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Multi Process Welding Procedures QW200.4 and QW451.1

Base Metal approval range for the above welded joint is 4.76mm To 52mm Ref QW451.1

If the joint is made of more than one welding process then the maximum deposited thickness each

process in the above example is (2 x Deposited Weld Metal t) :- GTAW 12mm and SMAW 52mm

(This is because t = T for this process as t > 19.1mm QW451.1)

If the SMAW deposit in the above qualification was less than 19.1mm, assume 18mm and GTAW

8mm then to weld a joint 52mm thick with 8mm GTAW and 44mm SMAW is not permitted as

maximum SMAW deposit would be 36mm

You can delete the SMAW and qualify an all GTAW weld 4.76mm To 12mm thick or delete the

GTAW and weld SMAW 4.76mm to 52mm thick, providing all the essential, non essential and

supplementary variables are applied to the WPS. (Note the procedure allows the SMAW to be used as

a root run but not the welder qualification.)

When tested the deposited weld metal of each process must be included in the tension and bend test

specimens and impacts where applicable. Note it is acceptable for the impact test for the GTAW to

contain some SMAW in the test specimen.

PICK and MIX QW200.4 b [Note restrictions in QW451.1 notes (1)]

This applies to test coupons 13mm and thicker and welding processes SMAW, SAW, GTAW, GMAW.

A WPS consisting of several processes can be created from different PQRs, but the maximum

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thickness of base metal covered by this WPS cant exceed 2 x the thickness of the thinnest test coupon

used for each PQR and each process cant exceed 2 x its deposited thickness. This applies even if all

the processes used for that coupon are not required in this WPS. However the base metal thickness of

the PQR used for the root does not have to be considered if the WPS is single sided QW200.4 b

Note test coupons 38mm and above approve deposited weld metal and also base metal thickness up to

200mm max QW451.1. (QW403.7 Processe GTAW,SMAW,GMAW,SAW)

EXAMPLE

Can the proposed PQR be made from the above example + PQR 2 + PQR 3.

Consider individual deposited thickness 2 x t

GTAW 12mm > 6mm. SMAW 60mm > 39mm. GMAW 66mm > 20mm All OK

Consider Plate thickness 2 x T

SMAW 60mm 65mm OK. GTAW not considered.

SMAW procedure cant be used for proposed PQR

WELDER PERFORMANCE QUALIFICATIONS

If you want to weld a 30mm plate and your welder qualifications only go up to 15mm use two welders.

You cant use one welder with two different qualifications for the same process