Weld Designation 4

[dik]

I'm welding two same size W sections together, flange to flange, to double the depth of the beam. What is the designation of the weld at the junction of the two flanges? What is the symbol? and would the effective throat be noted as (1/4), in parenthesis? Thanks...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[KootK]

I'm not sure that there is such a weld unless you're willing to prep a groove weld which would get costly. Could you:

1) Use a WT to double up instead or;

2) Separate the two WF by intermittent, 1" thick plates and then just use fillet welds on those or;

3) A little weird but I suppose that one WF could be shifted an inch to the left of the other?

 

[phamENG]

I don't think there's a prequalifed weld for that scenario, dik. What about periodic holes in one flange with a fillet weld? Or grinding a bevel on one or both flanges, but again I don't know if you can call it prequalified.

 

[dik]

The client has a whole bunch of HP12x74s... and I need something stiffer for a heavy load spanning slightly over 20'... and was going to 'glue' two of them together... I'd normally spec a W24...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[Craig_H]

Having tried this in the past, with what sounds like a similar situation (beams sitting in someone's yard, they need something stronger than the existing sections), I can tell you that the mill tolerances will make fitting the two flanges nice and tight a very difficult task. Slight camber, skew, and twist will exist and make the fabrication of the combined beam a real challenge. Never mind that your shear flow at the neutral axis will be quite large, which makes this type of connection inefficient.

If there's lots of cheap material available, could the beams be used together non-compositely? Using two bearing plates positioned so that both the top and bottom beams are somewhat equally stressed is the solution that I went with in the past, and which I was able to make work. Of course, you might need to use more beams to make the strength and stiffness work...

 

[phamENG]

How about bolting it? If serviceability isn't a major concern, snug tight bolts may do the trick. If you really need to avoid slip, then it may be less cost effective.

 

[GastonLagaffe]

Any chance you can place them side by side and have cover plates on both side to join them? You can adjust the cover plate thickness as required to get enough stiffness / capacity. You also won't need to worry about LTB in that case. This'd let you save a good chunk on welding / prep / qualification.

I feel like anything with trying to weld the two beams one above each other will need some pretty significant welds since you're right at the neutral axis = max shear flow. I suspect that this cost will eat at any savings of using the HPs that way, unless they're doing it in-house and have the time.

 

[dik]

Thanks... I've convinced the client to run with the W24s... I knew there was a fit up problem and have used the 1/2" offset as Koot as noted... Problem is now moot. Thanks

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik