Several responses have been incorrect on one point. It is possible to write a WPS for both conditions, with and without PWHT. Both conditions must be properly supported by appropriate PQRs. One very typical method is to perform the test welding on a coupon twice as long as would be necessary for a single qualification. This plate is subsequently split into two plates with one half given the PWHT. Both plates as welded and PWHT’ed are tested per the Code and whatever other requirements are desired. I have seen this done with carbon steels and sometimes stainless steel or nickel base material welded to carbon steel. Obviously whether PWHT will be required or not must be addressed elsewhere, such as in a company specification, fabrication drawings etc.
Typically it is not worth the trouble to combine PWHT and non-PWHT on a single WPS when the PQR’s differ in essential variables and/or supplementary essential variables.
In this particular case, the three PQR’s cannot be combined as the test plate with E6010, (F#3), was only tested in the PWHT’ed condition while the E7018 was tested in the PWHT’ed and as welded condition.
I am confused about whether impact testing is required or not. In your opening statement, you say impact testing is not required then in your question #3 you ask what thickness range would be qualified with impact testing required. The former, w/o impact testing is straight forward from QW-451.1; 1.5mm to 20mm. The latter is addressed by QW-403.6 for the minimum thickness and QW-451.1 for the maximum thickness; T to 2T or 10mm to 20mm.
Question 4 – Yes they may be combined on a single WPS, see QW-200.4
Question 5 – A WPS may be written for welding when impact testing is not required, based on a PQR with impact testing, by not addressing supplementary essential variables. All other essential variables, including PWHT, must be addressed per Code.
Question 6 – The proposed WPS is not valid due to the issue with E6010 as discussed above. With impacts required, the combining of PQRs 1 and 3 would be potentially possible but only for P1G1 to P1G1. When impacts are not required, any P1 to P1 weld would be qualified as G-number is not required and only P# is invoked as an essential variable, QW-403.11. QW-403.5, G-no., is a supplementary essential variable and therefore is required only when impacts are required; see QW-403.5 for an explanation or clarification.
John
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of asad azmi
Sent: Saturday, August 07, 2010 3:29 AM
To: materials-welding@googlegroups.com
Subject: [MW:6355] query regarding ASME SEC IX
Dear All,
Greetings.
I have to reveiw a WPS which involved welding by SMAW process. WPS has two filler metals E6010 and E7018 mentioned seprately in filler metal section(QW-404).WPS dont require any impact testing. WPS has note - this WPS is qualified with and without PWHT.
three PQR are supporting the above WPS. Detailed as below.
1) PQR is welded by using base metal, P1G1 TO P1G1(SA 516 GR 60 TO SA 516 GR60) . filler metal used is E7018. Thickness of base metal used for PQR Qualification is 10 mm. impact testing is done for this PQR.
2) ) PQR is welded by using base metal, P1G1 TO P1G1(SA 516 GR 60 TO SA 516 GR60) . filler metal used is E6010. Thickness of base metal used for PQR Qualification is 10 mm. impact testing is done for this PQR. Also PWHT is carried out at 1150 deg. F for 6 hours.
3) PQR is welded by using base metal, P1G1 TO P1G2(SA 516 GR 60 TO SA 516 GR60) . filler metal used is E7018. Thickness of base metal used for PQR Qualification is 10 mm. impact testing is done for this PQR. Also PWHT is carried out at 1150 deg. F for 8 hours.
my question is
1) whether the above WPS can be accepted based on the 3 supporting PQR'S.
2) Whether A SINGLE WPS can be qualified with and without PWHT by supporting PQR'S with and without PWHT.
3) What will be the thickness range qualified based on the actual thickness of base metals used in PQR Qualification. i think qualified base metal thinkness range will be 10 to 20mm as impact testing is done.
4) whether two diffrent filler metals such as E6010 and E7018 can be mentioned on single WPS.
5) Whether WPS without impact testing and PWHT can be qualified with PQR having impact testing and PWHT.
6) Whether the above WPS can be used for welding any ASME P1G1 Material together or to an ASME P1G2 material as required.
Awaiting your valuable reply.
Thanks in advance.
Regards
Asad Azmi
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