Managing risk for manufacturing workers and the environment means balancing the benefits and hazards associated with metalworking fluid formulations and processes. Achieving this balance has motivated multiple significant shifts in formulations over the years. Change may once again be on the horizon for the metalworking fluid industry as the United States Environmental Protection Agency reviews the risks and safety of a widely used family of biocides, while a major automotive manufacturer has plans to increase its use of machining techniques that significantly reduce consumption of coolants.
An estimated 80% of the metalworking fluids market consists of emulsifiable oils, semi-synthetic and synthetic products, collectively referred to as water-miscible metalworking fluids. These mixtures of water and hydrocarbon base stocks, enhanced by phosphorus-, nitrogen- and sulfur-containing additives, provide diverse nutrients that enable bacteria and fungi to thrive. Biodeterioration can include formation of biofilms or slimy deposits on surfaces of tanks, pipes and other equipment. Biofilms plug filters, interfere with fluid flow and cause corrosion and other problems.
Biocides prevent microbes from causing biodeterioration that alters the chemical composition and performance properties of metalworking fluid products during storage, in use and in sumps.