Non-circular Pressure Vessel - Partition Plate - Full Penetration weld size 1

[NimChimpsky]

Hi everyone,

I need some help locating the relevant weld size for a full-penetration weld on a partition plate (stay) for a non-circular pressure vessel (Air cooled Heat exchanger header box). I assume it should be minimum weld size (Throat) to be < Min plate thickness, however I need a reference or calculation proving this statement. E.g I have used ASME VIII UW-16 to validate the nozzle connections.


My first approach was to calculate the membrane stress on the stay via ASME VIII, Appendix 13-9-(3).

Then use the information posted in previous eng-tip posts referencing:

http://www.roymech.co.uk/Useful_Tables/Tribology/co_of_frict.htm

To calculate the stress in the weld.

*However as the partition plates are exposed to internal pressure on both sides of the vessel, the net pressure acting on the plate will be zero. *

Ensure the stress load on the weld is in accordance with ASME VIII, UW-18(a) and UW-15(c) and prove that the weld size is correct.

Although this calculation will not give me the minimum weld size explicitly it will verify that the weld is adequate. Has anyone had any experience of, or know exactly, the size of the weld?

Many Thanks for all your help,

 

[Duwe6]

You are over-thinking this: A Full-penn weld is the full thickness of that member. Period. If the member calc's good, so does the weld.

The calculations are for using partial-penn or filet welds instead of full-penn. In these cases, the weld could have enough less strength than the member to fail the calc. So you specify a bigger partial-penn weld; or just use a full-penn one.

 

[NimChimpsky]

Thanks for your post Duwe6.

 

[NimChimpsky]

Duwe6 perhaps you can help me further - If the joint was partial penetration only, would it still come under UW-13.2(e)?