VALVE MAGAZINE Spring 2024

3D PRINTED VALVE TRIM

strength and optimized flow area for improved performance over the previous solution. Using LPBF 3D printers from Nikon SLM Solutions, the company now 3D prints the Cavitrol Hex Trim in stainless steel and cobalt chrome at its facility in Singapore. In many cases, the trim can be 3D printed in just one piece, avoiding the brazing operations needed previously and resulting in a more reliable product. (Larger versions that exceed the build volume of the printers are printed in segments and joined.) Emerson is also realizing the benefits of flexible design through AM. Valve trim can be modified according to customer needs much more easily by simply modifying the digital file. The company says that more than 600 Cavitrol Hex Trim products have been sold thus far. Variable Resistance Trim Stack

Baker Hughes provides a product line of variable resistance trim stacks which conventionally have been produced by literally stacking together sheets of metal with holes drilled in strategic locations. Fluid is forced through a tortuous path inside the stack, again slowing its velocity and mitigating pressure drop that can otherwise lead to cavitation. While the variable resistance trim stack design is effec tive, manufacturing these devices in the variety of sizes and configurations needed has proven to be time-consuming and challenging. Producing these stacks conventionally involves machining each sheet individually, brazing them together and final machining operations on the assembly. The process required coordination with a series of vendors, frequently leading to long lead times and other challenges. “In each one of those manufacturing steps, you have a risk of something going wrong,” says Rebecca O’Donnell, senior product manager. “When you send parts out to third-party suppliers, even though they’re qualified, there’s still the risk of a quality issue that might occur. The purpose of doing the 3D printing is to make sure that we have total control of the part throughout. We monitor the quality and the lead times quite effectively.” To reduce the number of steps and vendors involved, Baker Hughes now manufactures its trim stacks with its in-house 3D printing capacity located in Houston, Texas. The stacks are produced on machines from Nikon SLM Solutions in Inconel 718, and have been made in a variety of sizes. The 3D printed anticavitation devices are very similar to the conventional design, with only minor adjustments to make the 3D printing and manufacturing process easier. By converting its trim stack designs for AM, Baker Hughes is realizing significant time savings as well

The 3D printed valve trim is available in new valves, and existing valves can be retrofitted with the new trim with minor modifications.

Cavitation occurs because of pressure drop which can be caused by a change in fluid velocity. The vena contracta is the point of minimal flow and maximum velocity, where cavitation is most likely to form. Source for photos and graphics this page: Emerson

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VALVE MAGAZINE

SPRING 2024