Flare Bevel root gap measurement?

By SWN1158 (***)

Date 01-07-2019 11:59

If AWS D1.1 is envoked, this joint (BTC-P10 and P10-GF) is not prequalified unless it's welded flush.

By 803056

Date 01-09-2019 01:53

Sorry to say I'm traveling for the next two weeks and I don't have D1.1 with me. However, I don't agree with the statement that the flare bevel must be filled flush to be considered "prequalified". I believe the weld size when the flare bevel or flare V is filled flush is simply the maximum weld size that can be used to calculate the capacity of the connection.

It makes little sense to insist the flare groove be filled flush if the design loads do not require a full size weld. To needlessly fill the groove flush only increases the resulting distortion.

However, without the code in front of me, it is difficult to take a defensible position on the subject. Having said that, if I recollect, the maximum weld sized based listed by the table in clause 2 id the same as the size indicated by the figure in clause 3. Thus, it supports my position the weld size list by the figure in clause 3 is the maximum weld size the designer can take credit for in calculating the capacity of such a connection.

Best regards - Al

By SWN1158 (***)

Date 01-09-2019 12:41

Al,

There's a note (L) in the prequalified joint criteria for BTC-P10 that states "weld size (E) shall be based on joints being welded flush."

Am I misinterpreting this note? I agree that the design loads can sometimes require less than flush, and when that's the case, the weld size that's needed is typically shown on the design drawings. In my experience, if a weld size is not shown in parenthesis, we weld the joint flush.

We recently had a job where the weld size was shown,and we welded them accordingly. The third party inspector rejected them because they were not welded flush and he submitted a report to the EOR, who approved them as is.

By jwright650 (*****)

Date 01-09-2019 15:22

"if a weld size is not shown in parenthesis"-Scott

Scott, I agree with you if the weld symbol does not have any weld size shown...weld it out flush.

By SWN1158 (***)

Date 01-09-2019 16:15

Ok John. Thank you! Typically a tube radius is 2x the thickness, and many times it ends up being a multi pass weld to fill it flush, which seems a bit much, and I've found that the estimators don't have enough labor to weld it.

By Jim Hughes (***)

Date 01-07-2019 12:26

Is this a bridge connection per AWS D1.5?

By pyramidappr Date 01-07-2019 20:39

This is actually an ASME III structural weld, but ASME doesn't give any direction on how to measure that configuration. Since AWS deals a lot with structural components, I was hoping it might be addressed in there code.

By Jim Hughes (***)

Date 01-08-2019 15:02

So this is a Nuke application?

By TimGary (****)

Date 01-09-2019 18:47

As far as HSS flare groove root opening is concerned, I would think that you would need to measure the distance between the faying surfaces of the tubes, or sidewalls, at or just below the radius line of the larger radius, though I can't supply a code spec or diagram to confirm.
AWS requirements for flare groove joints are vague, and leave too much open for interpretation, IMHO, which causes me a lot of grief.
As far as whether the weld has to be flush on the surface or not, I think the only way to accurately define that requirement is for a flush contour symbol included with the weld symbol, or a below flush detail included in the tail of a welding symbol or a drawing note. The purpose would be to head off possible differences in opinion during visual inspection.
Here's a link to a past discussion on this:

https://app.aws.org/forum/topic_show.pl?pid=280695;hl=flare%20bevel

Tim

By 803056

Date 01-09-2019 22:47

Thanks for the link Tim. It saves me from having to locate those sketches.

I agree, a flare bevel or groove symbol without a weld size enclosed by brackets indicate the weld is filled flush. If the detailer is savvy enough to include a weld size, the groove does not need to be filled flush. Whether the flare groove is filled flush or not, the flare groove is prequalified, but the designer cannot take credit for a weld that is larger than what is permitted by the figures included in clause 3.

By SWN1158 (***)

Date 01-10-2019 11:52 Edited 01-10-2019 12:03

Thank you Al. What I'm not understanding is the reference to the note that says "weld size (E) shall be based on joint being welded flush." What's your take on this?

By 803056

Date 01-10-2019 22:42

Glad to help when I can.

Al

By 803056

Date 01-10-2019 23:03

The size listed by the figure is based on the groove being filled flush. Again, I don't have D1.1 with me, but if I recollect, the weld size listed by the table in Clause 2 is the same as the weld size included in the figure found in Clause 3. Both indicate the largest weld size the designed can take credit for is the size indicated.

That doesn't mean the designer has to call for the largest weld size if it isn't needed to transfer the design load. It is no different that the case of a lap joint. If the members of the lap joint are 3/8 inch thick, the largest weld size permitted for the purpose of design is 1/16 inch less than the thickness. In this case, the largest weld the designer can specify is 5/16 inch. However, if the design load only requires a 3/16 inch fillet weld, the designer only has to specify the 3/16 inch fillet. He is not required to use the maximum weld size (5/16 inch) if it is not needed. The other provision that applies would be the minimum weld size based on the thickness of the base metal. If the base metal was 1 inch thick and the minimum fillet size permitted (based on the thickness) was 1/4 inch, the designer would be obligated to specify a 1/4 inch fillet even if 3/16 inch was adequate based on design load.

Best regards - Al

By SWN1158 (***)

Date 01-11-2019 12:01

Ok. Got it. Thank you so much!