Inconel FCAW

By pipewelder_1999 (****)

Date 09-06-2001 11:26

I have no experience with FCAW Inconel but I have used FCAW solid wire with nickel alloys with pulse arc in all positions and it worked quite well.

I have seen the finished product on a garbage burner in Nashville that was done downhill with solid wire. (It really cost me alot of of overtime money )

There is a company called "Welding Services" I think that does this type of work.

Performing a test using the parameters you want to use and cutting a cross section and etching may give the customer a little more confidence in you selecting your own welding parameters.

Are the floor tubes cracked and you are going to clad over them? THe BLRB floors I have seen had many transverse cracks that usually extended the the CS core but stopped and were repaired in localized spots. Is the Inconel over SS something new thats being tried?

Sorry I can't be of more help

Gerald Austin
http://www.weldinginspectionsvcs.com

By dasimonds (**)

Date 09-06-2001 13:11

I'm under the impression that the reason for the cracks is the difference in coefficients of expansion, with stainless being almost twice that of carbon steel. We're told that Inconel and carbon steel are almost the same, as far as expansion coefficients go.
We would normally remove the crack, PT, repair , PT, and hydro, but in this case the old floor is going to be completely replaced with an inconel clad, carbon steel composite tube.
I believe the tubesheet manufacturers of became aware of the discrepancy a few years ago, and are now making new composite tubes using Inconel instead of Stainless.
Yes, this is a BLRB.
We do all of our own welding, as we are a maintence contractor, more or less, and service probably close to 40 power and recovery boilers, not to mention the other types of work we also do.
Dale Simonds

By M-Squared (**)

Date 09-06-2001 12:53

There is also a company called Riggs Distler who performs this type of welding. When I was working in a steel mill, they performed 625 cladding to one of our BOF hoods. Slick process, they did the hood in 7 days.

The key here is to use either a pulse machine or a Synergic pulse welding machine and weld in the vertical down position. By using the pulse machine and welding vertical down your heat input will be minimized. This will help with distortion and limit the amount of dilution of the weld metal.

After Riggs performed their weld overlay on the first BOF hood, we decided to do what is call the slope (basically tube to membrane). I rented welding machines from miller (which they called Synergic, but they were not) and proceeded to write and qualify welding procedure and welders. The process took one month and we did notice a difference with different wires. Memory escapes me as to the brands we tried and what we actually used, but beware there is a difference. This procedure was for hand welding and once the parameters were set the welders did not have any problems hand welding. The beads were uniform and looked good. I was in the process of qualifying a procedure using the Bug-O but left the company.

I believe that the pulse system is the way to go for either hand welding or Bug-O welding using vertical down welding. Bead sequence is important. Riggs was able to achieve a bead width of 11/16 with the system they were using (very much like a bug-o).

By dasimonds (**)

Date 09-06-2001 13:39

The only pulse equipment we own is an aluminiun wirefeed rig that runs like it has a bad liner( the wire pulses, with no power source modulation).
The required membrane weld is a 1 pass seal weld, both sides, and in the verticle up position. We seem to deal with a lot of customers who are seemingly narrow minded, or unwilling to change, relying heavily on "thats how we've always done it". Not to mention the fact that's it's taken me nearly 10 years to get my employer to buy FCAW wire larger than .045".
I hope you can see a little of what we're dealing with.
Thanks for the good ideas, but at this time, for us, they don't seem particularly feasible, as we start the shutdown Saturday, just 2 days from now.
Dale Simonds

By RonG

Date 09-06-2001 17:14

For what its worth, We bought an ESAB DIGI pulse machine a couple years ago and have really had good results with it. We bought 2 more.

Never tried FCAW in the pulse mode (we run Inco solid wire) but it is great in all position for any alloy and very quick and simple to set up.

Also they have water cooled torches that helps alot.

By pipewelder_1999 (****)

Date 09-06-2001 18:23

I agree with the pulse. I have made better looking vertical up welds than any flat SMAW welds with Inco.

By dasimonds (**)

Date 09-06-2001 21:02

pipewelder_1999 and RonG,
I personally ran a lot of GMAW-P back when I worked in a shipyard, during the 1980's. E70s-2, 100s-1, etc..., depending on the application. I thought it was an excellent tool, but suseptable to LOF, much more so than say, FCAW. The machines we used were , in my opinion, quite complicated. But that was 12 years ago. I believe the shipyard has drastically reduced the use of GMAW-P, because of the LOF issues. Staying on the leading edge of the weld pool in a test booth is one thing, cramped up in a compartment the size of a dog house is quite another. I personally air arced several horizontal seams because of LOF to the lower bevel.
But as I stated earlier, I think GMAW-P is an excellent welding tool and skill for one to keep in his bag of tricks. And it would in all actuality, probably be the best solution in this case. However, I'm probably the only welder in my company that has run true GMAW-P. I'm sure we don't even have a procedure for GMAW-P. How do you train 50 welders, in 2 days, to compentantly weld GMAW-P, with no experience, with an Inconel solid wire no less (I'm assuming Inconel solid wire might be more difficult to weld than say E70s-2 in pulse mode, but I have never welded with it, so I'm guessing). No welding engineers from which we can draw information. We don't have any machines capable of pulse arc. All we have are Lincoln LN-25's, and mainly utilized with a constant current power supply. Good feeders. But are they capable of pulse arc? I don't know. We used Gilliand pulse arc feeders at the shipyard. They only differed in that the feeder had a vernier control(secondary, or rather, fine tuning wire speed control). You see why I stated earlier I thought it was not feasible at this time.
Actually gentlemen, I'm just a welder on this job. I'm probably going to be the guy that has to do the welding with the bug-o on the night shift. We only have 1 machine capable of both weaving and dwelling. The Avesta FCAW 625 .045 wire is what I'm going to have to weld with. I'm just trying to hedge my bets. I'm not sure of the parameters of the wire. One of our boiler engineers told us to set the machine at 33 volts. No wire feed speeds. No travel speeds. No dwell or oscilllation settings. Just 33 volts. I wonder if he didn't pull "33 volts" from where he sits. I got more information from the welding salesman.
Thank you both for your input.
Dale Simonds

By pipewelder_1999 (****)

Date 09-06-2001 21:47

I've been involved in a few of the recovery boiler floor/wall repairs too and I hope it all works out for you.

Those shutdowns in the recovery boilers always have something exciting.

Your probably correct about the 33 volts!

By RonG

Date 09-07-2001 12:06

I hear you !

At one time GMAW was out-lawed in our shop because of LOF but since the Inverter has come around the biggest problem we have is LOT (Lack of Talent)

By dasimonds (**)

Date 09-07-2001 15:24

As I remember, a lot of the other welders fell in love with the process. I personally thought it had a lot of uses, such as the ability to seal a 1/2" gap, vertical down, 1 pass, and completely acceptable to the navy. We were in mid-process of working out the bugs in the equipment, when the Brittish had their incident in the Falkland Islands. If you remember, they took a missile (I forget who sent it to them) right smack into the deckhouse (the aluminum superstructure above the main deck) on one of their ships. Apparently, it started some kind of reaction, and the aluminum started burning. Thereafter, the U.S. Navy scraped the aluminum superstructure. As far as I know, the superstructure is now made of HSLA-80, 5/32" thick. AS .052" FCAW is a bit heavy duty for this thickness base metal, GMAW-P found its new home in the shipyard. Perfect place for it. Ideal for distortion control. It had already proven its usefulness when we were still doing the aluminum deckhouses. While the majority of the aluminum was around 3/8" in thickness, focal areas for stress required aluminum several inches thick in some places. As GMAW aluminum has some of its own LOF issues, GTAW was usually employed to weld these areas. But as we know, GTAW aluminum requires AC current, and a continuous high frequency unit. This sometimes led to a flaking of the tungsten electrode, which would show up on RT examination, leading to costly repairs. Here comes GMAW-P to the rescue. It performed flawlessly, once the welders figured out what to watch for.
I deal with a lot of LOT. Actually, I think it sometimes relates to experience level. What troubles me more than LOT is LOC (Lack of Caring). "Close enough" . Thats bad enough from the new welders just starting out. I always give them a good chiding, and go on my way. But what really disturbes me it when I get the same "close enough" attitude from the engineers and foreman. While it is true that everything doesn't have to be perfect to make an acceptable weld, what part of the process can you omit and still get a quality weld the customer will accept? The prep? The alignment of the ID's? The preheat? Interpass cleaning? In process defect removal ( a bad start maybe)? Spatter on the OD? Arc strikes? PWHT? I could talk for a week about preping alone. I've never been on a job where the ID of the fittings ( 90's, 45's etc...) matched the ID of the pipe. I remember 1 case in particular, because it was so outlandish, and just happened last year. We were working on some 22" diameter P-22 chrome, 1" wall thickness, 100% RT. My fitter said he was ready for a tack weld. I asked him how it looked. He said "Beautiful!". He was lying. There was 1/2" ID difference, all on the top half of the joint!. I told him he would have to counterbore the fitting ( a 90 ) so the ID's would match more closely. He looked at me like I was crazy, shouting "that's a lot of work" . I told him I knew that, and if this work was too hard for him, maybe he should seek employment in either the food service or housekeeping industries.
Dale Simonds

By rodofgod (**)

Date 10-21-2003 21:58

Just a quick 'pick-up',the superstructure of the previously mentioned ship (H.M.S. Sheffield) was infact made of a Magnesium alloy not aluminum! The warhead didn't denotate but the resultant fire from the propellant 'ignited' the magnesium alloy and caused the eventual loss of the ship!

Anyone remember that experiment with Mg and water from high school???

By dasimonds (**)

Date 09-07-2001 15:36

Oh yeah. The shipyard welding engineers said FCAW-P was a definite no-no

By RonG

Date 09-07-2001 17:18

LOC! What an apt discription, "Yea thats close enough for Government work"

Thanks for that "LOC". We have a document in our ISO manual that all our WPS reference called "Welding Principles" I will update it and make use of LOC if you don't mind being plagiarized.

By dasimonds (**)

Date 09-07-2001 20:38

Go for it!

By brande

Date 10-26-2003 04:49

On many conventional pulse units, running FCAW will tend to trap slag and can cause wormhole porosity. The relatively fast freezing puddle might be the culprit.

Good Luck

brande

By dasimonds (**)

Date 10-04-2001 20:06

I'd like to thank everyone for their comments and suggestions.
We never utilized the bug-o during the entire job. The dayshift foreman thought it would be faster to weld the membrane with the Inco 112 SMAW electrodes in the flat position. The vertical membrane were also welded with the Inco 112, as the fit-up was too inconsistent for the bug-o ( root opening ).
I must say that I'm impressed with the excellent job our team did with the Inco 112 electrodes.
We also finished with a 1.7% rejection rate on 368 RT welds.
On a much sadder note, one of our top people was killed during the shutdown. He was electrocuted while working in an MCC room with a plant electrician. The plant electrician left the room to get some parts, returning to find Jim unconsious. They theorize he was kneeling in a puddle of water, and contacted 110 volts on his forearm.
He will be missed.
Dale Simonds

By rbrxsmsglobal Date 10-06-2003 17:46

Very sorry to hear about the loss of your talent. Our condolences to you and the Family of Jim.

The next time you have welding issues using robotic equipment, we would like to offer our assistance to you. As specialists in welding with automatic equipment and Nickel based materials, we could have solved your issue. But happy to read the project was a completely satisfactory with the alternative. I found this thread only yesterday and I read with great interest. You had stated to have work in a shipyard and with the Gilliland Power supply, was that yard EB in Groton?

all the best

By ssbn727 (*****)

Date 10-06-2003 22:02

Hello rbrxsmsglobal!!!
Welcome to the forum!!!
I worked at EB for a few years back in the late 70's - early 80's...
I have to say that I do'nt recall the Gilliland power sources that were mentioned... Perhaps, because it was so long ago... but, I do'nt recall the equipment they were using... Well - I must be getting old!!!
I was wondering if you could explain a little more about these power sources if possible... I do remember that some of the submarine hull sections were welded together using a combination of welding processes that included capping some of the joints with GMAW-P back then...
When I was employed at EB in "Rotten Groton, CT"... We welded with alot of nickel-copper (Ni-Cu), copper-nickel (Cu-Ni), and a variety of inconel, hastelloy,etc. alloys, and of course a whole bunch of different other alloys... Most of the welding was done using the GTAW process although, there was on occasion, some SMAW performed with these nickel based alloys... If you were there also, I would like to talk about some of the "unclassified" experiences you had there...
I spent alot of time in the two bars across the street from each other on Eastern Point Road, and as a trick question, do you remember the name of those two bars? I ask you this because, anyone that spent some time at EB would never forget the names of these two establishments, especially when all of the fun that happened when the bars closed at what time on fridays???... Also, three last questions would be: What was the name of the yard that had the Welding school, and where was the Pipefitters local hall, and their local number designation???
look foward to reading more from you soon!!!

Respectfully,

SSBN 727 Run Silent... Run Deep!!!

By dasimonds (**)

Date 10-07-2003 12:13

It was at Bath Iron Works in Bath, Maine. As I remember, all the power supplys used for GMAW, GMAW-P and FCAW were Gilliand(spelling?).

Dale Simonds

By ssbn727 (*****)

Date 10-07-2003 12:46

Hello Dale!!!
The Falklands incident you mentioned was between the British and the Argentinians...
The missile was a French made "Exocet" launched from a French made "Super Enternard" land based jet fighter...

I was wondering who made those Gilliland or Gilliand welding power sources? TIA...

Respectfully,

SSBN727 Run Silent... Run Deep!!!

By dasimonds (**)

Date 10-07-2003 18:29

Hi SSBN 727,

I just did a search and came up with Malcolm T. Gilliland welding machines. You can check it out at http://www.mtgilliland.com.

The pictures on the web site won't load on my computer, just a box with a red x in it, so I can't be certain. But with such an odd name, I'd bet it's the correct web site.

Hope this helps

Dale Simonds

By ssbn727 (*****)

Date 10-08-2003 04:42

Hi Dale,

You're right about the pics... The website has some errors in it, and it's probably why we ca'nt see the pics...

Thanks for the info anyway!

Respectfully,

SSBN727 Run Silent... Run Deep!!!

By dasimonds (**)

Date 10-08-2003 13:23

Did you check out the battery powered spool guns? 75' of 1/4" weld.

Great thing if you drive a beater vehicle and have to stop on the side of the road and weld the frame!!!!!!!!

Dale Simonds

By ssbn727 (*****)

Date 10-08-2003 19:45

Hi Dale,

Do you think the welds will hold? I have'nt had the opportunity to try out one of those yet but, if it really works then, why not have one of those in the trunk... I wonder what it'll do to the PCM in the beater???

Respectfully,

SSBN727 Run Silent... Run Deep!!!