Materials & Welding: Re: [MW:13106] QW-200.4

Wednesday, November 30, 2011

Re: [MW:13106] QW-200.4

Hi Aly,

Below is interpretation based on Mr. John's wonderful explanation to me in this forum:-

Aly's interpretation is correct based on QW-200.4 (b) but if base metal thickness are lesser than 13mm, QW-200.4 (b) does not apply and below would be the answer:-

PQR 1- 1.5mm to 12mm

PQR 2- 5mm to 30mm

Qualified base metal range: 5mm to 12mm ( 1.5mm < T1 < 12mm, 5mm <

T2 < 30mm )

Maximum Qualified GTAW deposit: 12mm

Maximum qualified SMAW deposit: 12mm

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.

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.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, please let me know if in doubt.

Regards

Manpreet Singh

From: "Aly" <mhaskar.aly@gmail.com>
Sent: Tue, 29 Nov 2011 16:10:03
To: <materials-welding@googlegroups.com>
Subject: Re: [MW:13071] QW-200.4

Advantage of combining two processes:

Suppose u have two wps as below

1: WPS with GTAW with 13mm base plate thickness (Base metal Qualification range is 26mm max)

2:WPS with SMAW with 20mm base plate thickness (Base metal Qualification range is 40mm max)

If u combined these two WPS, the advantage you can get is u can weld GTAW process double the max thickness between two process ie (2 x 20mm = 40mm) not upto 26mm only.

You can use more than one WPS in one single joint, just to increase base metal thickness qualification range one can combine two process as per QW-200.4(b).

You can create many WPS from one single PQR as needed.

Hope this is clear for you..

Mhaskar Aly

-------Original Message-------

From: sevak hiren

Date: 18/11/2011 21:08:13

To: materials-welding@googlegroups.com

Subject: [MW:13020] QW-200.4

Dear experts....Can anyone provide some Section IX interpretations for clause no.QW-200.4 ?................Can anybody explain this clause better ?...........It clearly states that multiple wps of different processes can be combined together and we can make a single wps combining that processes...........and from one pqr combining different processes ,individual wps can be prepared for each process..............the root deposites clause of min 13 mm is an ALTERNATE requirement....is it really applicable in which situation ?...............

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