PWHT - ASME BPVC Sec I - Boiler

[TOMMY2010]

Dear Gents,

- Welding of this support needed to this reinforcing pad in a Power Boiler that is constructed according to ASME Sec I, In this situation with the all parameters indicated in the picture (Weld Size, Materials and Thickness ),

My question is about Preheating or PWHT Requirements according to the code ? What would you do in this situation with unassigned material included ?

Thanks in advance

 

[Dhurjati Sen]

What do you call the plate that is above the reinforcing plate?

As the welding is in no way connected to the plate that is welded to the boiler, no PWHT is required.

Not to worry about the unassigned material, it is equivalent to ASTM A 283 and has higher strength than ASTM A 36.

DHURJATI SEN

 

[TOMMY2010]

- For your question, above the plate its the Main Lower Header fot that boiler and its not a plate it's a "Header"

- Your speech from the engineering point of view is perfect but from the codes point of view i think we need to go deeper so let me discuss three solutions or 3 thoughts that I already have in mind and if you can help me to decide which one we can go with - but this time with evidence and quotations as possible.

- we need to Weld [S275JR Thk. 40mm to SA516Gr.70 Thk. 35mm), The first one is unassigned and the 2nd one is a P1 Group 2 material according to ASME SEX IX - Table QW-422

Solution 1, I already know for sure that this steel S275JR has an equivalent - as a low ally Carbon steel - with some ASME materials as you said but its not identical to any ASME materials and according to ASME IX, QW-424.1 Which States "any unassigned metal to any P‐Number metal" - which is my case - then the base metal qualified will be "The unassigned metal to any metal assigned to the same P‐Number as the qualified metal" and because i already have a welding book that has many WPSs but neither of them covers my case so i have to prepare a new WPS as per ASME.
If i proceeded with this solution i am facing another problem, will this joint require PWHT or not ?
- According to ASME Sex I, i have to know which P NO to go inside ASME Sex I and find the PWHT or Preheat requirements ( For an unassigned materials there is no P No ) so we stopped here

- Solution 2 , Seems to be very strange but its logic somehow
The joint is not touching any pressurized parts and using the structural steel S275JR just for supporting the boiler not for bearing high pressure as in pressurized parts and i have many structural steel WPSs that are qualified according to AWS D1.1
If I Proceeded with this solution i am facing another problem that all my welders in this job are qualified according to ASME IX not AWS D1.1 and i have to requalify some welder according to AWS D1.1 to be able to weld all boiler supports

- Solution 3, Which i can't do even every body try to push me to, Considering the materials as a P.No1 material and using the P No.1 To P No.1 WPS and proceed with/Without PWHT ? but i have no reference that says i can use this procedure

What do you think
Thanks for your reply and interest.

 

You're asking the interweb to do your job for you...

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[Dhurjati Sen]

1. By looking at the reinforcing plate it seemed to me that it can't be 35 mm thick (must be more), but your re-confirmation makes things good.

2. You like to carry out things strictly as per code, and I do not object to it.

3. Solution 2 suits you, your welders would easily qualify as per AWS and making a PQR & WPS won't take up much time.

4. I would have gone for Solution 3, but it is already beside the point and I won't be pushing you for it.

Good thinking on your part.



DHURJATI SEN

 

[weldstan]

AWS D1.1 does not apply unless required under a specific contract. PWHT is not required for the weld in question; however, preheat should be done at 200 F minimum to mitigate potential for hydrogen induced cracking.

 

[TOMMY2010]

@ironic metallurgist. Recently, Interweb - in your case - have no replies for a real world issue and seems to be busy making some sort of phrases and expressions Thx for your useful and effective comment and from your point of view, Next time i won't ask.

@Dhurjati Sen , Thx too much for your replies

1.The answer to your question is that the Plate attached to the header is 35mm as per vendor drawings and if it may help you the joint above out joint (The header to the 35 mm plate) according to the drawings has a 30mm leg length.

2.In ASME Sec I, I found this paragraph which can eliminate any chance of using this solution "PG-55 SUPPORTS AND ATTACHMENT LUGS" which some how states that even supports should be carried out according to the codes "And i am waiting for you confirmation of that if you agree".

@weldstan, Thx mate and i already checked and you are 100 % Correct and thx for reminding me of that,

 

Actually ME, I am too busy with my own real world issues to be doing online charity work.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[TOMMY2010]

- @ironic metallurgist, Since I don't know how to back off such productive discussion with you, please let me remind you that you with your free will entered this thread and commented on it and no one forced you to do that so as you said you don't do charity work so it would be a smart and logic move not to enter or comment my thread or any other threads and it may be smarter to stay focused at your real world issues and let other helpful and respectful forum members to answer questions and exchange their knowledge for "charity " as they do this with their free will and this is one of the purposes of this lovely forum

I hope not to see you again
Thanks