Question about a particular flange weld "overlay"

[timsch]

I have attached a file showing a section of a weld-neck flange that has three weld overlays per customer requirements. Two overlays are on the bore, while a third is shown in the hatched section at the tapered end of the weld-neck. It is this third that I need to know to categorize because I will need to create a weld procedure for this weld. After all overlays are applied, this flange will be butt-welded to a reducer.

The flange base material is F11, and the third overlay is to be an Inconel. As far as pressure boundary goes, the Inconel will not be supported by base metal under pressure. The longest horizontal length of this overlay is around 1/2". Looking at UCL-40, the weld procedures listed don't seem to match this configuration. It seems that UCL-42 could apply, but this is not simply a groove joint made with corrosion resistant filler metal. However, UCL-42 seems the closest approximation to what I'm dealing with. Would a standard WPS for groove welds cover this third overlay?

Thanks

 

[CWEng]

The area on the end of the fitting is not overlay, it's buttering, as the term is used in ASME Section IX. You can qualify it with a buttered P4 plate/pipe (likely given PWHT), then welded to the reducer. PWHT could be after the 2nd part of the weld if the reducer requires PWHT as well.

 

[metengr]

Your current diagram does not depict a butter layer, it shows the entire weld prep end being entirely deposited with Inconel, no different than a groove weld made with Inconel. If it is buttering, which you intended, that is fine but you need to show that instead of a solid cross hatched section.

 

[timsch]

metengr, This is a customer supplied drawing, with all weld configurations designed on their end. I did not intend it to be a buttering weld; any wording implying such is just my lack of a more appropriate term to describe this weld. I am just tasked with making sure we have a WPS for the end prep or create one if needed.

I am glad to see you state that it is no different than a groove weld, since that will allow me to use an existing WPS for groove welding rather than create another one for some type of overlay weld.

 

[CWEng]

Forgive me if I misunderstood the drawing, but it sure looks like the welded end of a weld neck flange. If that's not the case, then fine, but if that is the case, and the weld neck flange is going to be joined to a pipe or other fitting, then it should be considered buttering, whether you, or another company is going to weld something to it. Butting can be qualified by groove welding, but has to follow the rules of QW-283.


Per ASME Section IS: buttering: the addition of material, by welding, on one or
both faces of a joint, prior to the preparation of the joint
for final welding, for the purpose of providing a suitable
transition weld deposit for the subsequent completion of
the joint.

 

[timsch]

CWEng, you did not misunderstand; it is a WN flange. Forgive me for neglecting to comment on your initial post.

The deposited weld that metengr has called the weld-prep is about 1/2" in length. To me, that is well beyond what I've consider a butter layer would be, but I'm no expert. All of the butter layers I've dealt with in the past were of a uniform thickness, and rather thin at that compared to the remaining welds. The butter layer also has conformed to an existing machined profile rather than being machined itself after being deposited. These two factors had me 2nd guessing whether this qualified it as some other type of weld. That being said, the definition of buttering in Section IX certainly doesn't limit it like I have in my mind.

EDIT: removed erroneous statement about PWHT

 

[weldstan]

What is the material or overlay of the reducer? Is it the same as that of the flange?
Assuming that the nickel base filler is used for corrosion protection as well as providing a suitable transition joint, I would recommend qualifying an overlay procedure. Years ago a Section IX Interpretation seemed to address a similar issue.

 

[timsch]

The base metal of the flange is F11, the overlay is Inconel 625, and the connecting reducer is 321. Thanks everyone for the input.