In such case, it is better to approach client with all justification and docments and require to convince client , stating no deviation from code and spec.assuring to achieve all required test result
Also test the plate with revised simulation for impact value by which you can convince better
Regard
Hegde
Dear all
There is a clause in Saudi Aramco documents stating as below
The maximum PWHT soaking temperature for quenched and tempered carbon steel and C-1/2Mo shall not exceed the temperature at which the test pieces were heat treated as shown on mill test reports or 650 deg C max for carbon steel ,690 deg C max for C-1/2 Mo and 700 for low Chrome alloy.
Our material is SA-387-Gr 12 cl2 (C -1/2Mo) which is P4 material. The min PWHT temp as per code (VIII Div 1-U stamp) is 650 deg C.
Now aramco has commented on our documents that they need a PWHT temperature to be 25 deg C less than tempering temperature as specified on MTC for the plates. So we need to have a tempering temp of min 680 deg C so we can carry out the PWHT at 650 deg C but he plates MTC shows the tempering temp as 660 so we are 15-20 deg below. The plates are already purchased which are 65,70,80 mm thick.
My first query is no where in the aramco document we can find a clause of have PWHT temp 25 deg C less than tempering then what is the reason for asking this requirement.
What is the solution that we can offer them.
Regards
Thaksen
Also test the plate with revised simulation for impact value by which you can convince better
Regard
Hegde
Sent from my BlackBerry® smartphone from !DEA
From: THAKSEN INGOLE <t_ingole@yahoo.co.in>
Sender: materials-welding@googlegroups.com
Date: Thu, 2 Sep 2010 15:27:03 +0530 (IST)
To: material welding<materials-welding@googlegroups.com>
ReplyTo: materials-welding@googlegroups.com
Subject: [MW:6831] tempering temperature of P4 material
Dear all
There is a clause in Saudi Aramco documents stating as below
The maximum PWHT soaking temperature for quenched and tempered carbon steel and C-1/2Mo shall not exceed the temperature at which the test pieces were heat treated as shown on mill test reports or 650 deg C max for carbon steel ,690 deg C max for C-1/2 Mo and 700 for low Chrome alloy.
Our material is SA-387-Gr 12 cl2 (C -1/2Mo) which is P4 material. The min PWHT temp as per code (VIII Div 1-U stamp) is 650 deg C.
Now aramco has commented on our documents that they need a PWHT temperature to be 25 deg C less than tempering temperature as specified on MTC for the plates. So we need to have a tempering temp of min 680 deg C so we can carry out the PWHT at 650 deg C but he plates MTC shows the tempering temp as 660 so we are 15-20 deg below. The plates are already purchased which are 65,70,80 mm thick.
My first query is no where in the aramco document we can find a clause of have PWHT temp 25 deg C less than tempering then what is the reason for asking this requirement.
What is the solution that we can offer them.
Regards
Thaksen
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