"Environmental and health issues have been major drivers behind the reformulation of metalworking fluids over the past 10 to 15 years," says Dr. Frans van Antwerpen, engagement manager for Kline & Co., which recently published a study about the industry. "Although significant improvements have been made during that period, these two factors will continue to drive developments over the next five years as well."
Products with reduced misting levels remain a leading area of focus for metalworking fluid suppliers, including major players like D.A. Stuart, Quaker Chemical, Fuchs Lubricants and Henkel Surface Technologies, as well as smaller niche suppliers like Hangsterfer's Laboratories and Perkins Products, according to the study. Pressure from OSHA, the United Autoworkers Union (UAW) and other organizations has prompted companies to take major steps toward meeting exposure limits for metalworking fluid aerosols recommended by the National Institute of Occupational Safety and Health (NIOSH).
Metalworking companies, including those in the transportation equipment, fabricated metal products and machinery industries, are increasingly looking to value-added synthetics, which have lower misting levels because of the absence of mineral oil and the dilute concentrations in which they are used.
"The disadvantage to these products is that the spent solutions are often difficult to separate and treat," says van Antwerpen. "So there are interesting opportunities for companies to develop synthetics that can be more readily waste-treated, such as emulsion synthetics."
Another path toward improving the health and environmental impacts of metalworking fluids is likely to be found in vegetable oil-based and synthetic ester-based formulations, according to van Antwerpen. Airborne mists of these formulations do not raise the health concerns associated with petroleum mists, and vegetable oils actually offer better lubricity than mineral oils.
The automotive industry has taken the lead in pushing the development of these new products, and Ford has reportedly written specifications for vegetable oil-based coolants. A number of issues must be addressed, however, before vegetable oil-based fluids can replace mineral oil-based products on a more widespread basis.
"Additives are less soluble in vegetable oil, and the additives have to be biodegradable to fully exploit the biodegradability of the basestock," says van Antwerpen. "More significantly, vegetable oils cost about twice as much as petroleum-based oils, and esters are even more expensive. So a supplier that can bring a more affordable product to market before its competitors should be able to achieve major market penetration."
Removal fluids that are more naturally biostable represent another goal for ambitious suppliers. Regulatory requirements for biocides are becoming increasingly stringent, complicating their use. In addition, a possible link between the popular formaldehyde-releasing triazine biocides and hypersensitivity pneumonitis has led DaimlerChrysler to proscribe the use of these biocides in the company's metalworking fluids.
"Biostable products that require minimal or no use of biocides would represent yet another major advance," says van Antwerpen, "both in terms of health and operational efficiency."
For information on how to subscribe to the studies in this series, contact Geeta Agashe at (973) 435-3484 or [email protected].