
Corrugated expansion joint design, manufacturing, installation and operation management of multiple links consisting of reliability. Reliability should also be considered from several aspects. Selection of materials used in the selection of bellows in the heating network, in addition to the work, should consider the medium, working temperature and the external environment, we also take into account the possibility of stress corrosion, water treatment agents, cleaning of the pipeline affect the material, and on this basis, pointed out the material economy and the actual production of optimized bellows. Under normal conditions, the corrugated pipe material should meet the following conditions: 1 . High elasticity, tensile strength and fatigue strength to ensure that the bellows work. 2 . Good plasticity to facilitate the bellows forming process and to obtain sufficient hardness and strength by subsequent treatment process. 3 . Good corrosion resistance to meet the working of bellows in different environmental requirements.