TEMA design has provision to check the actual longitudinal stresses in the shell and tube (periphery of bundle) against allowable stresses (both tensile and compressive).
The code provides a comprehensive guide to determine the allowable longitudinal compressive stress for tubes but mentions only briefly of allowable compressive stress for shell according to the Code (which in this instance, I presume refers to ASME V111.). I have following queries:
1.ASME V111 (UG 28) determines the allowale compressive vide computation of A factor and reference to charts in Appendix 5. Does ASME V111 allow provision to determine allowable compressive stress by calculation only ? I have seen some exchanger design by Japanese manufactureres using a formula for calculating the stress viz.
0.3Et/[D(1-0.004E/Y)] where E is shell elastic modulus, t is shell thickness, D is mean shell diameter and Y is the Yield stress for shell material.
2. It appears to me that the ASME determination of the allowable longitudinal compressive stress is higher than that determined per TEMA's formula? Why is that?
The code provides a comprehensive guide to determine the allowable longitudinal compressive stress for tubes but mentions only briefly of allowable compressive stress for shell according to the Code (which in this instance, I presume refers to ASME V111.). I have following queries:
1.ASME V111 (UG 28) determines the allowale compressive vide computation of A factor and reference to charts in Appendix 5. Does ASME V111 allow provision to determine allowable compressive stress by calculation only ? I have seen some exchanger design by Japanese manufactureres using a formula for calculating the stress viz.
0.3Et/[D(1-0.004E/Y)] where E is shell elastic modulus, t is shell thickness, D is mean shell diameter and Y is the Yield stress for shell material.
2. It appears to me that the ASME determination of the allowable longitudinal compressive stress is higher than that determined per TEMA's formula? Why is that?
