D/T>100

[adammilad]

Dear members,

I am working on a horizontal vessel currently that has an ID of 78" and a wall thickness of 0.375”. This is a Stainless Steel vessel therefore my goal is to keep costs as low as possible by limiting the shell thickness. I have designed the vessel in Compress and I have no deficiencies as it sits. My concern is that the D/t= 208. I have heard that there is an industry practice to keep vessels to D/t<100 due to shipping and possible deformation.

Do any of you feel that I would be wrong to leave my shell thickness at 0.375”? If any of you can shed some light as to where to get more information that would be great. I have checked in the Moss bock as well as the Pressure Vessel Design Handbook. I found some reference to D/L but nothing really for D/t.

 

[XL83NL]

No experience for me on this subject, but apart from the pressure retaining calculations done as per ASME you might need to take a look at this vessel as neing a beam too, and consider other failure modes (that typically may not applicable for smaller vessels), such as inward buckling due to external pressure or vacuum, circum instability, etc.
Im sure other members may provide better assistance than me but I think youll understand the problem.