Design for additive manufacturing and its effect on the performance characteristics of a control valve trim

Additive Manufacturing methods have been gaining popularity over the traditional manufacturing methods in the past three decades due to shorter product development cycles and reduced manufacturing costs. Selective Laser Melting is one of the most popular methods of Additive Manufacturing. In this paper, the effect of the manufacturing method on the performance characteristics of disc stack trims manufactured by Selective Laser Melting is investigated. Initially manufactured trim showed a reduction in the flow capacity as compared to the trim manufactured by Electron Discharge Machining. The reason for the reduction in flow capacity was found to be the increased surface roughness of the trim manufactured by Selective Laser Melting. Therefore, changes were made to the process parameters within the manufacturing method to improve the surface finish and its corresponding effect on the valve trim’s performance was assessed. Furthermore, a new design of the disc stack trim to aid the manufacturing method was also tested. The results showed that the changes to process parameters produced a negligible effect on the trim’s performance but changes to the design of the valve trim resulted in improvement of the performance. Results thus indicate that for critical applications it may be necessary to alter the design of the components to derive most benefits from additive manufacturing technology.