Pilot Pipe and Damping Orifice Arrangements Analysis of a Pilot-Control Globe Valve

Abstract

Compared to conventional globe valves, the pilot-control globe valve (PCGV) possesses advantages of lower energy consumption and higher space utilization. In order to analyze the effects of pilot pipe and damping orifice arrangements, this work proposes four PCGVs and conducts simulations to compare their overall performances, overall flow characteristics, and local flow characteristics around the valve core. In general, the arrangement of the pilot pipe has larger effects on the hydroperformances of PCGVs than the arrangement of the damping orifice. The pipe-parallel-mounted type PCGV performs better in hydroperformance than the pipe-perpendicular-mounted type PCGV, and thus is recommended in practice. As the specified valve core travel increases, the flow resistance of PCGVs decreases and the flow capacity of PCGVs increases. However, overlarge specified valve core travel has little effects on the flow resistance and flow capacity of PCGVs. Besides, the increased specified valve core travel could effectively reduce the wear induced by the uneven pressure distribution on the external lateral face of valve core, but it has little effect on the wear induced by the uneven pressure distribution on the bottom face. For all pipe-perpendicular-mounted type PCGVs, the variation of axial force imposed on the valve core relative to the specific valve core travel presents similar tendencies under different incoming flow velocity within the scope of the investigation, which could be concluded into a fitting equation. This work could be referred for the optimization of PCGVs and other similar valves.