Magnetorheological finishing of industrial ball valve curved surface for enhanced in-process sealing performance

Ball valves are widely utilized in various industries to regulate the flow of liquids or gases through pipelines and ensure leakage prevention. The durability and effectiveness of these valves primarily rely on the surface smoothness of the ball, which is essential for providing a secure shutoff seal. Achieving a uniform surface finish on the curved profile of a ball presents a significant challenge due to its continuous curvature. To address this challenge, a novel compact and adaptable improved magnetorheological finishing (MRF) tool was designed to operate efficiently with swirling motion. This innovative configuration enhances finishing performance on complex curved surfaces. Finite element analysis was employed to investigate the magnetic flux distribution within the improved MRF tool, which controls the stiffness of the magnetorheological polishing fluid and ensures precise finishing of the ball surface. The initial surface roughness parameters were measured as Ra = 0.60 μm, Rq = 0.75 μm, and Rz = 3 μm. After 90 minutes of the MRF process, these parameters were reduced to Ra = 0.059 μm, Rq = 0.08 μm, and Rz = 0.4 μm. The surface characteristics of the ball valve curved workpiece surface were analyzed before and after the MRF process. Also, the pressure-holding capacity of the finished ball valve curved workpiece surface was analyzed using the computational fluid dynamics. Improving surface quality and reducing surface roughness parameters, enhance performance, minimize friction, extend the lifespan of the workpiece, and help prevent leakage. This improvement in surface precision and smoothness of the ball improves the valve's ability to maintain a leak-proof seal and pressure-holding capability in various industrial applications.