Lifting using Shell Flange Lug (Dennis Moss)
Lifting using Shell Flange Lug (Dennis Moss)
(OP)
One of the lift options in the Pressure Vessel Design Manual 3rd edition by Dennis Moss is the Shell Flange Lug shown on pages 391 and 397. Has anybody used a shell flange lug in lifting a vertical vessel? How is it possible to lift a vessel in the vertical position?





RE: Lifting using Shell Flange Lug (Dennis Moss)
I'm actually working on a vessel right now that will use a top flange lug. This works for vertical vessels because the whole vessel hangs off the top flange. If you keep going to page 422, it discusses the design a little further.
For vertical vessels, I think the shell flange lug is more suited to be used to replace a tailing lug. The only way I could see using shell flanges to erect a vertical vessel otherwise is if you had two opposing flanges and essentially used them like trunions. This design would be different however from a standard Moss shell flange lug.
Cheers,
RE: Lifting using Shell Flange Lug (Dennis Moss)
RE: Lifting using Shell Flange Lug (Dennis Moss)
Yes, extra analysis is certainly required, but in some cases it is justified. Depending on the size of the vessel and location and orientation of nozzles, the use of lifting blinds can be a simple and smart solution.
In our case, due to fatigue cycling, the client would prefer to keep the number of attachments to a minimum. So trunions or lifting lugs are not preferred. We also have the benefit of a heavy forged manway on the top head that provides more than adequate strength. Add to that, we are building multiple vessels of the same geometry, and a single lifting blind can be used for multiple lifts.
RE: Lifting using Shell Flange Lug (Dennis Moss)