Study Of Spherical Friction Pair Based On Hydrostatic Bearing Of High Precision Static Balancing Machine For Huge Rotor

Static balancing machine for huge rotor based on large-scale spherical hydrostatic bearing has some virtues, such as high measuring precision and measuring convenience, so it will be replace traditional horizontal static balancing machine for huge rotor. Furthermore, the friction and flow characteristics of the spherical pair of hydrostatic bearing have important influences on the design and measuring accuracy of static balancing machine.So, combining the item of Marine Propeller Plant, hydraulic static balancing for huge propeller, study of spherical friction pair of static balancing machine for huge rotor was done in this dissertation. It will provide some theoretical foundations for the design of high precision static balancing machine for huge rotor and the practice of static balance detection.Firstly, the friction and static characteristics of large-scale spherical pair were studied. The suitable structure parameters of the spherical pair were chosen through analyses of load capacity, oil pressure, leakage rate and the processing of it. The calculation formula of static friction torque of spherical pair was set up. And the effects of capillary tube and structure parameters of spherical pair on the support property and oil film stiffness were investigated.Secondly, the squeezing effect of oil film under huge load of spherical pair was analyzed. The damping of squeezing effect was studied. And squeezing time was explored. The conclusions show that the damping and squeezing time are dramatically influenced by structural parameters of spherical pair.Thirdly, The working principle, structure and characteristics of static balancing machine for huge rotor were presented and the physical model of suspension system of it was established. Basing on it, the mathematics models of suspending system were derived. Two kinds of situations of the interior supporting collet of static balancing machine were considered for the elasticity deformation and no elasticity deformation. At the same time, linear simulation models were set up with Laplace transform. The digital simulation of thedynamic processes under step load input and supply oil pressure fluctuation were carried on by MATLAB. Analysis of the dynamic characteristics was done with the changes of the supply pressure, load, structural parameters of spherical hydrostatic bearing and the effective bulk modulus of oil. The conclusions show that structural parameters of the spherical bearing and the effect bulk modulus of oil have significant influence to dynamic characteristics, but the elasticity deformation of interior supporting collet has very small influences on the output response characteristics of the suspension system. The collet's deformation can be neglected on the project.Finally, the experimental equipment was set up applying similar principle, in order to carry on the study of friction mechanism of spherical pair of static balancing machine. The design of test system was finished, and the scheme to measure the static friction torque of the spherical pair was designed. At the same time, the methods for measuring the pressure oil recess, the leakage rate and the oil film thickness of the spherical pair were put forward.