GMAW or FCAW

By pipewelder_1999 (****)

Date 04-01-2001 12:14

It is FCAW.

By overthehill (*)

Date 04-01-2001 16:12

Thanks. Not quite the same subject, but I've got question about
Innersheild (flux core without a purge). In the last 15 years I have only seen this used on 3 jobs. One was totally unsuccessful, and the other two, I didn't care for it that much. I could have done a better job with 7018 and 7024. Currently, there seems to be a strong marketing effort for consumers (ie. 110 v input/ 20% duty cycle welding machines) and my favorite welding supply people tell me the wire itself is not recommended for metals over 5/16 in. Is anybody in the welding industry using this stuff?

By pipewelder_1999 (****)

Date 04-01-2001 18:21

I have used it in the manufacture of industrial and commercial fan impellers up to 120" in diameter. I have found that almost anything than runs on a machine you can plug into your wall outlet may not perform as well as it would on a industrial/commercial machine.

Self shielded Flux Core wires do not lend themselves to mixing with other weld metal types. Its chemically related. If you were welding over existing weld metal then it's not a suprise you had problems.

Another factor that may make some people not like it is in some cases with E71T11 thay don't bother to read the instructions and change the polarity on the power source. It runs on DCSP (Electrode Negative).

The wire that I was involved with (5/64" E71T11) would make sound welds on with a deposited weld metal thickness up to 1/2" if I remember correctly. The thickness limitation is required because some of the chemicals in the wire could accumulate in the weld. The bigger the wire diameter the greater the thickness limitation. You may want to ask your steel supplier if the thickness of the base metal is limited or the deposited weld thickness.

Lincoln Electric has much information on Innershield since that is their Trade Name.

As with all processes and procedures they all have their place. Also anybody can show or tell you how something doesn't work well it takes differnt types of desires to prove something works compared to proving it doesn't.My wife can show you that 1/8"E7018 will not run uphill.

Innershield has been produce by Lincoln Electric for years and I don't know its popularity but if I had to have only one wire for using around the house on carbon steel, Innershield (NR211MP) would be the stuff. No Nozzles, No wind problems, great variation in stickout, makes deep penetrating welds downhill (Designed to) and it kinda reminds me of a never-ending 6011.

Another feature with Innershield that you dont have with gas shielded wires is the ability to weld with say 2"-3" inches or more of wire stickout. This allows for changing the characteristics of the puddle without turning a single knob on the machine.

It has its place. Have you ever run a gas shielded gun in a 20 MPH wind? The gun and cables are much lighter and flexible than an equivelent rated gas shielded gun.

I hope you have a nice day. Your questions may get more informative answers if posted in the "Shop Talk" or "Technical" sections. But regardless of the location pleas post them.

Gerald Austin
http://www.geocities.com/pipewelder_1999/

By overthehill (*)

Date 04-02-2001 04:48

Pipewelder,

I think I'll take your advice and move this to shop talk. While I try not to let it show, I am just a dumb redneck welder. Actually, I learned the trade in ASME pressure vessal shops during the late 70's in Odessa, TX.
I was an non union ASME certified pipe welder (mainly tig stainless) working refinery and petrochemical plant construction until my suitcase wore out about 5 yrs ago. The last couple of years I have been giving free welding clinics for farmers, loggers, local industries, and also to high schools students. When dealing with non-professional welders, you get a wide variety of questions. While I know a little about SMAW, and use GMAW or FCAW-GS nearly every day in my shop, I have limited experience with FCAW-SS. The only people who seem to be using it with in a 100 miles of where I live are consumers (using the inexpensive little machines) who don't want to buy sheilding gas. I was just interested if this process is really being used in the industry, especially since the seismic business. I'll ask around, thanks.

By pipewelder_1999 (****)

Date 04-02-2001 16:48

I wish I could teach too. Any questions you have will be gladly answered if possible. I figure the only way I will ever use the little bit of stuff I know about welding is to share it with someone else.

have a good day

By fbrieden (***)

Date 04-02-2001 18:28

Sir,

I beleive you are incorrect in stating that "1/8 E-7018 will not run up hill".

Francis X. Brieden
Welding Department Chairman
Johnson Technical Institute
3427 North Main Avenue
Scranton, PA 18508
fbrieden@netscape.net

By pipewelder_1999 (****)

Date 04-02-2001 21:41

I know.

I have however seen welders that could not or would not weld a 6" carbon pipe together with 1/8" 7018 and had to use 3/32".

I was stressing the fact that sometimes people will say something won't work as opposed to saying that they themselves do not have the skills or knowledge or work ethic to perform a given task with the most efficient method or procedure.There are welders that I sometimes work with that are confident that you cannot put a B31.1 acceptable root in a piece of pipe with 6010. All they have ever done is tig weld. There are others that don't think you can put a code (ASME SEC I) root in a boiler tube with E-7018, but it has been done.

NOTE > My wife has never welded. :)

Have a pleasant day and then share it.

Gerald Austin

By fbrieden (***)

Date 04-03-2001 03:16

Dual shield is a FCAW process. The inner core flux of the tubular electrode is supplemented by an external shielding medium. This shielding "gas" is an external application and should not be implied as a purge. The proper designation of this process is: FCAW-G

Francis X. Brieden
Welding Department Chairman
Johnson Technical Institute
3427 North Main Avenue
Scranton, PA 18508
email: fbrieden@netscape.net