Research On A Water-lubricated Radial Journal Bearing Test-Bed

Radial journal bearings are key components in the pure water-lubricated hydraulic pump and motor. Its structures and performance parameters have substantial influence on the capability, reliability and service life of the hydraulic pump and motor. Based on the working environment and operating conditions of the hydraulic pump and motor, establishing and perfecting the design theory of the water-lubricated journal bearing is of great importance for the development of water hydraulic power transmission technology. As a result, the research on the water-lubricated radial journal bearing test-bed is becoming an urgent problem to be solved.A water-lubricated radial journal bearing test-bed is introduced in this paper. It is composed by a mechanical system, a hydraulic system and a signal testing system. The mechanical system consists of a housing block, a shaft, the journal bearing to be tested, a bearing bracket, a loading cylinder, etc. The hydraulic system can be divided into a lubrication system and a loading system, both of which are powered by the same water hydraulic pump. With corresponding adjustment of the hydraulic system, it can achieve either hydrodynamic or hydrostatic lubrication. The signal testing system is a data collecting and processing system based on the software LabVIEW. It can dynamically or statically real-time display the performance parameters of the journal bearing.In order to probe into the flow field of the water-lubricated radial journal bearing, based on the fundamental theories of the hydrostatic and hydrodynamic lubrication, this paper respectively researches on the flow field simulation of the hydrostatic and hydrodynamic journal bearing. The laws that load carrying capacity changes with eccentricity and supplying hydraulic pressure under hydrostatic condition have been obtained. The rules that water film pressure, water film rigidity, load carrying capacity, angle of displacement changes with eccentricity under hydrodynamic condition have also been acquired, which can provide theory referrence and support for the journal bearing test research.Experiments on the hydrostatic radial journal bearing are carried out on the test-bed. The rules that the friction torque, eccentricity, angle of displacement and water film change with time have been obtained, which can provide experimental reference for perfecting the radial journal bearing theory.