Bellows belong to a compensation element. Using its body of work stretching deformation effective bellows to absorb pipelines, conduits, containers, etc. by the thermal expansion and contraction and other reasons dimensional changes arising from, or compensate for pipelines, conduits, containers, etc. axial, lateral and angular displacement can also be used for noise damping. widely used in modern industry. bellows, customarily also called expansion joints, or expansion joints by its body of work constitutes a bellows (a kind elastic element) and the end of the tube, brackets, flanges, pipe and other annexes
Metal bellows comprises a plurality of link reliability design, manufacture, installation and operation management configuration. Reliability should also be considered from several aspects. Material selection of heating pipe network for bellows selection , should be considered in addition to the work of the media, outside temperature and the external environment, it should also consider the possibility of stress corrosion, water treatment agent, and pipe cleaning agents on the material, etc., combined with welded bellows material on this basis, molding and cost-effective material, preferably a bellows economical production of materials.
Under normal circumstances, the choice of bellows material should meet the following conditions:
(1) high elastic limit, tensile strength and fatigue strength, to ensure the normal operation of the bellows.
(2) good plasticity, easy bellows forming process, and can obtain sufficient hardness and strength through a subsequent treatment process (work hardening, heat treatment, etc.).
(3) good corrosion resistance, to meet the requirements of the bellows work in different environments.
(4) Good welding performance, to meet the bellows in the production process of the welding process requirements.
For trench laying of heat pipe network, when the low-lying compensation which the pipeline, rain or accidental water will soak bellows, should consider using a more corrosion resistant materials, such as iron-nickel alloy, high nickel alloys. Due to the high price of such materials in the manufacture of bellows, may be considered only in contact with corrosive media surface layer of corrosion resistant alloys increased fatigue life was designed by bellows compensator types and causes of failure can be seen, plane stability bellows circumferential stability and corrosion resistance are related to its fatigue life that is the amount of displacement. low fatigue life will lead to stability and corrosion of metal bellows Performance