b'Occupational Safety and Health Administration This pictogram shows different hazards that workers may face, such as skin and eye irritation. MWF suppliers continue to develop products that overcome these hazards.Fight the Foam cause problems. so big, he said, but sometimes The temperature of the water- the machine sump gets overlooked coolant mix also may play a role inas far as its influence on foaming The magnesium we dont havefoaming, Fecher said. The hottercharacteristics of the metalwork-any use for, Fecher said. It is justthe water is, the greater the ten- ing fluid.a dissolved ion in the water. Thedency is to foam. If coolants areHigh-pressure delivery systems calcium, however, we have a love- above 32 C (90 F) as a machinealso can be problematic.hate relationship with. We love itruns, some ingredients in coolantsIt is typically more about the because the calcium will react withwill degrade prematurely and cre- length of time the high pressure emulsifiers that are in the formu- ate excessive foam. is on as opposed to how high the lation to form calcium crystal, andpressure is, Fecher said. Because it is the sharp edges of that cal- Mechanical Causes it doesnt give the air time to settle cium crystal that actually pop theThen there are the problems thatout of the coolant, it doesnt give bubbles of the foam. So they aid instem from mechanical issues, suchthe foam time to settle down.keeping the foam down. The hateas a low coolant level in a sump res- An additional mechanical issue portion of that is when you have tooervoir that might cause the sumpmight be laminar flow of coolant, much calcium in the water, it canpump to suck in air and very littlehe said. Coolant should flow in react with most emulsifiers and ren- fluid. Having enough real estate inas straight a line as possible, but der the emulsifier ineffective. Then,the sump is key. It normally needssometimes plumbing causes foam-what would happen is what they callto be about five to 10 times the sizeing issues.salt-out where the water will comeof the gpm rating of the pump. ThatIf you have two 90 elbows in out of the water phase. is ideal, so there is a trade-off withclose proximity to each other to These ions then can begin to con- that too, Fecher said. change direction, those can cause centrate in the pump and eventuallyYou can only make a machineturbulence,andtheturbulence 24MARCH 2020MetalworkingFluids.indd 24 2/14/20 12:02 PM'