SS 321 LWN Nozzle set-on weld on P11 Base Metal Weld Overlayed with 347 1

[teokal]

Hello guys,

I kindly need your assistance to the below (attached sketch for reference):

As you see, it is a branch (corner) weld (Set-on type) of a SA182 Gr. F321 Long Welding Neck (LWN) with thickness varying from 15,87mm to 27,1mm, to the Pressure Vessel Shell, which is a SA387 Gr.11 Plate, with thicknsess varying from 73mm to 95mm, WITH WELD OVERLAY (W.O.) 347 (on all sides) with overlay thickness 6mm.

The weld is a 321 to 347 W.O., with ER347 and E347 consumables.
The P11 plate with the Weld Overlay, will have been heat treated as per UCS-56, before the branch weld. So, no PWHT due to P11 on the corner weld.
The Weld Thickness is obviously the thickness of the LWN, plus any reinforcements / fillet weld throats.
But my issue is what is the Base Metals thicknesses, in order to correctly support with PQR(s) the WPS.
The one weld member, is again the LWN thickness.
For the other weld member, should one consider:
- Only the 6mm of the 347 W.O.?
- The composite thickness of the Base plate plus the weld overlay of the weld side (95+6=101mm)?
- Or the composite thickness of the Base plate plus both weld overlay thickness (95+6+6=107mm)?

Fabrication according to ASME BPVC Section VIII Div.1, Ed.2021, welding as per ASME BPVC Section IX, Ed.2021.

Thank you in advance for your responses!



Only best result in absolutely necessary time

 

[david339933]

Standard Designation: BPV Section IX
Edition/Addenda: 2019
Para./Fig./Table No: QW-202.4 and QW-424.2
Subject Description: QW-424.2 and QW-202.4(b)(2) dissimilar base metal thickness.- groove welding plate to overlay
Date Issued: 02/04/2021
Record Number: 20-737
Interpretation Number : BPV IX-21-01
Question(s) and Reply(ies):
Background: A production groove weld joint consists of 20 mm thick P-No. 43 plate welded to 6 mm thick corrosion resistant overlay nominally matching the chemical composition of ERNiCrMo-3. The overlay was previously deposited on a 165 mm thick P-No. 1 plate.

Question 1: Does a groove weld PQR showing 10 mm thick P-No. 43 plate welded with ERNiCrMo-3 filler metal support a WPS for the production groove weld described in the background?

Reply 1: Yes.

Question 2: Does QW-202.4(b)(2) apply to the production groove weld joint described in the background?

Reply 2: No. See also interpretation IX-18-11.

 

[r6155]

Be careful.
See:
UCL-31 JOINTS IN INTEGRAL OR WELD METAL
OVERLAY CLADDING AND APPLIED
LININGS

(b) When a shell, head, or other pressure part is welded
to form a corner joint, as in Figure UW-13.2, the weld shall
be made between the base materials either by removing
the clad material prior to welding the joint or by using
weld procedures that will assure the base materials are
fused. The corrosion resistance of the joint may be pro?
vided by using corrosion resistant and compatible weld
filler material or may be restored by any other appropri?
ate means.

Regards

 

[teokal]

Dears david339933 and r6155,

Thank you for your useful responses!
r6155, this paragraph is known, thank you for pointing out. The thing is that the User/Client specifies the LWN to be solid SS material, and welded on the cladding (for their reasons, probably process and theri historical data - I do not know if and how we could avoid their specification). Moreover, it is not clear if the reference to fig. UW-13.2 in UCL-31 is just a schematic reference, because fig. UW-13.2 refers to attachments of Pressure parts to flat plate to form a corner joint. There is no flat plate in our case, it is a rolled plate to form a cylinder. But, of course, thank you for pointing out!
david 339933, thank you for the interpretation, it is very similar to our case, and this is what we intented to do, now you have helped us support it, and thank you for that.


Only best result in absolutely necessary time

 

[r6155]

@ teokal
Please see Table UW-3
(7) Corner joints, full penetration, partial penetration, and/or fillet welded-As limited by
Figure UW-13.2 and Figure UW-16.1 Joint Category C and D Note (8)

Regards