Detection Method of Vertical Static Balance for the Marine Propellers Based on the Suspension Theory

To eliminate the static unbalance mass of the propeller through once grinding or counterweighing, the key problem is how to obtain solution of the static unbalance. Based on the suspension theory for the hydrostatic spherical bearing, a special detection device of vertical static balance for large marine propeller is researched and developed. The device can be used to detect the static unbalance mass. Moreover, two effective models based on the principle of moment balance are proposed. One is the offset model for the principal inertia axis, which can be used to calculate the mass and the location of the gravity center of the propeller. The other is the attached mass model, which is used to figure out the unbalance mass and the location of the unbalance mass for the propeller. According to the above two models and the static equilibrium condition for a rotor, the mass and location of the propeller, which need to be grinded or counterweighted, can be obtained. The purpose of this study is to provide an overview about specific algorithm for the static unbalance of propeller by addressing issues in recent patents and scholarly articles on such device.