Theoretical and Experimental Analysis of a Non Contacting Elastohydrodynamic Sealing

Authors

  • Matthias Scherrer Institute of Machine Design and Hydraulic Drives, Johannes Kepler University, Linz, Austria
  • Rudolf Scheidl Institute of Machine Design and Hydraulic Drives, Johannes Kepler University, Linz, Austria

DOI:

https://doi.org/10.13052/ijfp1439-9776.2421

Keywords:

elasto-hydrodynamics, non-touching seal, spool valve

Abstract

This paper presents a novel elastohydrodynamic sealing concept for the contactless sealing of spool valves. The basic goal is that the spool and the sleeve can be manufactured with standard mechanical engineering precision. High initial gaps are compensated for the elastic deformation of an elastomer seal driven by a self-regulating hydrodynamic effect. The final gap reveals a small leakage within the range normal for precisely manufactured spool valves and also features a low friction since a direct, solid contact between the seal and the sleeve is prevented. This sought-after behavior in ideal conditions is compared with imperfect situations by means of a simulation study and experiments. The simulation uses a Finite Element model which takes the seal‘s elastic deformation, the mechanical contact, the sealing gap pressure and the surface roughness into account. A simple prototype of the sealing system was produced to test its functionality in real conditions. Leakages of QLeak <= 18 ml/min @180 bar were recorded. However, an unexpectedly high friction occurred indicating an actual contact between the seal and the sleeve. The component roughness was identified as the cause of this behavior.

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Author Biographies

Matthias Scherrer, Institute of Machine Design and Hydraulic Drives, Johannes Kepler University, Linz, Austria

Matthias Scherrer was awarded his master’s degree in mechatronics from the Johannes Kepler University (JKU) Linz, Austria, in 2018. He is currently studying for his PhD at the Institute of Machine Design and Hydraulic Drives at the JKU and his research centres on simulations and the experimental study of hydraulic components and systems, especially exoskeleton actuations. He also has experience of working in industry in the field of hydraulics for Hainzl Industriesysteme.

Rudolf Scheidl, Institute of Machine Design and Hydraulic Drives, Johannes Kepler University, Linz, Austria

Rudolf Scheidl completed both his M.Sc. in mechanical engineering and PhD in engineering sciences at the Vienna University of Technology. He has experience in the research and development of agricultural machinery (Epple Buxbaum Werke), continuous casting technology (Voest-Alpine Industrieanlagenbau) and paper mills (Voith). Since 1990, he has been a full Professor of mechanical engineering at the Johannes Kepler University, Austria. His research focuses on hydraulic drive technology and mechatronic design.

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Published

2023-05-03

How to Cite

Scherrer, M. ., & Scheidl, R. . (2023). Theoretical and Experimental Analysis of a Non Contacting Elastohydrodynamic Sealing. International Journal of Fluid Power, 24(02), 141–170. https://doi.org/10.13052/ijfp1439-9776.2421

Issue

2023: Vol 24 Iss 2

Section

Original Article

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