Page 38 - MetalForming Magazine May 2023

THE PATH TOWARD
OIL-FREE
METALWORKING
FLUIDS
Metalworking fluids in general use less oil than they used to, but cost factors and a lack of effective water-soluble additives for high-demand applications keep oil in the picture for now.
This article is a condensed version of The Long Road Toward Oil-Free Metal working Fluids, which appeared in the August 2022 issue of Tribology & LubricationTechnology(TLT),theoffi- cial publication of the Society of Tri- bologists and Lubrication Engineers, www.stle.org, and was written by Dr. Nancy McGuire, a contributing editor for TLT.
How far can metalworking-fluid (MWF) formulators push the trend toward less mineral-oil content—and less oil content of any kind? Over the past couple of decades, newer formulations on the market have trended toward less dependence on nonrenewable resources such as petro- leum products and fewer ingredients such as biocides that pose worker- health concerns.
Oil-free formulations check these boxes, and help with reducing foam, increasing fluid life and eliminating the need to clean oil films from finished workpieces. However, these formula- tions don’t work for all applications, can be expensive and can present
waste-disposal problems. Here’s what several industry experts have to say about oil-free MWFs.
Oil-Free Fluids: Trends and Drivers
The drive toward fully oil-free fluids depends on applications and customer needs, including local requirements and policies, says Bridget Dubbert, technical director at Engineered Lubricants, a manufacturer of MWFs and other prod- ucts. Corporate initiatives toward more sustainability also can drive a change in the fluids used, although this tends to be more prevalent in larger opera- tions. Smaller companies, Dubbert adds, focus on products that work, that pres- ent the fewest problems and that keep costs under control. Oil-free MWFs are on the market and being used success- fully, but in some instances, users can find pricing to be a hurdle. For faster, light-duty operations where cooling takes precedence over lubrication, these fluids are ideal.
“We’re not quite there yet for many operations that need a high degree of lubrication,” Dubbert says. “Heavy-
duty stamping and drawing will be the last holdouts, I believe.”
The past 5 to 10 yr. have seen a more focused attempt to bring sustainable compositions into industries in general, and compositions from industry sec- tors at the leading edge of this trend often find their way into other sectors.
Manufacturers with operations that directly affect the environment or con- sumer safety—marine or food-industry lubricants, for example—may ease their way into synthetic lubricants, adopting them for some percentage of their operations. As these manufactur- ers begin to see increases in fluid lifes- pan, fewer price fluctuations tied to petroleum prices or other advantages, they might decide to increase that per- centage. As synthetic lubricants become established in these markets, they could more easily enter into others as well.
Petroleum-based fluids remain affordable, and customers tend to stay with what works well for the price. Quantifying the overall benefits of going green proves difficult due to the many interacting factors that con-
36 MetalForming/May 2023
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