compressors with flux core every day. Most of our subcontractors use
it exclusively for the structural components such as the skids. It is
an excellent process, but does require more skill than the average
process. It has received a bad name due to BOTH quality issues many
years ago AND lack of skilled welders using the process. There are
rarely quality issues with the product. There are still issues with
welders not able to run the process correctly. We benfit since most
of the welders here have 20-30 years running the process and we have
used the same brand and wire for the past 10-15 years.
Biggest issue is that welders try to weld FCAW the same way as GMAW.
You drag with FCAW and push with GMAW. If you push with flux core,
you risk getting slag inclusions and other problems. Also a 200F
preheat is always best with FCAW. Not all brands of FCAW run the same
so it is necessary to buy different brands and let the welders use
them and see which one runs best.
There are still a few clients that have FCAW restrictions in their
specs. We present them with our years of experience and excellent
track record with the FCAW process and they always allow us to use it.
On Feb 21, 10:43 pm, "Bathula Raghuram (Mumbai - PIPING)"
<R.Bath...@ticb.com> wrote:
> please refer QW 255, Gas metal arc welding includes both GMAW and FCAW.
>
> ________________________________
>
> From: materials-welding@googlegroups.com
> [mailto:materials-welding@googlegroups.com] On Behalf Of Soliman,
> Mohamed (kuwait)
> Sent: Sunday, February 21, 2010 12:29 PM
> To: materials-welding@googlegroups.com
> Subject: RE: [MW:4355] MW:[4348] FCAW Process - Pressure Vessel
>
> Hi ,
>
> It is not recommended to use FCAW process for the welding of the
> pressure components .You can use it only for the saddles and other non
> pressure parts.
>
> Thanks
> Best Regards
>
> Mohamed Soliman.
>
> QC / QA Engineer.
>
> Mob.: +965- 6578- 3286
>
> BS-160 , SEK <mailto:Mohamed.Soli...@worleyparsons.com>
>
> ________________________________
>
> From: materials-welding@googlegroups.com
> [materials-welding@googlegroups.com] On Behalf Of pgoswami
> [pgosw...@quickclic.net]
> Sent: Sunday, February 21, 2010 7:35 AM
> To: materials-welding@googlegroups.com
> Subject: [MW:4352] MW:[4348] FCAW Process - Pressure Vessel
>
> Dear DST,
>
> FCAW is an accepted welding process for construction of pressure
> vessels, designed as per ASME Sec-VIII,DIV-1. This was accepted as as a
> code interpretation query:-
>
> *
> Interpretation No- VIII-1-86-81
> *
> Date of Issue:- Aug 27,1986
> *
> File :- BC86-334
>
> If you need to get hold of this code interpretation, you may write to
> ASME. If you have access to NACE or One petro you may get hold of this
> paper, which gives a a detailed history and analysis of various FCAW
> problems.
>
> Hope it would help you.
>
> Thanks.
>
> Pradip Goswami,P.Eng.
> Welding & Metallurgical Engineer/Specialist
> Component Integrity Section.
> Engineering and Training Services
> Ontario Power Generation Inc.
> Res:-88,Garth Trails Crescent
> Hamilton,Ontario, L9B2X1,Canada
> Email-pgosw...@sympatico.ca
> Email-pgosw...@quickclic.net
> Tel-905-679-9677
>
> Paper Number 08553
> Title Flux-Core Welding in Refinery Service
> Authors Richard L Colwell, Bechtel Corporation; William Layo, Midalloy
> Source CORROSION 2008, March 16 - 20, 2008 , New Orleans LA
> Copyright 2008. NACE International
> Keywords Flux-Core Arc Welding(FCAW), semi-automated,
> consumables, refinery, wire, shielding gas, enviromental cracking, wet
> H2S, pressure vessel, hear exchanger, piping , fabrication
> Language English
> Preview ABSTRACT
>
> While its reputation has been stigmatized by early quality problems in
> the 1980?s, Flux-Core Arc Welding (FCAW) has evolved into a process by
> which experienced fabricators can obtain radiographic quality welds in
> many alloy systems. Research and development, modern manufacturing
> techniques, and improvement in sensor and inspection technologies have
> produced consumables for gas-shielded procedures that can meet many
> petroleum refinery industry specifications. During the last decade there
> has been increased pressure exerted by fabricators on buyers to utilize
> Flux-Core Arc Welding (FCAW) where possible, today?s competitive market
> has enabled fabricators to persuade segments of the power, chemical, and
> petroleum processing industry to accept FCAW for pressure vessel, heat
> exchanger, and piping fabrication applications in order to reduce both
> cost and schedule. Even though many refinery owner/operators?
> specifications prohibit the use of the FCAW for radiograph quality
> welds, there has been a growing trend to rethink the restriction, and
> allow the controlled use of FCAW (gas shielded) for petroleum refinery
> pressure retaining welds. This paper discusses the author?s experiences
> with the increasing use and ongoing limitation of FCAW(G).
>
> INTRODUCTION
>
> Flux-Core Arc Welding (FCAW) is a variation of the Gas Metal Arc Welding
> (GMAW) process, and is generically considered a "semi-automatic"
> process. Like GMAW welding, consuming wire is fed into the molten weld
> pool at a controlled rate. Flux-Core arc welding can be further
> characterized as self-shielding FCAW(S) or gas shielded FCAW(G). FCAW(S)
> is commonly chosen in structural steel fabrication due to its advantage
> of providing high deposition rates. For the purpose of this discussion,
> as it relates to pressure boundary weldments of radiographic quality,
> only the gas shielded process, FCAW(G), will be discussed in any detail.
> Flux cored welding produces a protective slag covering that is easily
> removed when correct welding parameters are followed. Flux cored welding
> has good bead appearance (smooth, uniform welds having good contour). It
> has been reported that 1957 saw the debut of the flux-cored arc welding
> process. This new process promoted the use of self-shielded coiled wire
> electrode that could be used with existing semi-automatic equipment,
> increasing the efficiency of welding fabrication projects. In FCAW(S)
> the electrode wire Is fed continuously to the work piece. This increases
> arc time and avoids stub losses typical of the shielded metal arc
> welding (SMAW) process. Another new wire, called an inside-outside
> electrode, had a tubular cross section with the fluxing agents in the
> annulus was also introduced at this time. The process was called
> Dualshield (r)1, was characterized by two modes of shielding gas;
> external gas and shielding gas created by the thermal breakdown of the
> annular fluxing agents. This process, invented by Bernard, was patented
> in 1957. Since that time the patent was acquired by a succession of
> companies, and is now owned by ESAB1. One thing to note is that these
> original dual shield wires were native to the USA, and for nearly 40
> years no foreign source could compare/ compete. Since then many other
> major supplier of FCAW(G) filler wires have entered the market.
> Number of Pages 16
> File Size 4346 KB
> Price US $ 10.00
>
> ________________________________
>
> From: materials-welding@googlegroups.com
> [mailto:materials-welding@googlegroups.com] On Behalf Of greetings
> Sent: Saturday, February 20, 2010 5:33 AM
> To: materials-welding@googlegroups.com
> Subject: [MW:4348] FCAW Process - Pressure Vessel
>
> Dear Friends,
> Can we use FCAW process in Pressure Vessels, Just I
> refered Sec 8 Div - 1(UW-27) which show all other process expect FCAW.
>
> Please Guide Me,
>
> Regards
> D.S.T
>
> Filtered by Hosted Filtering
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