The Lubrication Property Of Water Lubricated Rubber Bearing And Its Application

Water-lubricated rubber bearing is widely used in such drive systems as water turbine, water pump, propeller shafts and turbine drilling machine. Taking rear bearing of stern in propeller rotor system as object of study, the dissertation studies the lubricating property of water-lubricated rubber bearings with backing strips. Main researches and conclusions are made as follow:1. The force of rear bearing of stern and the distribution rule of stress-strain on each part are analyzed by adopting finite element method. The result indicates that the backing strip locating closer to propeller with more force on, its axial variation of stresses show more obvious; the distribution rule of major circumferential stress surface is similar to parabola; considering the actual structure of rubber strip, the researchers made further research on forces applied on rubbers surrounding screw hole under the effect of gravity and found out, the rubber area surrounding screw hole in contact with journal is larger than those connecting axle sleeve.2. The relationships among forces of bearing, eccentricity ratio, perigon, film thickness and rotate speed are analyzed theoretically without regard to elastic deformation of bearings. The analyzing result indicates that the pressure peak forcing on bearings increases with the eccentricity ratio. In different bearing clearances, friction changes gradually and gently when eccentricity ratio varies within a small extent; when eccentricity ratio increases larger than some certain numerical value and continues to grow, the friction will increase in rapid.3. Considering the elastic deformation of rubber bearing under the force of lubricated water film dynamic pressure, the dissertation analyzes, in the first place, the forces of rubber bearing without guiding gutter in operation condition, and then studies lubricating property of common concave surface V-type strip. The result indicates that in elastohydrodynamic lubrication analysis, the rotate speed and the stress forcing on rubbers are not just linearly correlated: the rotate speed plays a dominant role in affecting the stress forcing on rubbers; while the construction of bearings has less effect upon the stress, but it plays a pivotal role in dispersing stress distribution.4. The dissertation studies the lubricating property of bearings with different constructions, mainly discusses flow field distribution and the force of rubber strip. And thus makes a series conclusions including: with greater rotate speed comes more disorganized flow field and more balanced stress on rubber strip; trapezoid guiding gutter could facilitate dewatering, in equal eccentricity ratio and rotate speed, plane strip shows better bearing capacity than concave surface strip and convexity surface strip.