Control concept for a grease lubricated hydrostatic bearing

Abstract

In industrial practice greases are mainly used as lubricants in hydrodynamic plain bearings and roller bearings.The use in hydrostatic bearings is avoided due to the difficult controllability.One reason is the complex non-Newtonian flow behavior of greases.The motivation for this paper is the use of greases to increase the efficiency of hydrostatic bearings.The assumption is that the so-called yield stress of consistent greases can lead to self-sealing behavior in the bearing under stationary operation conditions.Assuming a volume-flow-free operation of the bearing, a concept for the active control of the sealing gap height and thus the bearing stiffness was developed.The concept idea is the use of a second medium with Newtonian characteristic for pressure transfer.The grease and the pressure control fluid are structurally separated.The grease is induced in the shortest possible way into the bearing pocket to keep the pressure losses as low as possible.The results of test bench investigations indicate the feasibility of a gap height control with very high bearing stiffness under use of highly consistent greases and initiate further investigation on non-stationary operation.

Authors 3

1. Igor Mass corresponding

   Hochschule Niederrhein

   Affiliation as printed

   Hochschule Niederrhein, Faculty of Mechanical and Process Engineering, Germany

2. Andreas Hoppermann

   Hochschule Niederrhein

   Affiliation as printed

   Hochschule Niederrhein, Faculty of Mechanical and Process Engineering, Germany

3. Hubertus Murrenhoff Aachen Institute for Fluid Power Drives and Systems

   RWTH Aachen University · Hochschule Niederrhein

   Affiliation as printed

   Hochschule Niederrhein, Faculty of Mechanical and Process Engineering, Germany

   RWTH Aachen University, Institute for Fluid Power Drives and Systems (IFAS), Aachen, Germany