The sub-plate and insulation support ring were adopted in the design of pressure swing absorber,which resulted in severe stress concentration in the local structures. And the fatigue performance became worse. Finite element analysis was used to analyze this problem. The results show that the fatigue life is less than 16. 8 and 3. 07 percentage of the design life,which is far from the design requirements of pressure swing absorber. The previous structure design is not reasonable. Then,it is redesigned that the upper part of the ladder is fixed in the operating platform,the lower part of the ladder is fixed on the skirt or foundation,and the support ring is designed into suspender structure. The new structure can avoid the weldments between the accessories and the cylinder of pressure swing absorber. It can also prevent the fatigue crack initiation and meet the design requirements of pressure swing absorber.