A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed.Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state,residual stress,bending stress produced by both itself weight and wind loads,it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress.After comparing four kinds of stress controlling conditions,the relation to stress with depth of angular distortion,grade of curvature of angular distortion and half of region of angular distortion has been inferred.Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted.The five steps for its engineering use have been explained.The lighter the grade of curvature is,the larger of bulge allowance,may be,and the bigger of depth of angular distortion may pose too.For the coke tower with a popular structure of Dg 5 400 mm×28 mm,the result by graph is nearly more than the result of two formulas formed by other research,the error is less than 7.0%.But,the graph can be easily applied to different size of angular distortion. A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed.Through stresses analysis of circumferential weld of coke tower and comparing the stressed produced pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have had explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth o For the coke tower with a popular structure of Dg 5 400 mm × 28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be applied applied to different size of angular distortion.