Mza.16261
Structural
- Aug 23, 2023
- 3
Dear Esteem Forum Members,
May I request your expertise and professional inputs on my following issue.
aa) We have received a job order from a client to replace HP Bypass valve outlet tube of a HRSG. A qualified WPS which was used to install the HP Bypass Valve outlet tube to the steam pipe during the fabrication of the HRGS was attached to the job order. So, I studied the WPS and learnt that HP Bypass Outlet Tube (ASTM A335 P22 Grade) is P No. 5A and the Steam Pipe (ASTM A335 P5 Grade) is P No. 5B. The essential variables of the WPS are mostly correct except PWHT temperatures.
bb) I checked the PWHT requirement of the WPS with ASME B31.1:2020 Para. 132, Sub-Para 132.1, 132.2, 132.3 as well as Table 132.1.1-1 Postweld Heat Treatment and Table 132.2-1 Exemptions to Mandatory Postweld Heat Treatment. The, I learnt that the HP Bypass Outlet Tube (ASTM A335 P22 Grade, P No. 5A) may be exempted from PWHT because of the thickness is lesser than ≤5∕8" (16 mm) but for the Steam Pipe (ASTM A335 P5 Grade, P No. 5B),PWHT is mandatory.
cc) I raised the issue to the client mentioning the WPS is NOT valid to perform the requested job order and asked to requalify the WPS in accordance with the mandatory PWHT requirements per B31.1:2020 or to provide a new WPS.
dd) The client passed the issue I raised to the original fabricator of the HRSG. The fabricator replied to the client as following: "the WPS is acceptable and can be used because PWHT holding temp. range for P-No. 5A material and P-No. 5B material are the same; P-No 5A material (HP Bypass Valve Outlet Tube) is exempted from PWHT for thickness lesser than 16 mm; therefore, PWHT for P-No. 5B material (steam pipe) is not required for WPS qualification".
ee) Then referring the fabricator's reply , the client affirm that the WPS is valid and insists to use that WPS for the requested job order. So, I replied to the client that we cannot provide the requested service unless a new or a requalified WPS with PWHT parameters are provided.
My question is whether my knowledge and understanding about mandatory PWHT requirement of P-No. 5B is correct or the original fabricator's point of view is correct. For your reference I attached files.
Best regards with the highest appreciation for your kind inputs,
Mza.16261
May I request your expertise and professional inputs on my following issue.
aa) We have received a job order from a client to replace HP Bypass valve outlet tube of a HRSG. A qualified WPS which was used to install the HP Bypass Valve outlet tube to the steam pipe during the fabrication of the HRGS was attached to the job order. So, I studied the WPS and learnt that HP Bypass Outlet Tube (ASTM A335 P22 Grade) is P No. 5A and the Steam Pipe (ASTM A335 P5 Grade) is P No. 5B. The essential variables of the WPS are mostly correct except PWHT temperatures.
bb) I checked the PWHT requirement of the WPS with ASME B31.1:2020 Para. 132, Sub-Para 132.1, 132.2, 132.3 as well as Table 132.1.1-1 Postweld Heat Treatment and Table 132.2-1 Exemptions to Mandatory Postweld Heat Treatment. The, I learnt that the HP Bypass Outlet Tube (ASTM A335 P22 Grade, P No. 5A) may be exempted from PWHT because of the thickness is lesser than ≤5∕8" (16 mm) but for the Steam Pipe (ASTM A335 P5 Grade, P No. 5B),PWHT is mandatory.
cc) I raised the issue to the client mentioning the WPS is NOT valid to perform the requested job order and asked to requalify the WPS in accordance with the mandatory PWHT requirements per B31.1:2020 or to provide a new WPS.
dd) The client passed the issue I raised to the original fabricator of the HRSG. The fabricator replied to the client as following: "the WPS is acceptable and can be used because PWHT holding temp. range for P-No. 5A material and P-No. 5B material are the same; P-No 5A material (HP Bypass Valve Outlet Tube) is exempted from PWHT for thickness lesser than 16 mm; therefore, PWHT for P-No. 5B material (steam pipe) is not required for WPS qualification".
ee) Then referring the fabricator's reply , the client affirm that the WPS is valid and insists to use that WPS for the requested job order. So, I replied to the client that we cannot provide the requested service unless a new or a requalified WPS with PWHT parameters are provided.
My question is whether my knowledge and understanding about mandatory PWHT requirement of P-No. 5B is correct or the original fabricator's point of view is correct. For your reference I attached files.
Best regards with the highest appreciation for your kind inputs,
Mza.16261