Skip to main content

[MW:31375] RE: 31371] PWHT Thickness Requirements.

By Materials & Welding

Hi ,

Which version of B31.3 code you're following , 2018 or older?. You may still avoid PWHT, if the design code is of 2018 edition. See the exemption clauses from B31.3 -2018 as highlighted.

Note: If PWHT is mandated by design or process condition, e.g. sour service or other conditions, PWHT is mandatory irrespective of thickness. The  designer has to specify that in the drawing.

All appropriate clauses are highlighted for better understanding. Hope this would help you.

 

Thanks.

 

 

Pradip Goswami, P.Eng, IWE

Consultant-Welding-Metallurgical Engineering

 

Cell & Whatsapp-905-9793232.

Personal:pgoswami@rogers.com

 

 

 

From: materials-welding@googlegroups.com <materials-welding@googlegroups.com> On Behalf Of Andrew Ubakwem
Sent: August 31, 2020 10:10 AM
To: materials-welding@googlegroups.com
Subject: [MW:31371] PWHT Thickness Requirements.

 

Dear all

 

Pls what is the current thickness requirements for PWHT as per ASME B31.3? 

 

I came across old version of the code, it specifies that PWHT not required for all P1 materials, provided min preheat is maintained at 95deg'C.

 

We intend welding; 18" sch 80(23.83mm) to ASTM A 106, 24" sch 80(30.8mm), is PWHT required? Cite relevant Code sections Please.

 

Regards,

 

Andrew. 

--
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/CAK1J--O6jttEt5bS1QCjykeCFnGeJpwoKsBqPPt9M_P1dOx%3DrA%40mail.gmail.com.


Virus-free. www.avg.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