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Hydraulic pumps, cylinders, and other actuators deliver greater power in smaller packages than engines, electric motors, and mechanical actuators. Hydraulic valves easily control direction, speed, torque, and force with anything from simple manual operation to sophisticated electronic controls.
Yet, production methods that create these hydraulic components have not kept pace with the expanding scope of their applications. Enter metal 3D printing—it offers new opportunities to capitalize on the high power density of hydraulic technology by improving the design and production of components such as manifolds, valve blocks, and valve spools.
Three-dimensional printing, which began as rapid prototyping, has progressed beyond its original plastic materials to encompass many metal alloys. Although not practical or cost-effective for high-volume production, 3D printing offers many advantages when producing metal hydraulic components in smaller quantities and special designs.
Without the limitations of conventional machining, parts can be designed for the most efficient combination of production and performance. And internal channels can be optimized for higher flow and lower pressure drop. It’s also possible to produce several different prototypes within hours to determine the best design. Furthermore, components can be made from a variety of materials, including stainless steel (from AISI 304 to AISI 316L), aluminum, titanium, and new materials still under development. Sources of potential leakage from auxiliary drilling and subsequent plugging are eliminated.
Although hydraulic components can be produced either by traditional manufacturing or 3D printing, traditional manufacturing is a subtractive process that starts with a larger piece of material, usually a metal casting or bar. Material is removed, generally by CNC machining, to leave the desired shape. Excess material often is left in place to save the expense of removing it, resulting in parts that weigh more than necessary.
Machining also is limited in its ability to produce many desired configurations. Passageways in conventional manifolds often must be positioned to prevent cross-drilled channels from intersecting and allow enough material between channels to provide adequate strength. Auxiliary holes drilled to connect internal passageways may need to be plugged, creating the potential for a future leak.
Three-dimensional printing, by contrast, is a form of additive manufacturing, which builds up the desired part layer by layer. With 3D printing, flow channels can be placed exactly...
