ASME Sec 8 Div 1 Threaded Endplate

[tc112]

I have included a screen capture of a threaded end cap for an ASME Sec 8 Div 1 pressure vessel that the company I work for has manufactured for a very long time. Recently we have been questioned on the wall thickness of the shell at the threads. I have looked at UG-31 but this seems to apply to shell wall thickness with exposed threads whereas our design has no exposed threads. I can't seem to find anything in the code that I can use to verify the reinforcement that the threaded nut adds to the wall thickness under the threaded portion of the vessel. Does anyone have experience with this or know of code/code case that would address this?

Thanks

 

[loilfan]

Good question - I haven't seen anything regarding this. Anyone else?

 

[SnTMan]

tc112, I doubt you are going to find anything explicit on your construction. It seems to me that UG-31(c)(2) would apply, threads exposed or not. You may perhaps consider reinforcement by the nut per U-2(g).

Regards,

Mike

 

[SPDL310]

Could you adapt something from section ULW to consider the nut as reinforcement at the threads?