The design basis of metal bellows
The theoretical basis of metal bellows design is plate and shell theory, material mechanics and calculation mathematics. There are many parameters in the design of bellows. Due to the different USES of bellows in the system, the emphasis of design and calculation is not the same.
Requirements for several types of bellows:
1、For force balance element, the effective area of bellows should remain unchanged or change little within the working range.
2、For measuring elements, the elastic characteristics of bellows are required to be linear.
3、Used for vacuum sealing of vacuum switch tube, which requires vacuum sealing, axial displacement and fatigue life of bellows.
4、used for valves as seals, bellows should have a certain pressure resistance, corrosion resistance, temperature resistance, working displacement and fatigue life.
According to the structural characteristics of bellows, bellows can be used as toroidal shells, flat conical shells or toroidal plates. The design and calculation of bellows is the design and calculation of circular shell, flat cone shell or ring plate. The calculated parameters are stiffness, stress, effective area, instability, allowable displacement, pressure resistance and service life.