Nuclear piping components have been designed against plastic loads using the guidelines provided by section III, NB-3652 of Boiler & Pressure vessel code, ASME. For safe operation in the power plants, the structural integrity assurance of pipe bends is essential. The B2 stress index is used in the design equation for evaluating the primary stresses due to moment loading in the piping components. The code based B2 stress index is expressed in bend characteristic only. In real practice, consideration of bend angle, bend radius, nominal pipe thickness, and material properties of the pipe bends are needed. This paper presents a detailed investigation of the combined effects of variable wall thinning and ovality on B2 stress indices for pipe bends under closing moment using three dimensional finite element nonlinear analyses. Twice elastic slopemethodology (TES) was employed to get the collapsing moment from load deflection curve drawn for each model. From finite element analysis, it is observed that, the wall thinning produces a negligible effect on the B2 stress index, whereas the ovality produces significant effect.