ASME B31.3 PWHT

[anhtrangnghieng]

Dear Experts,

 

Could you please advise me for the following questions:

Question:  Preheat of > 95C (200F) is not used but the weld is made with multiple passes. Is PWHT required for a weld joining P-No.1 materials, when the control thickness is less than or equal to 25 mm (1 inch) but the nominal material thickness is greater than 25 mm (1 inch)?  

Could you please advise me: which thickness, Control thickness or Norminal material thickness, shall be used to determine PWHT requirements & exemptions as per ASME B31.3 ? 

Thank you in advance for any help you can provide.

Regards.

--

PV

[atul khatri]

Hi,

Do you still have some doubt on replies to your query dated 03-Aug having subject "Difference between Control thickness & nominal material thickness ( Para. 331.1.3(c)" ?

Thanks 

Atul Khatri

"

--
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/CADOyxJjGsnNd-ceR_5CGYm%2B%2Bmr2%2B_DTc510xK9Z-Dyo8WhLzUw%40mail.gmail.com.

[anhtrangnghieng]

Dear Sir, 

Please support me to clarify this subject. 

Thanks in advance!

Vào 17:15, T.2, 4 Th11, 2019 atul khatri <atul....@gmail.com> đã viết:

To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CACKOSeD03-9oguL0E1rF4g_VQJt%2BdphM_y43MZEXqKHpiSbCuQ%40mail.gmail.com.

[José Juan Jiménez Alejandro]

To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CADOyxJiODt1KyuHD07v0MEYppm9w-T1PGOJyftB0U1QvaHpuZw%40mail.gmail.com.

--

Ing. José Juan Jiménez Alejandro

Independent Consultant in Parts

and Pressure Equipment

SSI-TPI

Móvil +52 1 812 352 4606

Skype: jjjimeneza

[atul khatri]

Question:  Preheat of > 95C (200F) is not used but the weld is made with multiple passes. Is PWHT required for a weld joining P-No.1 materials, when the control thickness is less than or equal to 25 mm (1 inch) but the nominal material thickness is greater than 25 mm (1 inch)?    

Answer: Since weld is made with multiple pass so PWHT is not required for P-No-1 materials.

Could you please advise me: which thickness, Control thickness or Norminal material thickness, shall be used to determine PWHT requirements & exemptions as per ASME B31.3 ? 

Answer: Its control thickness which decides the requirement of PWHT but the exemption shall be based on nominal thickness.  Here for P-No.1 , for all control thickness its exempted subjected to the requirements of Column 4 of Table 331.1.3 c is met. Similarly for P=no.3 materials PWHT is must for control thickness greater than 16mm but for lesser thickness it can be exempted subjected to the requirements of table 331.1.3.

Regards,

Atul Khatri

To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAO5ZurL%2BPHUv3%3DSGuod48Y7X%2BK1mgRrfHn7u8F1USGwzn1O9Eg%40mail.gmail.com.

[anhtrangnghieng]

Dear Sirs, 

Thanks for your support.

Question:  Preheat of > 95C (200F) is not used but the weld is made with multiple passes. Is PWHT required for a weld joining P-No.1 materials, when the control thickness is less than or equal to 25 mm (1 inch) but the nominal material thickness is greater than 25 mm (1 inch)?    

Answer: Since weld is made with multiple pass so PWHT is not required for P-No-1 materials.

Reply ==> Since the exemption shall be based on nominal thickness. I understand that this case (see attached picture)  PWHT is required ( because nominal material thickness is greater than 25 mm (1 inch) -& preheat 95 deg C not applied ). Please correct me if I am wrong. Thank you.

Could you please advise me: which thickness, Control thickness or Norminal material thickness, shall be used to determine PWHT requirements & exemptions as per ASME B31.3 ? 

Answer: Its control thickness which decides the requirement of PWHT but the exemption shall be based on nominal thickness.  Here for P-No.1 , for all control thickness its exempted subjected to the requirements of Column 4 of Table 331.1.3 c is met. Similarly for P=no.3 materials PWHT is must for control thickness greater than 16mm but for lesser thickness it can be exempted subjected to the requirements of table 331.1.3.

Vào Th 3, 5 thg 11, 2019 vào lúc 14:24 atul khatri <atul....@gmail.com> đã viết:

To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CACKOSeAg%3DAGAnRsmrM2-BAmXNDJr44wPo8AG3UtDpvm8Nv_E%3Dw%40mail.gmail.com.

--