This stress occurs along the longitudinal axis of the bellows due to internal pressure. It acts on the sidewalls of the convolutions and must be controlled to prevent structural deformation. 3. Meridional Bending Stress
Founded in 1955, the Expansion Joint Manufacturers Association (EJMA) compiled decades of empirical testing and engineering principles into a unified structural standard. Document Scope & Purpose ejma standardpdf
Because bellows undergo cyclic movements, they are highly susceptible to metal fatigue. EJMA provides empirical fatigue curves based on decades of destructive testing. By calculating the total equivalent axial movement per convolution, engineers can use the EJMA formulas to predict the exact number of cycles a bellows can withstand before cracking. 3. Stability and Squirm Calculation This stress occurs along the longitudinal axis of
: To assist engineers and designers in specifying and installing expansion joints effectively. Design Scope Meridional Bending Stress Founded in 1955, the Expansion
Key design factors used in EJMA calculations include:
Ensure the specified joint can handle the combined effects of temperature, pressure, and cyclic displacement.