Precautions Of Expansion Bellows

A) The stability of the bellows, when both ends of corrugated pipe is limited, if the pressure inside the bellows to a critical value, the phenomenon of instability arises .
B) For working in the compressed status , its maximum compression displacement is: the bellows were crushed or squeezed to contact lead to maxdisplacement, also known as the structure allows maximum displacement, it is equal to difference of spread length and the length of maximum compression .
C) Bellows does not produce plastic deformation under the maximum displacement can be called allowed the bellows displacement.
D) Bellows in the actual work process will produce residual deflections and permanent deformation or plastic deformation, also known as deformation, bellows or deformation under pressure, when the force or pressure removed, the corrugated pipe does not restore the original shape of the phenomenon known residual deformation, the residual deformation is usually not restore the original position of bellows to represent the known amount of zero offset .
E) Bellows displacement and the relationship between the zero offset, either tensile or compressive displacement, the displacement in the initial stages of bellows, the residual deformation is very small, generally less than the prescribed standard bellows allow zero bit offset value. However, when the tension (or compression) increases displacement to more than a certain value, the zero offset value will cause a sudden increase, which means that relatively large bellows produce residual deformation after. If we increase the bit displacement, the residual deformation will increase significantly. So, not exceeding the bellows displacement, or will seriously reduce the accuracy, stability and reliability and service life
F) Bellows in the compressed mode of operation are bigger than work under tensile stretching displacement , so design of expansion bellows to work under compressed ,Displacement under compression is 1.5 times of the situation under extension status with the same size .
G) Displacement of expansion bellows depend on the size,specification ,material of bellows. Under normal circumstances, displacement of expansion bellows have direct ratio with material yield strength , with elastic modulus, wall thickness is inversely proportional . Meanwhile, the relative bellows depth, thickness also take effect .