Performance Assessment of Hydraulic Micro Relief Valve

Directly operated relief valves often exhibit abnormal or unstable behavior resulting in noise, premature wear, degraded performance, and failure. In this work, an investigation is carried out to assess the role of the hydraulic damper on the poppet element. The article reports the details of the investigation approach, integrating specific experimental tests with lumped-parameter modelling.Starting from a reference layout, the hydraulic behavior of different damper configurations is characterized (ranging from undamped to strongly damped poppets), for pressure and flow-rate conditions typically encountered in micro-hydraulic power packs. Depending on the damper design, the poppet operation ranges from unacceptability (due to noise) to fine-tuned response. The investigation give the chance to highlight how the damper layout impacts on the valve behaviour, in terms of pressure overshoot and settling time and provides the necessary information for relief valve design, modelling and analysis.