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Up Topic Welding Industry / ASME Codes / Fillet Weld Size on Socket weld B31.1
- - By swsweld (****) Date 11-03-2009 04:44
I had a TPI fail some welds the other day stating that they were undersize because they were not filled out to the hub edge of the socket fitting.

I was not there to challenge the call and our welder just added another layer. We were T&M so it didn't cost us money but it did not make us look good to the client.

Looking at Fig. 127.4.4(B) Min. Welding Dim Required for Socket Welding Components other than Flanges it states that the min weld is 1.09t and t=nominal pipe wall thickness. The pipe wall is only .154 so the additional .09% is still less than 3/16" and we absolutely had more than that.

Am I missing something? I have heard of the "fill it out to the hub" requirement but have never seen it.
Parent - - By scrappywelds (***) Date 11-03-2009 22:03 Edited 11-03-2009 22:07
a case on going up and beyond the code to ones opinion. I will say if the fillet weld gets to big than in some cases the might have to have post weld heat treating, so you have to watch those little socket welds. I do not know but I think the legs of the fillet weld must be equal though no matter how big or little the weld is. There is always the option of measuring the welds with a gage to know what size they are, I would say on a hard money job what the job specs call for is what they would get anything else no problem just pay the extra work order.
Parent - By MBSims (****) Date 11-04-2009 04:05
An equal leg fillet is not always used.  It is not uncommon in the power plants, mainly nuclear, to use a 2 x 1 fillet profile to reduce the chance of fatigue failure.  The leg on the socket is made to 1.09t or 1.4t, whichever is applicable, and the leg on the pipe is twice the size of the other leg.  This reduces the stress concentration at the toe of the fillet on the pipe.

Welding out to the top of the socket face is overkill and wasteful in most cases.  On the XXS or SCH 160 CrMo it can push you into a throat size that requires PWHT.
Parent - - By mightymoe (**) Date 11-03-2009 22:23
It looks better when it's filled to the edge of the socket.
On smaller size socket welds I usually have to weld to the edge of the socket to get desired fillet size.
I've noticed on some 2" and up, depending on the type of fitting, you can get a properly sized weld with out welding to the edge.
There is no rule in our shop " fill it out to the hub".  I ask our QC guy tomorrow.
Parent - - By 803056 (*****) Date 11-03-2009 23:27
Are you talking about an integrally reinforced branch fitting, i.e., a weld-o-let?

A similar question was asked under the thread of "weld-o-let". Jon responded with an offer to provide some details written by Walter Sperko. The requirements are clearly delineated by Walter in one of the best descriptions I've seen.

Best regards - Al
Parent - - By mightymoe (**) Date 11-03-2009 23:56
I think we're talking about regular old socket welds. Not sock-o-lets, weld-o-lets, or thread-o-lets.
Parent - By swsweld (****) Date 11-04-2009 04:26
That's correct. It was a socket weld 90 elbow.

I visited the site today and the mechanical QC and the supt. told me that the TPI was a complete jerk. Wanting to find problems that weren't there. He did not make a good impression and will not be called back. He had problems with unequal leg welds and excessive convexity. He said they were too humped up. The welder that made these was in a jack stand and though I didn't see these welds I have inspected many of his welds recently and he does very good work. Cosmetically, he is very good. There was no mention of porosity, undercut or other discontinuities that are obvious he just made opinions on things that nobody on site had the background to argue the acceptance criteria.
On paper he did not reject anything, that I am aware of. Just some grandstanding and requiring additional welds.

The site QC and the supt saw no problems at all with the welds (jack stand work) 

I don't think this guy cares about the "Inspectors Creed"
3) Have the attitude that you are trying to prove the work is done correctly, even when you find it is not.

He had the attitude that he was trying to prove the work was done incorrecty, even when it was done right.

It's not a big deal I was just wondering if I had missed something in 31.1 about the "fill out to the hub edge"

Parent - By CWI555 (*****) Date 11-04-2009 13:22
2007 31.1
127.4.4 Fillet Welds. In making fillet welds, the
weld metal shall be deposited in such a way as to secure
adequate penetration into the base metal at the root of
the weld.
Filletwelds may vary from convex to concave. The size
of a fillet weld is determined as shown in Fig. 127.4.4(A).
Typical minimum fillet weld details for slip-on flanges
and socket-welding components are shown in Figs.
127.4.4(B) and (C).

Fig. 127.4.4(B) Welding Details for Slip-On and Socket-Welding Flanges; Some Acceptable Types of Flange
Attachment Welds

tn = nominal pipe wall thickness
xmin. = 1.4tn or thickness of the hub, whichever is smaller."

If this is not a slip on flange, your TPI needs to learn how to read the code.
The thickness of hub requirements are limited to slip on flanges.
If this was a flange, then your TPI has answered justly.

Up Topic Welding Industry / ASME Codes / Fillet Weld Size on Socket weld B31.1

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