Allowable Stress on Lifting Lugs

[Gordo2020]

I am conducting an FEA of a lifting lug on a Div 1 vessel. I am looking at the stresses caused by altering the lift angle from 0 degrees (vertical) to 45 degrees off the vertical.

The lugs are attached on the 2:1 elliptical head with a repad.

Am I correct in applying UG-23 (d) Sps = 3S as the allowable stress at the weld locations (Lug-to-repad) and (repad-to-shell)?

Thanks

 

[TGS4]

If you're doing an FEA, you'll need to refer to ASME Section VIII, Division 2. If you're using the 2006 (or earlier) edition, then you'll need Appendix 4. If you're using the 2007 edition, then you'll have to refer to Part 5.

There's a lot more to it than just comparing a peak stress from an FEA to an allowable...

 

[jte]

Don't forget that a secondary stress is a self-relieving type of stress. Like a thermal expansion stress for which, when a bit of deflection occurs the force / stress is reduced. To use 3Sps as a limit for stresses in lifting lugs is to argue that the load in the lugs is secondary. It is - but only after the vessel has torn off of the lugs thereby relieving the load.

jt