The metallic expansion joints manufactured by FLEXILATINA COLOMBIA are calculated according to EJMA standards, ASME BPVC SECTION VIII AND/OR ASME B 31.3.
Each one of the metallic expansion joints manufactured is supported by its respective data sheet and the calculation of the bellows according to the respective code.
DN. Nominal diameter.
Db. Internal diameter of the bellows.
t. Bellows material thickness.
W. Wave height of the bellows.
q. Pitch between bellows waves.
Lt. Tangent length.
P. Design pressure.
T. Design temperature.
▲X. Axial movement (Extension or compression).
▲Y. Lateral movement.
▲ß. Angular motion.
Ebh. Modulus of elasticity of the bellows material at design T°.
Ebc. Modulus of elasticity of the bellows material at ambient T°.
Eq. Modulus of elasticity of the collar material (if used).
Sab. Allowable stresses of the bellows material.
Sac. Allowable stress of the collar material.
Sy. Elastic limit of the bellows material.
Stresses due to internal pressure.
S1. Stress in the circumferential tangent membrane.
S1′. Stress in the circumferential membrane of the collar.
S2. Stress in the circumferential membrane of the wave.
S2-E. Tension in the circumferential membrane of the final wave.
S2-I. Tension in the circumferential membrane of intermediate waves.
S3. Stress in the meridional membrane of the bellows.
S4 Stress due to meridional bending of the bellows.
Stresses due to deformation.
S5. Stress in the southern membrane of the bellows.
S6. Southern bellows bending stress.
Nc. Number of fatigue life cycles.
Psc. Internal pressure limit due to column instability.
Psi. Internal pressure limit due to plane instability.
Fiu. Theoretical axial constant of the bellows.
Frp. Reaction force due to internal pressure.
Fx. Axial force at the joint.
Fy. Lateral force on the joint.
My. Lateral moment on the joint.
Mß. Angular moment on the joint.