Development of Pressure Sensors Integration Method to Measure Oil Film Pressure for Hydrodynamic Linear Guides

The accuracy of the machined workpiece depends on the true conditions of the hydrodynamic linear guides. Linear guides based on hydrodynamic lubrication are still in use due to their high damping coefficient and high load carrying capacity. Measuring the true conditions of the hydrodynamic linear guide is important to achieve high accuracy. Until today, pressure measurement has not been established for linear guides. Oil film pressure is one of the important factors explaining the operating conditions of the hydrodynamic linear guides. The main goal of this study is to develop a method in which pressure sensors were installed in the lubrication gap to measure the oil film pressure under realistic condition of a hydrodynamic linear guide. A hydrodynamic linear guide testing rig with varying load capability was used as main test device. Multiple miniature pressure sensors were installed in a stationary rail in different manners to get the realistic oil film pressure distribution along the length of the slide. Additionally, the sensors were also calibrated hydrostatically and hydrodynamically with variable frequency and amplitude. Due to the problem of the enormous influence of air inside the lubrication gap of the testing rig, the measured pressure by the sensors showed that the numerical results have to be adapted to the experimental oil film pressure, which is lower. A new sensor’s integration method has shown great improvements in estimating the oil film pressure of hydrodynamic guides experimentally.