Dear Rao,
If I understand your problem correctly, the vessel is 410S Clad+ 387 Gr11 Cl2 backing material. The internals are of 410S.S.The design code is ASME Sec-VIII, DIV-1.
You have not mentioned if any added specifications such as, NACE MR-01030-2007, Materials Resistant to Sulfide Stress Cracking in Corrosive Petroleum Refining Environments or API-582-Recommended Practice Welding Guidelines for the Chemical, Oil, and Gas Industries is applicable.
Typically welding on clad vessel could be executed with a couple of options (I am referring to the S.S clad welding only) :-
A. Clad Restoration through - Austenitic+Ferritic/Martensitic Electrodes:-
1. Barrier layer, E309L+ Rest E-410-XX electrodes. The maximum “C” for 410 S.S weld metal is 0.12%.If you could get electrodes with “C” lower than this value but meeting all the requirements of SFA 5.4 it may be better, from avoiding any chloride or sulphide SCC mechanism. This route is usually the most cost effective way for 410/410S clad welding But sometime for pressure vessels due to complexities this technique would not be feasible.
B. Clad Restoration through - Complete Austenitic Electrodes
1. Total clad welding with 309L.This is very common option, however the one of the problems(Ferrite and Simga phase in service) is highlighted by Mr Prabhukumar below. Welding with complete 309L welded metal can introduce service cracking related problems due to higher co-efficient of linear expansion of austenitic weld metal. Plus in chloride media 309L weld metal would not be advisable.
2. Total clad restoration with Inconel 182 or equivalent (E-NiCrFe-3) electrodes. This would be preferred option if on chooses all austentitc weld metal. Due to higher cost on inconel this may be expensive. But at the same time Inconel-182 have a coefficient of thermal expansion similar to Ferritic 410S.S. Hence service induced thermal stresses which may be experienced with E-309L weld metal would be avoidable. If the operating temperature is over 3150C(6000F) designer should better confirm this thermal stress issue. API -582 recommendation is not to use 309L weld metal above this design temperature.
If the vessel is a coke drum which experiences frequent quench cycles Inconel-182 (E-NiCrFe-3) consumables are be recommended by many clients.
C. Welding of internals :- May be performed either my matching 410 S.S electrodes or Austenitic E-NiCrFe-3 electrodes. E-309L may be avoided if there are concerns as mentioned above. If you decide to stick to 410 S.S electrodes, ensure the max “C” content and hardness (if applicable).
I would say considering all aspects Inconel-182 option ( B-2) would be better suited, than E-309L option. E-309L or matching electrodes may be used, if design temperature, ferrite/sigma phase, chloride environment , etc these issues are resolved.
PWHT Temperature:- As per Sec VIII, DIV-1, for P4 (387 Gr11 Cl2) nominal PWHT is 6500C while for 410S.S(P6) it is 7600C. In order to strike a balance (i.e. to stress relieve the internal welds properly) PWHT upon completion may be required to be done above 6500C.
Typical 410 S.S welding requirements:-
· Clad Overlay (with Austenitic Electrodes)—Preheat 1250C max, interpass 1750 C max for barrier layer only, rest of the layers preheat would not apply, but interpass 1750 C max shall be maintained.
· Rest of the 410S.S welding - Preheat 1500C max, interpass 230-2500 C max
I have attached some literature on 410 clad welding for Voest-Alpine. Look through page 26-31 for info on clad welding.
Thanks.
Pradip Goswami,P.Eng.
Welding & Metallurgical Engineer/Specialist
Ontario Power Generation Inc.
Email-pgoswami@sympatico.ca,
Dear Sir,
As per table UHA-32 of ASME VIII Div.1 (Post weld heat treatment requirement of P.No.7 Materials) a preheat of 230 deg.C is required if thickness of SS 410S is above 10mm when Austenitic consumables are used.
I have selected 309L type consumable for Welding of SS410S material. Job internal piping thickness exceeds 10mm.
For Overlay/Restoration, i selected 309L consumable with Preheat of 150 Deg.C, interpass of 250 Deg. C. Is it Ok?
I'm confused especially with Code requirement & information from net regarding welding of SS410S material.
I request to provide more information on the same subject with respect to code requirement in welding of SS410s material.
regards
P.Rao
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Prabhu Kumar L
Sent: Monday, June 28, 2010 1:00 AM
To: materials-welding@googlegroups.com
Subject: [MW:5766] RE: 5765] RE: 5751] Welding of SA 240 TP 410S material.
Dear Rao,
As Mr. Hegde mentioned in the trailing mail, it is suggested to use Ni based filler metals instead of E309L type for welding of SS410S materials. In general, 309 type filler metal should not be used for temperature above 600 Deg. C, due to sigma formation (Brittle phase) in the welds.
Basically this electrode shall produce higher ferrite content around 20% in the welds, which will convert into brittle sigma phase when temperature above 500 Deg. C. Sigma phase would reduce the toughness and ductility and will increase hardanability and hardness of the weld metal.
In your case, piping (SS410S) and complete vessel undergoes PWHT as per Code requirement and hence it is preferred to use ENiCrFe-3 for CR overlay and ERNiCr-3 type filler metal for piping materials.
If PWHT can be avoidable for SS410S materials, you can use E309L type filler metal. Refer to API RP582 for recommendation of selection of welding filler metal based on temperature limits.
Regards,
L. Prabhu kumar,
Sr. Principal Engineer,
Equipments & Materials Dept.,
Saipem India Projects Limited,
Nungambakkam High Road, Chennai - 600 034, India.
Tel:+91 44 43906588, Ext.: 588, Fax:+91 44 66840345,
Mobile Ph. No.: +91 9003010978.
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of PB HEGDE
Sent: Monday, June 28, 2010 9:24 AM
To: materials-welding@googlegroups.com
Subject: [MW:5765] RE: 5751] Welding of SA 240 TP 410S material.
Hi!
As base metal is of LAS , req PWHT at min 650C , Therefore suitable consumable for clad restoration of 410 S clad is E NiCr fe3 or NiCr Mo3
Preheat Temp . of base metal for barrier layer is 100 C , (No need of preheating for subsequent layers. min ,Interpass temp is 175 max, Welding Current – 110-120 Amp for 3 .2 dia electrode.
Regards
Hegde
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of P.Rao
Sent: Saturday, June 26, 2010 5:21 PM
To: materials-welding@googlegroups.com
Subject: [MW:5751] Welding of SA 240 TP 410S material.
Dear all,
Can any body share the experience in welding of SA240 TP410 Material.
I have a Vessel consists SA387 Gr.11 Cl.2 material cladded with SS410S.
Internal Piping material : SS410S thickness 10-15mm.
Construction Code : ASME SEC VIII Div.1.
Welds in SS410S will under PWHT of low Low alloy steel.
Need guidance in Preheat & interpass temperature of SS410 material welding (Consumable selected for welding of SS410S is 309L type).
regards
P.Rao
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The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
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The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
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