Re: [MW:34237] SS GTAW Welding without Back purging.

For GTAW welding -Single Vee - 33.4 OD, Full GTAW welding -

SS TO SS Welding or Cr > 3 % , backing gas is required to get sound root without any Oxidation.

The Oxygen is excluded by purging Argon/Helium or other Inert mixtures at root side to avoid Oxidation .

The root side is inaccessible due to small diameter in your above case.

Backing gas shall be continued till 6mm deposit is welded . This is not a Code requirement but followed as a good engineering practice across industries

Thanks

Vishwas

On Monday, May 22, 2023 at 4:51:37 PM UTC+5:30 Anand Elankumaran wrote:

Hi Mr. Vishwas Keskar,

Single Vee butt weld - Root/Hot/fill/cap- full GTAW

pipe OD -33.4 mm

On Mon, May 22, 2023 at 7:47 AM Vishwas Keskar <vvkes...@gmail.com> wrote:
Are you intending to qualify PQR in
Single Vee butt weld - No welding from Root side ?
Double Side Weld with back grinding DPT from root side ?
This will decide the PQR purging requirement

Thanks

Vishwas
IWE

Sent from my iPhone

On 22-May-2023, at 8:40 AM, Anand Elankumaran <email2...@gmail.com> wrote:

Dear experts,

Could you please check and advise the below query.

Whether the back purging is a quality requirement or the ASME code is insisting on back purging on SS material while doing the GTAW process.

Whether we can qualify SS -GTAW PQR without back purging or the ASME code does not allow doing PQR for austenitic steels without a back purge?
Kindly advise how to do it without purging in SS GTAW Welding . Planning for PQR as well

--
Thanks and Regards,
E. Anand,
Lead QA-QC,
Sohar,
Oman.

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
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-weld...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CANOYChxEbF6gP%2BwCFusuTWnJpmbZMst%2BM1qCz3y2fHr0mRaY1Q%40mail.gmail.com.

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
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-weld...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/089B4A0A-1805-4EF9-BAF3-AC2527879802%40gmail.com.

--
Thanks and Regards,
E. Anand,
Lead QA-QC,
Sohar,
Oman.

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
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 view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/81326b99-027e-4e94-855a-f41ac118514cn%40googlegroups.com.

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...

Materials & Welding

Search This Blog