Mr.Vinod, If the high hardness is on the HAZ (I assume it is on the Capping pass) carbon steel side, the probable reasosn may be the hardenability factor associated with carbon steel side. I assume your maximum interpass temparatures would have been less than 150 Deg.C, although not required in your case of dissimilar combination welding, you can very well touch 250 Deg.C. Please check the carbon equivalent (C.E.) of your carbon steel (A 105), with your given thickness of 4.5mm, I feel the C.E. should have been high to cause this higher hardness in the HAZ. Usually forgings tend to have a higher C.E. value. You can try one of the following, 1. Try to weld the capping passes when the interpass temperature is at its maximum (250 Deg.C), and also despoit the first capping pass on the carbon steel side, try deposit the second pass as close as possible to the first capping pass such that the first capping pass and its assiciated HAZ are getting a tempering treatment. 2. If the above practice doesnt work out, then you can do a weld metal build up / buttering using an ordinary carbon steel filler and post weld heat treat the CS part alone, and then you can weld it with your ordinary ER 309 filler to weld the joint, this technique will definitely give you a hardness value within the limits of NACE MR 0175/ISO 15156. Hope this helps, Regards, A.Praveen Muscat
--- On Sun, 2/6/11, Vinod Kataria <vinod.kataria@blissanand.com> wrote:
From: Vinod Kataria <vinod.kataria@blissanand.com>
Subject: Re: [MW:9752] CS to SS welding
To: materials-welding@googlegroups.com
Date: Sunday, February 6, 2011, 4:29 PM
It is on HAZ Carbon Steel side. Regards Vinod Sent from BlackBerry® on Airtel
From: praveen alavandar <praveenakds@yahoo.com> Sender: materials-welding@googlegroups.com Date: Sat, 5 Feb 2011 05:46:59 -0800 (PST) To: <materials-welding@googlegroups.com> ReplyTo: materials-welding@googlegroups.com Subject: RE: [MW:9743] CS to SS welding
| Dear Mr.Vinod, Where do u get the higher hardness? Is it on the weld or HAZ? whether it is on the root or on the cap? If possible you can attach your macro photo identfying the higher hardness location. Regards, A.Praveen Muscat
--- On Sat, 2/5/11, Vinod Kataria <vinod.kataria@blissanand.com> wrote:
From: Vinod Kataria <vinod.kataria@blissanand.com>
Subject: RE: [MW:9740] CS to SS welding
To: materials-welding@googlegroups.com
Date: Saturday, February 5, 2011, 2:49 PM
Please note the required details as per the following in RED colour:- * Welding Process – GTAW for Root and Filling with SMAW.
* Thickness of the materials (Dissimilar weld ?) – 4.5mm.
* Welding Technique– String, cup size 6mm, multipass, single electrode.
* Preheat temp. – 20 degree C min.
* Heat Input– 0.95 to 1.19 KJ/mm.
With kind regards, Vinod Kumar Kataria GM - Operations Bliss Anand Private Limited, 92B/93B Sector 5 IMT Manesar,Gurgaon, National Capital Region Delhi. India . Phone : +91-124-4366000 (9 Lines) Mobile Phone : +91-9560199004 Fax : +91-124-2290884 From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of manpreet
Sent: Saturday, February 05, 2011 7:58 AM
To: materials-welding@googlegroups.com
Subject: Re: [MW:9737] CS to SS welding Dear Vinod,
Ok then, I would like you to provide some more info.
* Welding Process
* Thickness of the materials (Dissimilar weld ?)
* Welding Technique
* Preheat temp.
* Heat Input
Changes may be required for above stated factors (in lieu of PQR) to overcome this problem.
Regards
Manpreet Singh
On Sat, 05 Feb 2011 01:15:21 +0530 "Vinod Kataria" wrote
> Dear Manpreet, Thanks for your valuable time. Please note we have qualified PQR using Filler 309L only but so many time we are getting more than 22 HRC which is not acceptable as per Nace MR 0175. With kind regards, Vinod Kumar Kataria GM - Operations Bliss Anand Private Limited, 92B/93B Sector 5 IMT Manesar,Gurgaon, National Capital Region Delhi. India . Phone : +91-124-4366000 (9 Lines) Mobile Phone : +91-9560199004 Fax : +91-124-2290884 From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of manpreet
>Sent: Friday, February 04, 2011 3:17 PM
>To: materials-welding
>Subject: Re: [MW:9727] CS to SS welding Dear Vinod,
>
>When welding Carbon steel to stainless steel, one should avoid formation of martensite by using overalloyed filler metal (309L) which willformAustenite even when cooling,a Preheatingand using Temper bead technique would also be helpfull to reduce Hardness,
>
>Considerationmust be given to reduce High Dilution by reducing Travel Speed, buttering the joint face, no SAW etc.
>
>Also refer to the Shaeffler Diagram to evaluate what kind of microstructue you would expect, with filler metal E309L, you can expect "Austenite with little ferrite".
>
>Regards
>Manpreet Singh
>
>
>
>On Fri, 04 Feb 2011 13:18:26 +0530 "Vinod Kataria" wrote
>> Hi, How to control the hardness for NACE MR 0175 application if we have to use A-105 flanges on SS-316 Chamber as PWHT cannot be done. With kind regards, Vinod Kumar Kataria -- >>To post to this group, send email to materials-welding@googlegroups.com >>To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com >>For more options, visit this group's bolg at http://materials-welding.blogspot.com/ >>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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>
 --
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For more options, visit this group's bolg at http://materials-welding.blogspot.com/
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. --
To post to this group, send email to materials-welding@googlegroups.com
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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.
| -- To post to this group, send email to materials-welding@googlegroups.com To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com For more options, visit this group's bolg at http://materials-welding.blogspot.com/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. -- To post to this group, send email to materials-welding@googlegroups.com To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com For more options, visit this group's bolg at http://materials-welding.blogspot.com/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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