Abstract:

In this paper,a new variable pivot structure of three-pad tilting pad sliding bearings is developed by replacing traditional tilting pad bearing mechanical pivots with fluid pivots.The forming principle of inner and outer layer films of the new fluid pivot bearing is described,and the initial work state of the bearing is analyzed.Then,the position of the bearing equilibrium under the initial work state is simulated,and the relationship between pad floating-required hydrostatic chamber area and static bearing load as well as rotor speed is expounded.In order to investigate the dynamic performance of the bearing and achieve test parameters,a test bench of journal bearing-rotor vibration characteristic is developed,which can perform automated data acquisition,real-time data analysis and other functions.Furthermore,both the double-sided balancing and the influence coefficient method are adopted to conduct a field rotor balancing test on the developed bench,and it is found that the proposed method in this paper is effective.Finally,the traditional journal bearing is compared with the variable pivot journal bearing in terms of rotor vibration characteristic and test bench machine feet acceleration vibration characteristic,finding that the developed bearing has a better damping characteristic.

Key words: variable pivot journal bearing, working mechanism, vibration characteristic, initial working state, experimental investigation