[MW:4116] FW: 4106] essentials about SAW PROCESS

 

Mr Asghari,

 

Both QW-404.10 & 404.27 applies to procedure qualification by SAW and are essential variables. In SAW , one can do the alloying through flux only, or though wire or through flux and wire combined.

 

You may be aware that SAW fluxes are manufactured (briefly without going into details) as acidic flux, basic (agglomerated, bonded or fused) or neutral fluxes. Each flux behaves differently during welding. Due to these factors SAW flux is so important and fabricator has to know precisely the AWS classification as mentioned in SFA -5.23 or SFA 5.17 as provided by consumable manufacturer.

 

QW 404.10-  Where the alloy content of the weld metal is very much  dependent upon the composition of the flux used, any change in any part of the welding procedure may result in the important alloying elements in the weld metal being outside of the specification range  given in the Welding Procedure Specification. If  the production welds are not being made in accordance with the procedure specification, the authorized inspector may require that a check be made on the chemical composition of the weld metal on a production weld.

 

QW-404.27— Where the alloy content of the weld metal is largely dependent upon the composition of the supplemental filler metal  or any other form of additive, such as  alloy powder. This changes weld metal chemistry thus deemed as essential variable as per ASME Sec-IX.

 

Regarding your earlier queries:-

 

·         what is effect of filler composition in transfer mode in GMAW?—None, transfer mode is a function of, wire size, shielding gas and Polarity/ Arc Current.

 

·         why backing material is required for FCAW for root pass?—FCAW is not meant to be a full penetration weld , unless some improved and special  power source is used, such as STT.

 

 

Hope I have tried to clear your doubts. I am attaching an e-book on SAW for your reference.

 

Thanks

 

 

Pradip Goswami,P.Eng ,IWE 

Senior Engineer/Specialist(Welding-Metallurgy)

Machine Dynamics & Component Integrity Dept.

Engineering & Training Services Division

ONTARIO POWER GENERATION Inc.

PO Box-2000, RR-55(South)

Nanticoke, Ontario,N0A1L0

Tel:-(519) 587-2201, Ext 3107--in Nanticoke

         (416) 231-4111, Ext 5925--in Kipling,Toronto

Fax: (519) 587-6814

Email-pradip.goswami@opg.com.

 

 

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of ali asghari
Sent: Wednesday, January 20, 2010 5:35 AM
To: materials-welding@googlegroups.com
Subject: [MW:4106] essentials about SAW PROCESS

Dear all

does anybody have experiences or interpretations about

QW 404.10 & 404.27(the alloy content of the weld metal is largely dependent(how can assess) upon the composition of the flux used, any change in any part of the welding procedure which would result in the important alloying elements in the weld)

 

QW 404.24:10% VOLUME IN TOTAL LENTGH OR NOT?

 

 

1

 

 

REGARD ADVANCES.

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