Metalworking fluids form a small but vital part of the overall lubricants industry. They boast good lubricity, cooling, detergency and emulsion stability, and remain an essential part in the manufacturing process, helping to reduce heat and friction when cutting, milling, rolling or forming. The fluids help provide the required cooling and lubrication for countless industrial applications, ensuring machinery operates as efficiently and effectively as possible.

A study from research firm Global Market Insights shows the sector was valued at $10 billion in 2017, with an expected 4.5 percent compound annual growth rate from 2018 to 2025.

Due to their unique mix of performance properties, including lubrication, cooling and protection, MWFs are indispensable tools in the metalworking process, said Sharbel Luzuriaga, project manager, Energy Practice at consultancy Kline & Co.

It is a challenging market but still offers plenty of opportunity. In developed markets there are opportunities for specialized, innovative and customized solutions, compliant to all the [health, safety and environmental] legislation, as opposed to emerging economies where an organic growth across all the segments and formulations can be expected, in line with their rapid industrialization.

Advances in MWF over the years have helped end users increase machining efficiency, improve surface finish and extend the life of their metals and tooling.

Various types of metalworking fluid are available, and each has a specific function. Removal fluids help to cool the material and tools during the cutting process-both of which are subjected to extremely high temperatures and pressures. Forming fluids, meanwhile, are used when bending or shaping material and offer protection from the heat. Protecting fluids help prevent oxidation, whereas treating fluids can help change the physical characteristics of a metal, often cooling the material to provide additional toughness and strength.

While the speed, precision and other requirements of manufacturing have evolved, the need for metalworking fluids remains critical, said Jon Plawchan, director, global strategic metalworking portfolio, Quaker Houghton.

As a supplier, we know it is the end users that will drive which trends are realized. Integrated solutions that cross applications, as well as deliver on the environmental, manufacturing, engineering, purchasing and safety requirements, will all factor into the process and techniques used, he said.

MARKET DRIVERS

There are two major macro trends shaping MWFs globally, adds Klines Luzuriaga. First, increasing uncertainty about the global economy and concerns of a looming recession could have a direct impact on trade and the manufacturing sector. He notes, too, that the MWF market may feel the effect of escalating United States-China trade tensions. On the regulatory side, climate change is prompting governments to focus more on sustainability and the environment, as well as implementing more stringent health and safety rules.

Other key market drivers are e-mobility and 3D printing, which some speculate may also impact future MWF use.

The surge of interest in the electric car and gradual move away from the conventional combustion engine means fewer metals will be needed under the hood. For now, however, with the electric vehicle market still in its relative infancy and countless metal components still required in cars, this is unlikely to dampen MWF demand too significantly.

Similarly, 3D printing is developing rapidly and is viewed as a potential threat to MWF in the longer term. This innovative technique allows often complex designs to be created using 3D modeling and advanced printers that systematically build up layers of material to create an object. Although highly effective when producing smaller, intricate parts, it is not really viable when needing to mass-produce large components cheaply and quickly.

Among other developments that may have an effect on future MWF demand are new machining technologies and processes, such as dry machining and minimum-quantity lubrication. Both are becoming more commonplace and remove or reduce the need for cutting fluids.

New materials may also have a bearing, noted Quaker Houghtons Plawchan. There is a much stronger focus on light-weighting today, and this naturally drives more attention to aluminums, as well as emerging materials-superalloys into automotive, carbon fiber into aerospace, sinter or powdered metals into both, high strength steels, bi-metals, he said.

RULES AND REGULATIONS

Health and safety is paramount when working with metalworking fluids, given the potential for skin irritation, respiratory issues or illness. Greater understanding of these risks over the years has prompted numerous regulations, restrictions and bans to be introduced.

For example, biocides are commonly used in metalworking fluids to control microbial contamination and have been subject to much scrutiny over the years, said Fred Passman, president of Biodeterioration Control Associates, Inc.

These additives, also known as antimicrobial pesticides, biocidal substances or microbicides, have proven extremely effective at prolonging fluid performance life.

However, due to regulatory pressure, the number of products available in Europe has fallen from over 200 just 15 years ago to 27 today. Similarly, in the U.S., there are now fewer than 50 different types of active substances, down from 180 over that same period.

Passman pointed out that despite the various concerns, there have actually been very few incidents of people suffering adverse health effects when biocides were used in MWF systems. Indeed, he suggests that there are greater risks associated with eliminating them.

Although they have been used in metalworking fluids for over a century, it was the increased uptake of water-miscible MWF from the mid-1950s that saw biocides become more prevalent, he said.

There were not only concerns that microbes may create a health risk in the work environment but that they could affect the stability of the fluid and cause it to fail, said Passman. Quite often users were changing the fluids at 8- to 12-week intervals. Some compounders later realized that microbicides and effective fluid management could help eliminate the need for repeated system draining and changeouts.

It was at that time that the regulatory agencies also determined that used metalworking fluids should be classed as hazardous waste, so the economics of preserving MWF changed significantly, he added.

As the years passed, more stringent regulations have resulted in fewer biocides being produced, partly because of the cost implications, as well as the onerous task of getting the products tested and approved.

New technologies are emerging, requirements are changing and regulation is tightening, yet despite this ever-changing marketplace, metalworking fluids continue to play an essential role. There are plenty of new opportunities, and the consensus appears to be that MWF will remain an important segment for years to come.