Spatial overall analysis of the electrostatic precipitator casing load bearing performance

The electrostatic precipitator used in the power plant is the important environmental protection facility to eliminate the flue gas. The casing is the most important technical component. The load bearing mechanism of casing is very complex. The overall load bearing performance of the casing structure is conducted by finite element method. The results of eigenvalue buckling analysis indicate that the first 60 buckling modes present the local buckling under the design load. It implies that the overall stiffness of casing is strong enough. Meanwhile, the column diaphragm, wall plate and top plate of casing are weak which are susceptible to local buckling. According to the construction and service process, in consideration of the influence of the loading path, the nonlinear analysis of the perfect casing structure is conducted by three load steps. The results indicate that the structural failure is mainly induced by the elasto-plastic local buckling of separating wide column and by the plasticity development on top beams. The eigenvalue buckling modes and the nonlinear buckling mode of perfect casing are introduced as the initial imperfection modes for the nonlinear analyses of imperfect casings. The results indicate that the casing is most sensitive to the initial imperfection mode that several local geometrical imperfections occurring on the diaphragm of middle separating wide column. All forms of imperfections occurring on the diaphragm of separating wide column or wide column reduce the ultimate bearing capacity of casing by more than 11%.