MSL68
Nuclear
- Jun 23, 2023
- 1
According to the stress classification table in ASME Sec. III Appendix XIII, the membrane stress due to internal pressure at any location in a cylindrical shell is classified as Pm. It also states that gross discontinuities are not considered for this categorization.
Intuitively, one would think that the membrane stress near an opening in the shell, say for a nozzle, would result in PL since there is a gross discontinuity present. But nothing specific is stated in the table for this situation and the considered discontinuity does not match for a location of the shell near an opening.
Does anyone have some insight on this matter? Obviously it would be conservative to assume it to be Pm, but just based on the geometry, you'd think it'd be classified as PL.
Intuitively, one would think that the membrane stress near an opening in the shell, say for a nozzle, would result in PL since there is a gross discontinuity present. But nothing specific is stated in the table for this situation and the considered discontinuity does not match for a location of the shell near an opening.
Does anyone have some insight on this matter? Obviously it would be conservative to assume it to be Pm, but just based on the geometry, you'd think it'd be classified as PL.