All,
I ran into a problem this morning regarding Appendix EE and the note stating that this non-mandatory code section is only applicable when both of the below statements are true:
(a) There is positive pressure inside the shell or head.
(b) There is positive pressure inside the half-pipe jacket.
The situation is that my shell has a design pressure of atmospheric pressure @ 100°F and the jacket has a design pressure of 150 psig @ 100°F. My customer wants both sides to be U-stamped. I was operating under the assumption that the static head on the inside of the vessel would act as my "positive pressure" mentioned in (a) above. My AI is on the fence if EE is applicable in our situation; he is worried that my customer will drain the unit, but still has the half-pipe jacket pumped up, therefore making EE non-applicable again. But this seems true with any unit - if someone brings the pressure up on the jacket without pressurizing the shell/head, it is the same situation.
Has anyone run into this issue in the past? Is Appendix EE really not applicable when designing a half pipe jacket on an atmospheric vessel? If not, is there a way to still do a single fillet on the half-pipe jacket and keep it stamped to the ASME code? Because I cannot find a corner joint in UW-13 that would allow a single fillet per figure UW-13.2(p).
Thanks in advance for everyone's help.
Doug
I ran into a problem this morning regarding Appendix EE and the note stating that this non-mandatory code section is only applicable when both of the below statements are true:
(a) There is positive pressure inside the shell or head.
(b) There is positive pressure inside the half-pipe jacket.
The situation is that my shell has a design pressure of atmospheric pressure @ 100°F and the jacket has a design pressure of 150 psig @ 100°F. My customer wants both sides to be U-stamped. I was operating under the assumption that the static head on the inside of the vessel would act as my "positive pressure" mentioned in (a) above. My AI is on the fence if EE is applicable in our situation; he is worried that my customer will drain the unit, but still has the half-pipe jacket pumped up, therefore making EE non-applicable again. But this seems true with any unit - if someone brings the pressure up on the jacket without pressurizing the shell/head, it is the same situation.
Has anyone run into this issue in the past? Is Appendix EE really not applicable when designing a half pipe jacket on an atmospheric vessel? If not, is there a way to still do a single fillet on the half-pipe jacket and keep it stamped to the ASME code? Because I cannot find a corner joint in UW-13 that would allow a single fillet per figure UW-13.2(p).
Thanks in advance for everyone's help.
Doug
