The principal functions of water-soluble cutting fluids are cooling (dissipating heat generated in the operation), lubrication (reduce friction between the tool and the job) & flushing (remove chips or swarf away from the cutting zone). EHS has always been a prime focus in the metalworking industry hence metalworking fluids have constantly changing chemistries.
The emulsions (oil in water) have been there for decades in the form of mineral oil-based, vegetable oil-based and the recent past semi-synthetic oil-based. Mineral-based have poor flushing and emulsion stability. Vegetable-based have poor oxidation stability. The major challenge in running soluble oils is biological. The presence of oil, nutrients & water at a conducive temperature paves way for bacteria formation in the system. Hence, the pH drop & smell issues. The semisynthetic products use high alkalinity and pH to control this aspect, but the counter effect is skin allergies/skin irritation & lot of foaming issues. For good lubrication and tool life, most of these products use chlorine (chlorinated paraffin) which is now internationally prohibited because of severe EHS concerns.
X-COOL® water-soluble cutting fluids are based on NANO EMULSION TECHNOLOGY. These nanoemulsions are thermodynamically stable compared to the conventional fluids that are only kinetically stable emulsions, which will separate into oil and water over time. The nanoparticle size of X-COOL® nanoemulsions ranges from about 10–300 nm. Because of this small particle size, there is a drastic reduction in carryover losses. High wetting & rinsing properties enable quick & stable build-up of chlorine-free EP additives layer at a microscopic level to improve tool life and surface finish. These emulsions appear transparent or translucent, which helps visibility during operation. The stable pH of these products does not cause skin irritation and does not require harsh chemicals to control microbial activity. The X- COOL® series provides high biostability even at low concentrations, producing sterile bacteria-free solutions and emulsions with a long sump life. Also, DM or DI water is not a compulsion, as X-COOL® water-soluble cutting fluids can work in both soft & hard water without any foaming.