| With the outstanding features such as in lowering friction and improving stability, hydrostatic/hydrodynamic bearings have been attached more importance in the field of super high speed machines. But the present hydrostatic and hydrodynamic bearings have the identical oil supply structure through the interior and exterior film, causing the difficulty in starting the floating ring and controlling the stability of the bearing-rotor system automatically through oil supply pressure as well. There remain many problems with this way of oil supply in journal-thrust floating ring hybrid bearings. For example, it is hard to choose the thrust oil film and the inner oil film restrictor; and it is extremely difficult to decide the boundary conditions and the coordinating conditions in computation. In order for such drawbacks in oil supply to be overcome, this paper presents a journal-thrust floating ring hybrid bearing structure in which oil can be supplied through the inner film and the outer film independently and lists the concrete design parameters, the processing methods and the processing technique. And in the meantime, such problems are solved as bearing end oil supply in processing the small deep hole in the inner film oil supply structure and the sealing of pressure measurement. On the basis of design, manufacturing the experimental bearing and test rig, through three times excitation method, the static and dynamic features of the floating ring bearing have been measured, and the factors resulting in trial errors are analyzed in detail and measures to eliminate the errors are introduced. Through contrasting the process of experiment data and the result of theoretical computation, a few important conclusions have been reached.This journal-thrust floating ring hybrid bearing structure ensures the smooth start of the floating ring, thus avoiding the probability for it to stick to the axle neck and the axle bush resulting from the external changes while the dynamic pressure floating ring is at work. What's more important is that the pressure of oil supply can be adjusted through automatic control of the inner and the outer oil film. In this case, once there appears film whirl or film whip in the bearing-rotor system, oil supply pressure can be reduced to control the film whirl or film whip.This paper also gives an overall analysis of the experiment apparatus, oil supply system and the problems and methods in loading system design and installation concerning the test of the static and the dynamic features in the journal-thrust floating ring hybrid bearing.This paper is one section of 2005 Natural Sciences Foundation Project of China (The characteristics and active control research of three dimension floating ring hybrid bearing-rotor system). (No. 50575212)... |
