Answer: Coolant sumps that are designed to allow the coolant to move very slowly in the sump without much agitation are usually prone to this condition. The reason for the tank design is to allow the small metal fines to drop out of solution before the coolant reaches the return pumps to try and prevent sending these fines back into the cutting zone. The result is that in addition to the fines settling out on the bottom, mechanically emulsified oils from the hydraulic system, way lube, and spindle lube, are able to separate from the coolant as they are typically much lighter specific gravity than the coolant. These free oils accumulate on the surface and form a blanket of oil which is impenetrable by oxygen. The anaerobic bacteria (the kind which thrives in low oxygen environments) begins to propagate exponentially. As these organisms metabolize, they create sulfur dioxide which among other things, gives off the rotten egg smell.
2. Why does my tank smell like sour milk?
Answer: Stagnant coolant sumps which are allowed to grow bacteria often lead to an abundance of bio mass (cell tissue of dead bacteria). Under the right conditions, this will feed the growth of slime molds, water molds, and fungus. This proliferation will often lead to the sour milk smell. They begin life as amoeba-like cells. These will quickly multiply if they encounter their favorite food, bacteria. Fungi perform an essential role in the decomposition of organic matter and have fundamental roles in nutrient cycling and exchange. Many species produce bioactive compounds called mycotoxins, such as alkaloids and polyketides that are toxic to humans. Fungi can break down manufactured materials and become significant pathogens of humans and other animals.
3. Why do my coolant fluids turn darker after I use it for a month?
Answer: Most cutting operations generate a broad spectrum of solids ranging from sub micron particulate to large stringy chips measured in inches. While most systems are somewhat effective at removing the larger solids, the smaller solids are too small for most filters to stop and thus pass thru with the fluid. As they build in concentration, they will turn the color of the coolant. Additionally, micro droplets of free mechanically emulsified oils from the way lube, hydraulic, and spindle lube systems build up in the coolant causing a color change. These free oils often grab the micro fines and hold them together in small masses circulating in the coolant. In heavily contaminated sumps, biological activity will also discolor the coolants.
4. How long should I expect my coolant to last?
Answer: Coolants can last indefinitely if properly maintained. These should be considered living fluids requiring ideal conditions to continue being useful. Proper control of suspended solids, emulsified oils, oxygen levels, temperature, and makeup water ensure longer life. Using the proper chemical manager approach, the coolants can periodically be split to evaluate the water phase and oil phases for dissolved elements and chemical additive levels. Sometimes a partial dump of the coolant to reduce dissolved solids levels is required. However, properly managed, the sumps can be maintained for years.
5. How much money should I expect to spend on my filtration system?
Answer: A complete system that addresses the key elements of suspended solids, dissolved solids, free oils, coolant concentration, and temperature will range in price depending on the number of machines being fed, the flow rates required for each machine. However, it is often able to accomplish this for a single machine for prices ranging from as low as $15,000.00 to as much as $60,000.00. Typically a good filtration system will range in the neighborhood of 10% to 15% of the machine cost.
6. How big is a “Micron”?
Answer: A micrometer (American spelling m:icrometer; symbol μm; also known unofficially as a "micron") is one millionth of a meter, or equivalently one thousandth of amillimeter or one thousand nanometers. It can also be written in scientific notation as 1×10−6 m, meaning 1⁄1000000 m. A strand of human hair is about 100 μm wide Red blood cellsare approx. 8 μm in diameter.
7. How long should I expect to use my machine before I should need to clean out my tank?
Answer: While unfortunately, it is commonly accepted to have to clean out coolant tanks as often as once a month, every three to six months, or even once a year. The truth is that a properly designed system should not require to be cleaned out more frequently than once a year. Often good system designs can last for more than a year without dumping or cleaning them out.
8. What effects does PH have on my coolants?
Answer: pH is probably one of the most miss understood elements of coolant management and is still being understood in detail by the greater scientific community. pH is the measurement of free hydrogen ions in solution. Often referred to as the acidity or basicidy depending on the pH scale where a reading of 7 is considered neutral. Readings below 7 are considered acidic and numbers higher are basic or alkaline. The affects of low pH can be very damaging to the coolant additives used to lubricate the tool reduce friction, dissipate heat, and inhibit oxidation of the cutting stock.
9. Why is it harder to hold tight tolerances on my machining operations after my fluids get older?
Answer: This can be the result of many different variables but is often a combination of higher micro fines, tramp oils, and bacteria in solution which tend to collectively strip the desired additives from the coolants rendering them much like the effectiveness of cutting with straight water or worse.
10. What is the main difference between your machines and the competition?
Answer: Our systems are designed to focus on the “living fluid” environment which is intended to keep the fluid healthy for perpetual base line manufacturing. Most other systems attempt to remove the larger portion of visible solids and do nothing to address proper aeration, oil removal, temperature control, make up water quality, or coolant concentration control.
11. Can I use all types of coolant with your filtration system?
Answer: Yes. Our systems are able to be used on any type of water based coolants and can be used on straight oils as well. However, on straight oil applications with viscosity ratings above 90 ssu, the secondary filtration stages are altered and thus this needs to be conveyed at the time of request for quote and is specifically asked in our application questionnaire.
12. How long on average should it take to clean out my sump? How much down time should I expect due to sludge removal?
Answer: Unfortunately, machines don’t make a profit if they sit idle. Thus many times the proper cleaning regimen is simply not an option for the owner due to the extensive time, materials, and labor required. The proper method involves first pumping out all the coolant form the tank, removing all the lids on the tank to gain access to the main sump and then shoveling out all the solids from the bottom, using fresh water to rinse and push the remaining solids out of tight pockets and corners for removal typically by a vacuum type pump, filling the system completely with fresh water and a proper biocide and then circulating the coolant on the machine to rinse all the residual micro fines out of areas in the machine and conveyor units and get contact with all the bacteria colonies, pumping all this cleaning fluid out and refilling the unit with fresh water again and circulating it once more, then removing all this rinse water and recharging the sump with new coolant and water. Typically this procedure will take two to three men as many as sixteen hours to complete.
13. Downtime is a big problem for me, How can you guarantee that I won’t have to clean out my tanks for 12 months?
Answer: It’s simple, we have spent years developing our system approach and it has been tested and proven to work on the most demanding applications in leading industries such as large scale automotive manufacturing. We stand behind our product and will take it back if we can’t keep your tank clean!
14. How long would it take to get one of your filtration systems installed?
Answer: Typical delivery of our units runs from six to ten weeks after order and they can be installed by two men in less than one eight hour shift .