Skip to main content

Re: [MW:34222] SS GTAW Welding without Back purging.

By Materials & Welding
There are some articles with  GMAW -RMD process on stainless steel without purging gas , even with GTAW by using flux coated wire and flux paste u can do welding without  without purging gas in place , but client acceptance to be taken by using qualified PQR'S in place before procedding for this and it takes time for approval.
in common SS to SS welds always required back purging .
there are some cases of CS# SS doesnot required any back puring during root welding. 

Thanks & regards, 
Srinivas Rao
welding Engineer 

On Monday, May 22, 2023 at 8:31:03 AM UTC+4 Kannayeram Gnanapandithan wrote:
Except for Reactive metals, others are optional, while qualifying PQR, u have to keep it in about referring codes requirements. As general engineering practice, if Cr is more than 3%, it is always better to have back purging to avoid oxidation.

THANKS & BEST REGARDS,
KG.PANDITHAN, BE, IWE,  CSWIP 3.1,
ISO 9712 Level 2 in VT,
ASNT-Level II in PT,MT,RT & UT,
LA ISO 9001-2015,
International Welding Engineer. 
CONSULTANT-WELDING & QUALITY
Mobile no: +919940739349


On Mon, May 22, 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-welding+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/b3f3c1b2-2f18-4cfc-9746-a1c85c3366b5n%40googlegroups.com.

Comments

Post a Comment

Popular posts from this blog

Re: [MW:34105] SA266 GR4N 4 Cycle SPWHT

By Materials & Welding
Hi,  You are correct, Minimum refers to the one cycle for which this part will expose until final work shop PWHT. hence mill test certificate shall include this.  Max. SPWHT, refers to additional cycles of heat treatment that are reserved for future repairs during equipment lifetime.  Again, these simulated no. Of cycles shall be specified in MTC.  The idea is we need to make sure that steel mechanical properties are not compromised upon exposure to multiple repairs (i e 4 cycles in your case).  One could say, if steel is subjected to 4 cycles and is ok, then it should by defacto be good for one cycle, yet, this is wrong assumption cause mechanical problems and microstructure of materials varies accordingly based on no. Of cycles for which material will expose. This is apparent in alloy steel and especially for impact test values as an example.  In your case, this forged CS with properties before PWHT can be understood to be " as forged" condition (i.e. Wit...
Post a Comment
Read more

Materails FAQs

By Materials & Welding
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...
21 comments
Read more

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

By Materials & Welding
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...
Post a Comment
Read more