Flare bevel symbol

By 13Hertz Date 01-06-2016 03:51

I'm hoping to get help shedding some light on how to determine what to call out on those non textbook joint designs. I'm plenty familiar with the flare bevel when it's obvious (tube laying on plate, joint created by the radiused corner of square tube, etc) but when does the line get crossed when dealing with say a fin running down the center and parallel with the axis of a tube. For example, I would call a 0.25" plate on a 4" OD tube a fillet but what happens when the tube OD gets smaller or the plate gets thicker and the "groove" is more pronounced? Is it determined by how the weld would be measured? Thanks in advance.

By Lawrence (*****)

Date 01-06-2016 12:51

Welcome to the Forum 13Hz !

That's a really good question. It sounds like you are describing a skewed T joint.

But using words is always tricky,,,, But a detailer who actually is trying to get the weld symbol correct should be encouraged and helped eh?

Is this type of assembly that you are describing?

By js55

Date 01-06-2016 13:08

I think Lawrence has covered it well. It really depends on what it is you are trying to accomplish. Its not so much the joint configuration as it is the intended weld. If the intent is a fillet then it isn't a flare groove. In the cases as Lawrence demonstrated an obtuse angled skewed T is more accurate.

By welderbrent (*****)

Date 01-06-2016 16:04 Edited 01-06-2016 16:06

13Hz,

Welcome to the AWS Welding Forum!!

Now, if I understand both you and Lawrence correctly I think there are a couple of differences as I don't believe Lawrence's illustrations depict 'Skewed Joints' and definitely not fillets since they do not show the weld in the joint. A skewed joint would have the plate coming into the tube in such a manner that the welds would be of differing angles from the two sides, these are equal on each side of the plate to tube connection.

Having said that, I do think he has attempted to depict what you were asking. Please correct us if we have interpreted your query wrongly.

It will ultimately depend upon the total size of both the tube and the plate in order to know just how much of an opening there will actually be at the point where weld is to be deposited. It may also depend upon the welding process as even a small opening could be considered a flare bevel if using GTAW whereas it would take a somewhat larger opening to consider it anything other than a fillet weld if using FCAW with 1/16" electrode or SMAW with a 5/32 electrode.

Some of this could be an exercise in semantics but hopefully you can see what I am talking about and there can be differences in application which ultimately needs a lot more information and even pictures.

This issue can even be the case when dealing with tubing laying on it's side on a plate as you mentioned. If the tubing is square and not round you may still end up with a flare bevel if the tubing is large enough and especially as the wall thickness increases so that there is more of a corner radius. With say a 1" sq tube with thin wall it will be reasonably square and considered a T joint for a fillet weld especially for most welding processes but as the tube gets larger and thicker the radius increases to a point where it can easily be a flare bevel for some and is up for grabs unless one wants to get very picky and technical.

Rebar, round bars, tubing, all have applications of flare bevel welds and even when bringing the plate into a joint configuration as illustrated by Lawrence it can be difficult to define without much more information.

Now, to be more precise in answering your question, I don't believe the code really gets down to defining when a fillet weld becomes a flare bevel weld. But, I will have to do a little more research to see what I can find.

He Is In Control, Have a Great Day, Brent

By Lawrence (*****)

Date 01-06-2016 16:36

More to think about.

Most certainly skewed. What symbol is what we need to hash out :)

By 803056

Date 01-06-2016 18:31

Based on Lawrence's sketches, I would specify the welds as fillet welds, even in the case of the thick plate welded to the small diameter bar or tube. The reason is that the weld size of the flare bevel and the flare V groove is predicated by the diameter of the round member. I would venture to say that in most cases the weld size restriction of the flare groove would be less than the minimum weld size of the groove weld. The minimum groove weld size is a function of the thicker member or the load, whichever requires the larger weld size.

I would draw a sketch, but this new version of Acrobat (it sucks by the way) requires a monthly subscription (fee) to permit one to convert a drawing to PDF and then to JPEG.

Best regards - Al

By Kix

Date 01-07-2016 14:38

Al,

Say I'm the engineer for Lawrence's 3rd big sketch and I want you to penetrate half way into the plate material on each side of the plate, plus put a fillet weld on it. Would you still call it just a fillet weld or a single bevel with reinforcing fillet weld symbol or something else? :grin:

By Lawrence (*****)

Date 01-08-2016 19:43

Not totally related to the original post, but interesting nonetheless.

Here is some guidance from The Canadian standard CSA W59-13..... There are a lot of things I like about the CWB

4.3.1.6.2.2
Flare bevel groove welds in T-joints made on round bars or tubing having radii less than or equal to 10 mm
(3/8 in) or on square/rectangular HSS members (including 90° bends in formed sections) having measured
corner radii less than or equal to 10 mm (3/8 in) may be designed and detailed as fillet welds but referred
to as flare bevel fillet welds. The root of such a fillet weld is assumed to be the intersection of the planar
surface and a tangent to the curve of the flare that is perpendicular to the planar surface (see Figure 4.4).
For welds not designed as a fillet, the throat shall be established through qualification (see
Clause 4.3.1.6.2.8).

By 803056

Date 01-09-2016 22:18

I would expect to see a mock-up and a macro-etch to verify what you propose can be produced. If it can, I would use a welding symbol that combines the flare bevel and the reinforcing fillet weld.

Best regards - Al

By Kix

Date 01-19-2016 16:29

Even with the radius being that big it would still be considered a flare for the welding symbol? To Lawrences post, 3/8" and under get the designation as a flare per CWB, but in the case above and the radius being as big as it is, would a flare be appropriate? Doesn't sound like it is spoken to very well in AWS standards, so could it be correct either way?

By 803056

Date 01-20-2016 01:49

Personally, I like and I think it is best for was a couple of mock-ups to see what works and what doesn't work. The code cannot foresee every permutation possible. They do address 90% or more of the joints used by fabricators. Anything that isn't addressed by the code should be validated by testing. The responsibility for testing should be borne by the party that proposes the unproven joint detail.

It is easy enough to weld a couple of mock-ups, section them, perform a macro etch and verify the size of the resulting weld. Now, the Engineer and the contractor have something concrete they can use as a basis of making rational decisions.

Best regards - Al

By Kix

Date 01-21-2016 19:20

I agree with you 100% for testing odd ball joint configs. I'm just curious about weld symbol that would be used to call out such a joint. We're actually getting ready to quote a job that has a few odd ball full penetration box tube joints that will have to be production mock upped and tested. Should be interesting.