WPS for Furnace PWHT

[Prakash Kumar Bontra]

For furnace PWHT as per ASME B 31.3 all the joints in the spool (1" to 36") need PWHT approved WPS and where to refer?

Prakash Bontra

[Vishwas Keskar]

Pl elaborate your query 

Query is not clear 

Sent from my iPhone

On 27 Jan 2025, at 11:57 AM, Prakash Kumar Bontra <prakas...@gmail.com> wrote:



For furnace PWHT as per ASME B 31.3 all the joints in the spool (1" to 36") need PWHT approved WPS and where to refer?

Prakash Bontra

--
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 visit https://groups.google.com/d/msgid/materials-welding/CANeLWoNy0URXS9X7TEvvZRVe4V-1LNPKwidHJ097fDyPAjyh7Q%40mail.gmail.com.

[Raviraj Gohil]

For Furnace PWHT, All Joints under Heating and Cooling Cycle of Heat Treatment, How to ensure it's joint behaviour if not used WPS with PWHT!

To view this discussion visit https://groups.google.com/d/msgid/materials-welding/9C99E29D-02AE-4D96-87E5-8B83DEE92269%40gmail.com.

[Pipeline Welding]

I refer through other method as below, hope all agree:

Code Requirements for PWHT in ASME B31.3 Clause 331 - Heat Treatment

• 331.1.1: The code specifies that the heat treatment requirements shall apply to welds and heat-affected zones (HAZ) to ensure mechanical properties are achieved as per the base material and design requirements.
• 331.3 - Postweld Heat Treatment:
  • This clause mandates that PWHT is performed as per prescribed methods and conditions, including controlled heating and cooling cycles to relieve stresses and enhance the toughness and ductility of the welds and HAZ.

Importance of Using a WPS with PWHT  ASME B31.3  Clause 328.2.1 - Welding Procedure Qualification

• This clause explicitly requires that all welding procedures must be qualified as per Section IX of the ASME Boiler and Pressure Vessel Code (BPVC). A Welding Procedure Specification (WPS) is qualified using a Procedure Qualification Record (PQR), which includes:
  • The effect of PWHT on mechanical properties (e.g., tensile strength, hardness, impact toughness).
  • The behavior of the weld and base material under cyclic heating and cooling. 

Risks of Not Using a PWHT-Qualified WPS

• • When a WPS is not qualified for PWHT, the following risks emerge:

    • Mechanical Property Degradation: The welds may fail to meet design criteria (e.g., tensile strength, impact toughness, ductility) due to changes in microstructure caused by the heating and cooling cycles.

    • HAZ Cracking: Improper heat treatment can lead to brittle phases (e.g., martensite) or stress corrosion cracking, especially in materials like carbon steel or low-alloy steels.

    • Noncompliance with Code: Not using a WPS that accounts for PWHT violates the procedural qualification requirements under ASME Section IX (QW-407.1) and B31.3 Clause 328.2.1.

[kingslygeo vargheese]

The spools have 1" to 36" Piping joints.

The WPS with PWHT is available only for large diameter / high thickness.

can we do PWHT in the furnace if small size piping joints welded without PWHT WPS which is welding with higher size spools require PWHT?.

To view this discussion visit https://groups.google.com/d/msgid/materials-welding/9C99E29D-02AE-4D96-87E5-8B83DEE92269%40gmail.com.

[patni engineers]

WPS is required .You have to check size range and Qualification .

Pipe diameter , Thickness Range qualified and Required , Grade etc...

Regards

chandrakant

To view this discussion visit https://groups.google.com/d/msgid/materials-welding/CAAR7VZ-G6sd_svwhNprPev55zdMMLPP-GM%3DVKCXFFCrrk%2BCaUw%40mail.gmail.com.