by Eric Lanke
I got a good look at some possible additive manufacturing applications for fluid power on my recent tour of the Manufacturing Demonstration Facility (MDF) for additive manufacturing at the Oak Ridge National Laboratory in Tennessee. Our friends at the CCEFP helped arrange the tour on the tail end of the Fluid Power Innovation and Research Conference in October, and it was quite an eye-opening experience for me and the forty-some members of the fluid power industry that chose to participate.
In case you’re not familiar with the term, additive manufacturing is more commonly known as 3D printing—the process of “growing” a part from nothing, layer by layer, rather than starting with a hunk of metal and cutting or machining it down to the part you need. And ORNL has invested heavily in the technology, opening the MDF and making its resources available for a whole host of industries to experiment with, including fluid power. Dr. Lonnie Love runs the MDF, and he has a strong interest in fluid power, having served for the last nine years as one of CCEFP’s scientific advisors.
In the attached photo, we see one of Lonnie’s team members demonstrating the hydraulic-actuated robot arms that they recently printed, partly as an experiment and partly in an attempt to create a set of robotic arms to aid with undersea exploration and salvage operations. The first amazing thing about the arms is that they are made of titanium. That’s one of the new technologies that the MDF is quietly advancing—the ability to print in a variety of different metals—not just in the plastics and polymers that we traditionally associate with 3D printing. But things get more interesting when you look more closely at the arms. They are fully hydraulic, but there are no hoses or couplings. All the fluid pathways are internal to the structure—even through each of the joints—something that is just plain impossible to do with traditional manufacturing techniques. The valves that help control movement are also printed directly into the structure of each joint.
It’s a great example of what additive manufacturing makes possible for fluid power applications. Because of all this internal architecture—“grown” whole from the bottom up, rather than machined component by component then pieced together—the arms are extremely lightweight (they are, in fact, buoyant in the water they’re designed to work in) and, remarkably, they DO NOT LEAK. Since the fluid pathways are all enclosed in one continuous circuit, there’s no way for the hydraulic fluid to leak out. It completely changes the way one thinks about what’s possible with fluid power systems.
We’re currently looking for other ways to leverage this technology for fluid power applications. Through the CCEFP’s Industry Engagement Committee, we’re going to be sponsoring several fluid power-related projects with the MDF and sharing the results with our membership. If you’ve got ideas for how to apply additive manufacturing for fluid power, and would like to be part of the project team that connects with the MDF on these subjects, let me know. Focusing on new and emerging technologies like additive manufacturing, and deciding how our industry can best benefit from them, is a big part of NFPA’s core strategic priority of helping to foster an innovative environment for the fluid power industry.