Flange to Pipe fillet weld size Limitations

[PVG1]

First off I don't know if I should post here or on Pressure Vessel and Boiler forum, but anyways...

I have a 10" sch. 40 pipe and a slip-on flange for use in ASME Sect VIII, Div 1. The fillet weld on the outside of the pipe to flange is calc'ed at 9/16"...

Is there anything that limits the size of the fillet being greater than 1/2", some one at the shop mentioned they can't go above 1/2" and didnt give a reason, and usually the size is 3/8", but with this particular configuration we need a 9/16" fillet

 

[LittleInch]

If you need 9/16" then use 9/16". This sounds typically like someone has been told this a long time ago for a particular set of circumstance or has been told it as a default value in place of anything else, but doesn't know why and can't quote a code section or reason. Ignore them.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[PVG1]

OK thank you!

 

[gtaw]

There is a limit on depositing a single pass weld larger than 1/2 inch when welding groove welds. If one wishes to deposit groove welds with individual weld beads larger than 1/2 inch, it must be qualified by testing.

If the weld is deposited as a multipass weld, the 1/2 inch limitation does not apply as long as each weld bead is less than 1/2 inch thick.

Best regards - Al

 

[PVG1]

gtaw:

That is the only thing I saw too, with our weld procedures, 1/2" max weld pass, the 9/16" fillet would be laid down in 2 or 3 passes...

Thank You

 

[SnTMan]

To all, I suspect at least part of the confusion is due to the (fairly) recent changes to Part UW-21. I have found that not everybody is up on it.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[gtaw]

Good point, I was basing my comments on the requirements of Section IX and qualifying the WPS. Section VIII could very well impose additional restrictions on the size of the weld. I do not have a copy of Section VIII to confirm if that is the case here.

Best regards - Al

 

[SnTMan]

gtaw, for many years Sec VIII, Div 1 merely required both inside and outside fillets to be equal to the neck thickness. A few years back UW-21 was changed to require a smaller inside and larger outside fillet, thereby rendering many old drawings incorrect

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[gtaw]

Good to know.

Best regards - Al

 

[JStephen]

It looks like the hub diameter at the back of the flange is 12", so if there is no taper, the hub is 5/8" thick- if there is a taper, do you still have room to put a 9/16" weld?

 

[SnTMan]

JStephen, the outside fillet is required to be the lesser of 1.4*tn or the hub small end thickness. Assuming the OP's 9/16" was based on the former, it would be permitted to be less, if equal to the hub small end thickness. Small end thickness of course assumes the hub is tapered. I believe that this is manufacturers option. So, unless you are holding the flange in you hands....

Whoopee.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand