Couldn't get better answer than this, thanks a lot.., this is the reason i love this forum.
Also thanks to Pravin and Raghuram for their valuable information,
Regards
Manpreet Singh
On Wed, 29 Dec 2010 23:25:51 +0530 "John Henning"
>
QW-200.4 (a) allows you to combine these two PQR's to support a single WPS. In such a case the WPS will be restricted to the minimum range qualified by the PQR base metals (per QW-451); i.e. the intersection of the two individual qualified ranges. Therefore, your WPS would allow the following (assuming no impact requirements):
Qualified base metal range: 5mm to 12mm ( 1.5mm < T1 < 12mm, 5mm < T2 < 30mm )
Maximum Qualified GTAW deposit: 12mm
Maximum qualified SMAW deposit: 12mm
REF: (from HSB site) Interpretations – File No. BC-80-628, no interpretation number
Question (2): A WPS is being written for groove welding of pipe to utilize a GTAW root pass and SMAW fill. A previously qualified PQR welded on a ¼ in. thick test plate using GTAW and a previously qualified PQR welded on a 3/8 in. thick test plate using SMAW are to be used to support the combination WPS. What are the maximum thickness ranges of the combination WPS?
>
>Reply (2): Based on Question (2), the deposited weld metal thickness range for the GTAW is 1/16 in. through ½ in. and for the SMAW is 1/16 in. through ¾ in. The base metal thickness range for the combination WPS is 1/16 in. through ½ in.
Ref. also, HSB topic Specific Code FAQs:
| Q: Is it possible to apply two separately qualified WPS's to the same joint in combination without qualification of a combined PQR? |
| A: Per QW-200.4, it is acceptable to apply both WPS's to the same joint without further qualification. The deposited weld metal qualification ranges may be "stacked", allowing the application of the maximum qualified thickness of deposited weld metal for each WPS/process in a single joint. However, the user is cautioned that the maximum base metal thickness qualified for the most limiting WPS must be applied. The base metal thickness ranges cannot be "stacked" to qualify for a greater thickness in combination. (In my opinion the italicized section also applies to the minimum qualified thickness as well as the maximum) |
If impacts were required, since there would be no intersection of qualified base metal thickness, one could not combine the two PQR's to support a valid WPS. New PQR(s) would have to be performed.
QW-200.4(b) is an exception to the general rules for root pass process qualified with a PQR with base metal thickness > 13mm, and a second PQR for a fill process qualified with a base metal thickness greater than the base metal thickness used with the root pass PQR. With the enquirers conditions, QW-200.4(b) does not apply as both PQRs would have to have been performed on material thickness greater than 13mm which is not the case. One example of an acceptable combination would be PQR 1 –13mm thick base metal w/ GTAW root (for the purpose of example say 6mm deposit thickness, t) combined with PQR 2: 38mm base metal thickness welded completely by SAW
These conditions would result in a combined WPS such as:
Qualified base metal range: 5mm to 200mm
Qualified maximum GTAW deposit thickness: 12mm
Qualified maximum SAW deposit thickness: 200mm
Hope this helps - John
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of praveen alavandar
>Sent: Wednesday, December 29, 2010 5:35 AM
>To: materials-welding@googlegroups.com
>Subject: Re: [MW:8984] Combination of PQR for WPS
| manpreet, you still cannot combine both these PQRs, you should either use PQR 1 or PQR 2. Regards, Praveen
|
--
>To post to this group, send email to materials-welding@googlegroups.com
>To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com
>For more options, visit this group's bolg at http://materials-welding.blogspot.com/
>The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
>To post to this group, send email to materials-welding@googlegroups.com
>To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com
>For more options, visit this group's bolg at http://materials-welding.blogspot.com/
>The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
>
-- To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
No comments:
Post a Comment