HSS - End / Cap Plate Weld

[RFreund]

Is there a 'best' or most economical weld for a cap or end plate connection to an HSS member?
Assuming the cap plate will take load similar to this lifting lug problem:

http://www.eng-tips.com/viewthread.cfm?qid=256993

You could weld around the inside or outside using a groove weld or you could oversize the plate and provide a fillet weld. Is there one in particular that is better or ones that should be avoided?

I would preferably use the outside complete-joint penetration square (or V) groove weld with backing. Any issues with that?

Thanks

EIT

http://www.HowToEngineer.com

 

[TDIengineer]

If your tube thickness is less than or equal to 3/8", I would think an all around complete joint penetration butt weld would be the best. See joint designation B-L1a-GF for FCAW. Page 8-37 of AISC.

 

[Galambos]

TDI, i think your weld would require a backer bar which Im not sure would be very easily done. in my experience, the fabricator has to make a plate that matches the inside shape of the hss to form the backing.

The cjp welds will, if im not mistaken, require a backer bar (not easily accomplished) or backgouging, which is not possible with a closed hss.

So with that, a pjp weld is probably a better way to go.

BUT, for 1/4" hss member thicknesses, it usually leaves you with an 1/8" maximum effective throat. see pg 8-55 for geometric limitations of the PJP BTC-P4.

If you can get away with it, a fillet weld will require no preparation that is usually required for CJP and PJP welds and will be the easiest solution.

 

[connectegr]

100% oversize the plate dimensions and fillet weld. For thin wall thickness a fillet weld can provide the capacity of the HSS wall.

http://www.FerrellEngineering.com

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