The Tribological Property Design And Study Of High-Speed Railway Bridge Isolation Spherical Bearings

With the rapid development of high-speed railway technology in China and the improvement of bridge science,more and more people start to pay close attention to the isolation spherical bearing which is a small component but plays a pivotal role in the bridge structure.During working process,spherical bearings sliding plane often suffers from severe wear,and it reduces sliding planes,even spherical bearings,lifespan drastically.Accordingly,it is meaningful to innovate a special spherical bearings with low friction coefficient and great wear-resistence ability for improving spherical bearings lifespan.In this paper,it shows the structure design of the traditional bridge bearings,and the statics analysis and dynamics analysis which are finished by Solidworks and Workbench.It also includes a specific PTFE sample that is made of CF,CNTs,GO,which are used as addition phase,and original PTFE material that is used as matrix.The mechanical property and tribological property are discussed in this paper as well.Such PTFE plane sample of isolation spherical bearing is made through mixing,cold pressing,sintering and curing processing,and the mechanical property of new PTFE,like rigidity,tensile strength,compression strength,bending strength and impact toughness,has been improved clearly.In the friction-abrasion test,the static friction coefficient,stable friction coefficient,abrasion of sample and the impact from revolving speed and press to friction coefficient and abrasion are all observed,and the result shows that,the addition of CF and CNTs has magnificently decreased the abrasion of the testing sample,and the addition of GO has lowed the friction coefficient.And it also shows that,the increase of friction coefficient and the decrease of abrasion are all determined by both impact from addition of CF and CNTs and he addition of GO.The observation of micro structure abrasion shows that the main abrasion of original PTFE sample is composed of the effect of furrows and adhesive wear.The addition of CF and GO have changed the wear mode from he effect of furrows and adhesive wear to fatigue spalling and adhesive wear.The CNTs which are mixing with the matrix,play an important role in bearing the load and decreasing the wear.Instead of matrix,CF and CNTs become the part which would rub against the abrasive component,and it decreases the wear of matrix successfully.CF and CNTs also are essential parts of suppressing the creation and expanding of crack,due to the effect of bridge and pinning.This paper also formulates the mathematical model of PTFE sample with transfer film.According to the difference between abrasive component and sample's rigidity,the static friction coefficient,which is attributable to the effect of furrows,is indispensable to be considered so that the mathematical model of furrow friction coefficient.The final formulation of PTFE friction coefficient can be obtained from the addition result of these two mathematical models.Finally,this paper builds up the 3D model of isolation spherical bearings and designs an innovative wear-resisting slab with a new kind of texture.After finishing the statics analysis,modal analysis and dynamics analysis through Workbench,the analysis results demonstrate that the isolation spherical bearings showed in this paper is suitable to the designed standard,and also has ability to resist quake properly.