Skip to main content

Re: [MW:24023] Re: PQR - WPS - PWHT P91 to CS

Lower critical temp for CS is 723 degree Celsius, how u can allow it to 740

THANKS & BEST REGARDS,
KG.PANDITHAN, IWE,  AWS-CWI, CSWIP 3.1,
CONSULTANT-WELDING & QUALITY

On Thu, Dec 31, 2015 at 11:02 AM, Chandrakant Vaidya <clvaidya.2010@gmail.com> wrote:
Greetings.
In my view the CS temp.attachments can be welded with Gr 91 mtrl.but not job mtrl.as rightly stated by Pradip & Zakeria.
Regards
C.L.Vaidya

On Saturday, October 20, 2012 at 3:59:03 PM UTC+5:30, Tunisian Quality Engineer wrote:
Dear experts,

  Need your support.

We performed one PQR P91 grade ( P number 15E) to Carbon steel (P number 1) welded GTAW/SMAW ER90S-B9 / E9015-B9, 11mm thickness, PWHT @ 740°C - 40 minutes.

PQR and related WPS already approved by our client. but the Owner consulting agency sent to us some comments :

1- No possible to weld P91 directly to CS shall add transition material P11 grade : We answer that it's design issue and i requested some explain / calculation from design.

2- Should use filler metal compatible with lower grade material : i answer that can make choice of  filler metal between to material grades (included) so we can weld with lower, heigher or iontermediate filler metal when mechanical properties is ok and don't have ebjection from project spec.

3- this is the main issue : PWHT @ 740 °c is heigher than lower critical temperature for CS so we must perform PWHT in intermediate Temperature : in this case if will do like this WPS will not supported by Prepared PQR;

PQR approved by Client and weld already done, i propose to perform hardness test, PMI and metallographic replic in production ( just one weld) to confirm.


Need your support .



Regards.





--
زكرياء غراب
GHRAB Zakaria

--
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To post to this group, send email to materials-welding@googlegroups.com.
Visit this group at https://groups.google.com/group/materials-welding.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/8e8fded5-7f59-4ab2-8b7f-7e3e19baa019%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

--
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To post to this group, send email to materials-welding@googlegroups.com.
Visit this group at https://groups.google.com/group/materials-welding.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAJzm4eNSSFfunj%2BBauBMXqo7scbCA_ZtQAFiWm2ucVEGDN91JA%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.

Comments

Popular posts from this blog

Heat tint (temper) colours on stainless steel surfaces heated in air // Heat tint

Introduction The colour formed when stainless steel is heated, either in a furnace application or in the heat affected zone of welds, is dependent on several factors that are related to the oxidation resistance of the steel. The heat tint or temper colour formed is caused by the progressive thickening of the surface oxide layer and so, as temperature is increased, the colours change.   Oxidation resistance of stainless steels However, there are several factors that affect the degree of colour change and so there is no a single table of colour and temperature that represents all cases. The colours formed can only be used as an indication of the temperature to which the steel has been heated. Factors affecting the heat tint colours formed Steel composition The chromium content is the most important single factor affecting oxidation resistance. The higher the chromium, the more heat resistant the steel and so the development of the heat tint colou...

Materails FAQs

Q: What are equivalents for standard Q 235 B (and Q 235 A) for U-channels? (asked by: boris.vielhaber@vait.com) A: DIN Nr. = 2393 T.2, 2394 T.2, EN 10025 W. Nr. DIN 17007 = 1.0038 Design DIN 17006 = RSt 37-2, S235JRG2 (Fe 360 B) Q: What is St DIN 2391 BK material? (asked by: dmcandrews@automaticstamp.com) A: Precision steel tubes, cold-finished/hard. Q: What is C.D.W. Boiler Tube? (asked by: montydude123@yahoo.com) A: Cold Drawn Welded Boiler Tube. Q: WHAT IS W.Nr. 1.4301? PLS TELL US IN EASY LANGUAGUE (asked...

The Schaeffler and Delong diagrams for predicting ferrite levels in austenitic stainless steel welds

Introduction Ferrite is important in avoiding hot cracking in during cooling from welding of austenitic stainless steels. 'Constitution diagrams' are used to predict ferrite levels from the composition by comparing the effects of austenite and ferrite stabilising elements. The Schaeffler and Delong diagrams are the original methods of predicting the phase balances in austenitic stainless steel welds. Nickel and chromium equivalents A 'nickel equivalent' is calculated for the austenite stabilising elements and a 'chromium equivalent' ferrite stabilising elements. These are used as the axes for the diagrams, which show the compositional equivalent areas where the phases austenite, ferrite, martensite (and mixtures of these) should be present. Although intended to show the phase balance of weld fillers, these diagrams can also be used to illustrate the phase balance of the 'parent' material. There are different diagrams for dif...