This investigation focused on the analysis of the cracks in the expansion joints for a chemical plant. It was found that the cracks formed because the allowable displacement was insufficient to relieve the thermal stress originating from the heat exchanger. In this regard,a new⁃type expansion joint was designed providing a fast and effective approach to solve the problems concerning the leaking of flammable and explosive gas. Based on the successful operation within 12 years,this expansion joint of new type was verified to be secure,economical and practical. Furthermore,with an expansion range exceeding that of the standard ones with the same specification,it can be used to replace the expansion joint with single wave,and applied in structures where the compensation is moderate.