faster than if mixed with deionized or otherwise demineralized water.
A third factor to take into account is the possibility of mechanical problems. If there is a leak on the intake side or around the shaft seals of a coolant pump, air can be drawn in and become entrained in the fluid, resulting in a very slow-breaking layer of dense foam. The same condition can occur if the sump is run low and air is drawn into the intakes.
A fourth possibility is contamination with foam-generating materials such as cleaners that may have been inadvertently added to the sump.
Another important contributor to foam generation is the velocity and pressure at which the coolant is delivered to the cutting zone. High-pressure, high-velocity delivery generates much more foaming activity in a coolant then low-pressure high-volume delivery.
RUSTING OF PARTS: The coolant mix is too lean. Check the concentration with a refractometer and adjust if necessary.
If the pH is too low for effective corrosion control (either through contamination or bacterial degradation), check pH with paper or a meter to ensure its above 7.5. If rust occurs, immediately add 2% concentrate to sump and recheck the concentration.
Water was added alone to sump. Always add prediluted coolant to sumps.
SHORT SUMP LIFE: The concentration has not been maintained at a high enough level. Check concentration with a refractometer and adjust if necessary. Keep a coolant log with dates, refractometer reading, additions, problems, etc.
The tramp oil is sealing surface of sump which excludes oxygen and allows the rapid growth of anaerobic bacteria. Take steps to reduce or remove floating tramp oils.
Excessive contamination of the sump by dirt, fines or other extraneous materials, such as trash, coffee or cigarettes will degrade the coolant quickly. Provide filtration for coolants and receptacles for garbage.
HEAVY OR STICKY RESIDUES: The coolant concentration is too rich. Check the concentration with a refractometer and adjust with prediluted coolant if necessary.
The water is too hard. High levels of minerals can build up over time due to evaporation, resulting in hard, crystalline residues. Use treated water, such as that obtained with D.I. (deionized) or R.O. (reverse osmosis) units.
Excessive tramp oils contamination. Tramp oils can build up and coat machine surfaces. Take steps to reduce or remove floating tramp oils.
DERMATITIS OR SKIN IRRITATION: Since many factors can contribute to dermatitis in the metalworking industry, determining a specific cause can sometimes be very difficult. Some of the main factors are:
The strength of the cutting fluid solution and the consequent defatting of the skin that results from too-frequent contact with strong solutions.
The type of metal being machined may result in the presence of sensitizing elements such as nickel or chromium dissolved in the coolant.
Any grinding or metalworking process will result in small, sharp particles of metal and abrasive materials being circulated where they can come in to contact with and damage unprotected skin. Damaged skin then becomes a route of entry for contaminants and irritants, whether at work or at home.
Other causes of dermatitis can be such things as hydraulic fluids or way lubes that may find their way into a sump. These products are often designed without human contact in mind, and may contain components that can initiate or worsen a dermatitis condition.
We are always here to help! Please call us if you are having trouble with your coolants.