According to nonlinear relation of unbalanced magnetic pull with respect to rotor eccentricity,a nonlinear system represented by a symmetrical disk is set up to express electromagnetic vibrations of hydro-generator rotors,the steady-state responses of forced vibrations of the nonlinear system are analyzed theoretically by the method of multiple scales,thus the electromagnet.

The unbalanced magnetic pull(UMP) in a three-phase generator, caused by relative eccentricity, is calculated theoretically, and its effect on vibration of an eccentric rotor is studied.

A survey on the research of the unbalanced magnetic pull(UMP) in the motors is given in the paper.

Through combining the actual condition of the piping layout of offshore platform and calculating the unbalance force caused by pulse,it confirms the method is the best.

Unbalance forces of the engine is the main reason for vibration of motorcycles.

On unbalanced forces in 3D elasto-plastic FEM analysis;

Under the action of a given load the area where unbalanced force area existed is the location of initial failure occurred.

The main ingredient of the theory is that the unbalanced forces of a deformable body in elasto-plastic elaborated.

Based on the concept of constraint-equilibrium in non-equilibrium thermodynamics, deformation reinforcement theory,which analyzes the mechanical behaviors of unstable structure with unbalanced forces exceeding the yield surface,is presented.

It points out that under the given external loads,the area which comes to unbalanced forces is the first place to be destroyed in the structure.