Metallic bellows are today used for a variety of application in wide range of fields from fusion reactors to simple vacuum components. These are mainly two types (1) welded bellows and (2) formed bellows, each of which are designed with different characteristics for different application. In this report the design of such bellows is described. In particular a new method of life-time calculation given by combination of examination and theoretical consideration will be explained. The usefulness of such calculations in terms of suitable bellows design and product standardization will also be outlined. New materials for the production increased life-time bellows will be looked at and finally we will show the application of metallic bellows in such areas as paticle-free gate valves for semiconductor production/processing equipment which require life-time >106 cycles, fusion reactors, particle accelerators and power electronic devices.
