INNERSHIELD Welding on Water Tank

By ssbn727 (*****)

Date 03-13-2006 06:12

Hi Randy!
Now, you did'nt mention what specific "innershield " wire electrode designation you're going to use, the diameter, etc. This info would help us in giving you some recommendations or suggestions. Remember some things about self shielding flux cored wire:
#1 Just because it's self shielded flux cored wire does'nt guarantee it from being impervious of the detrimental effects that windy conditions can cause so, shield the weld area if you're experiencing drafts that could effect the weld quality
#2 A self shielded exclusive FCAW gun w/accessories (contact tips, liners, drive rolls) should be used... I've seen some people use regular guns only to see them ruined in no time!!!
#3 You usually should use a longer wire stickout than what most of the gas shielded FCAW or GMAW electrodes require, but that depends on wire/electrode type, diameter & brand.
#4 Double check the proper polarity for the specific "innershield" wire being used.
#5 make sure the wire electrode designation can be used with the type welding equipment (CC vs CV power sources & voltage sensing wire feedrs or not) being used on the job.
#6 Make sure you use the proper heat input/voltage/amps settings in order to eliminate any possible slag incusions, lack of fusion, or any other discontinuities or defects.

That's all I can remember at this time and if I forgot something, there are other members that can give you some sound recommendations also so, get back to us with more details about the wire being used, and the type of welding equipment set up you're going to use on this job... Bottom line is, this company wants to complete this job ASAP and, with as large of a (profit) margin as possible...
Would'nt you if it was your business?;>)~ BTW, just out of curiousity, what does Whiteyford M1A1 represent as your call sign?

Respectfully,
SSBN727
Run Silent... Run Deep!!!

By whiteyford M1A1 (**)

Date 03-13-2006 13:42

Hi SSBN 727
Whiteyford has been my nickname since I was a kid, M1A1 I borrowed from the M1A1 Abrams Main Battle Tank. I worked at General Dynamics as a welder for about 3 years installing armor packages (welding).
The company elected to use ESAB Coreshield 11 .045 with a Miller SP32 feeder 300A innershield gun and Bobcat 225 source DC-. vertical welds are downhand
I would tend to disagree with your bottom line statement, time is a consideration on this job and every effort to maximize profit should be taken. But not at the expense of quality and earning a bad reputation to boot.
My concern lies with the fact that we are a new company that primarily does civil engineering and has never taken on a welding project before. We have a couple of laborers that claim to have been certified before and therefore qualified to determine welding applications. These guys personally guaranteed that the tank won't leak. I had planned on welding on it as well but withdrew because I could not make that same promise.
Thanks
Randy

By noplacetosail Date 03-13-2006 20:56

SSBN 727 is spot on in his assessment.

Coreshield 11 is an all-position self-shielded flux cored welding wire meeting all requirements for the E71T-11 classification.Coreshield 11 is excellent for use on single or multiple pass lap, fillet and butt welds on mild steels in all welding positions. Limitations do exist for multipass welds in excess of 3/8" (9.5 mm). It produces smooth arc action, full slag coverage, easy slag removal, and low spatter. This product should find excellent acceptance in general purpose mild steel fabrication. In structural fabrication, the product can be used where no seismic requirements are present. Coreshield 11 is run DCEN

.045 in, 225 Amp machine volts approx 18 140 ipm wire speed,
should yield approx. deposition rates of 356 cm/min 2.6 lbs./hr., 1.18 kg./hr. 82 % 1/2 inches, 12.7 mm

The vert down scares me a bit due to the fluxes generated by self shielded wires, I just attended a Lincoln FCAW training day put on by the person in charge of Lincoln FCAW and everything we did was vert. up ! Please check this out.

Please get ahold of your ESAB rep and have him swing by and work with your welders on the specifics of flux cored wires especially in relation to machine parameter settings and stickout ! No way would I trust dye pen on a tank when I could pressure test it instead ! Been there, seen that !

Good Luck
Don Murrell (cwi)
www.weldguru.com

By ssbn727 (*****)

Date 03-14-2006 06:06

Hello Randy!

I also worked for General Dynamics -Electric Boat Division up in "Rotten Groton, CT"...
You know, the division that built US Nuclear Submarines... and many other outfits where QUALITY was the number ONE PRIORITY!!!
I've been welding for over thirty years now and, have been teaching for at least 10 years so, I've also been - there done that!!!
Now, all I was trying to do was give you my gist of "innershield" which by the way is a brand name for Lincoln's self shielding flux cored wires. ESAB has never used this brand name...

NEVER did I imply that quality was to be dead last on the priority list for your job so, do'nt even go there!!!
Now, I'll give you the benefit of the doubt that you misunderstood my statement... BTW, what is your position title in your company if you do'nt mind me asking?

Now that we have some specifics to your project, I would like to make a suggestion...
Since you're concerned about how well the quality of the welds will be , why do'nt your company first develop a WPS, have your welders tested to that process by a third party inspector or any inhouse inspector that's qualified in dye penetrant testing, then have the PQR's on record so that you have CYA!!!

Check the contract documents to see if they meaning the customer, does not require the welders to be qualified to any specific code or standard because if they do (more than likely), then they must be qualified for this job.

I personally would NEVER accept a laborers word that they will
"personally guarantee that the tank wo'nt leak"...
They can claim all they want about previously being certified (they really mean qualified), but that does'nt mean that they are NOW!!! So take a tip from me and CYCA (cover your company's ass) and yours by relaying my suggestion to make sure that the welders are currently qualified to weld on this job even if the contract specs do not call for it specifically because if this is the case, then I would contact the engineer of record to ask for a minimum standard workmanship qualification requirement for the welds...

Do you have a CWI on staff? Lots of questions still to be answered for this post so, I'll wait for your reply.

CBIsteel said it right: "Proper Planning Prevents Poor Performance"
The 5P's to any successful project completion....
This is how the pitcher for the NY Yankees,
(a native New Yorker like myself) The Great "Whitey" Edward Charles Ford Pitched!!! He ranks 1st in all time world series wins, and 1st in world series consecutive scoreless innings with 33 & 2/3, breaking Babe Ruth's record of 29 & 2/3 innings...
You've got some REAL big shoes to fill!!!
I should know, I've been a DIE HARD Yankee fan since 1958!

Respectfully,
SSBN727
Run Silent... Run Deep!!!

By whiteyford M1A1 (**)

Date 03-15-2006 02:54

Hi SSBN 727
Please excuse my earlier challenge, I can't help myself sometimes when there a chance to play devil's advocate:) I also tend to agree with your take on time and profit. A forum such as this is great for exchanging different opinions from various backgrounds and viewpoints.

I truly miss the sense of accomplishment and pride in workmanship that I experienced at the Lima Army Tank Plant. I sense that you share similar sentiments about Electric Boat. Where do you teach?

My current position is as a Consultant Inspection Project Manager for PennDot on an 18 Million dollar bridge and roadway construction project. This work is by contract and seasonal. During the off season I assist with various research and forensic investigations with pavements. Any left over time I spend doing welding jobs in my workshop and cutting firewood. I volunteered as a committe member for a local vocational welding program for 11 years.

As for CWIs, WPS and PQR these don't mean anything to the company. As far as contract language nothing addresses qualifications, certification or proceedures. I offered to write a QC plan but was told it wasn't needed.

Note that I mentioned forensic investigation above. It was explained in related terms that should this project ever end up in court they would loose thier butts. We also do occaisional work under D1.5 !!!!

This is the 3rd time I've cried wolf over legitimate concerns and my last. I'm just along for the ride now. Hopefully it's not tttooooo Deep

You mentioned the 5Ps, we got 7, Piss Poor Planning Provides a Piss Poor Product.

Sorry for the generic use of Lincolns Innershield Tm actually the samples that I made were with Lincoln. ESAB was used on the tank. I stopped by to take a looksee. They're pretty much finished and I gotta tell ya at a glance most of it looks good, even looks like they marked previous stops and starts for staggering purposes on the multi pass joints. On closer inspection there are about a hundred locations where more weld was added for repairs of some sort. Most likeley porosity as it didn't take long to find pinholes that weren't addressed. Would this stuff be susceptable to toe line cracking as some repairs are to a single toe line. By repair I mean weld on top of a defect not a properly excavated repair. By the looks of the verticle down the travel speed looked fast on some sloww on others, it doesn't appear that they established a consistent method.
I'll Keep ya Posted

Thanks for all the Whitey Ford stats it's been a long time since the Bio.
Very Respectfully Yours
Randy

By MBSims

Date 03-13-2006 23:17

We have not used self-shielded wires on any fluid-containing equipment. But we've had some experience with contractors using it on light structural work and ductwork. In those cases, we had a lot of problems with weld quality and appearance, and no longer permit the use of self-shielded wires on our projects. Personally, I would not want to use it on a water tank and have to deal with the leaks and quality issues that would result. Perhaps someone out there has had better experience and found the "secret" to making it weld right. But, it is apparent that the technique is not intuitive for most welders and some amount of welder training would be required to do it right.

By MBlaha

Date 03-14-2006 11:58

I used to help build water towers and spherical gas holders. We used to use lots of Inershield NR203 if memory serves for everything out of postition and NR211 for flat work. We never had much trouble making X-rays and that was a big part of our extra money as we were paid piece work and picture money. To the best of my knowledge, not one of these ever failed or fell down. I always felt it was a little harder to clean the root pass, but after that the root pass, the slag would peel off if the weld was put in properly just like the slag will peel off a well laid 7018 weld. All it took was proper welder training and care when welding to produce very sound welds.
The spheres were pressure vessels that we would test at 100psi upon completion. Not one ever leaked nor did a single water tower ever leak.

Mike

By MBSims

Date 03-14-2006 18:04

Glad to hear that some have had better experience with it than we have.

By CBISTEEL Date 03-14-2006 00:51

hello Randy,

Try lincon innershield nr-211mp.Ihave mostly used it on flats but it is user friendly and produces a nice weld.proper volts/amps/wire speed is very important and most wires have different set ups.Proper planning prevents poor performance.

By aevald

Date 03-14-2006 07:12

Hello Randy, is this an onsite build or are you fabricating this in a shop and moving to the site? If this is shop built I would definitely not go with the self-shielded welding process. If it is site built I would have some reservations on using the joint configuration that you have described and self-shielded wire process or any other sort of process. Personally, this is a slag trapper waiting to happen, just my opinion. If you do end up using the self-shielded wire check closely to be sure that the wire is designed for multiple pass welding, from the sound of the joint type you will definitely require multiple passes to complete the joints and not all self-shielded wires are designed for this purpose. Some wires are susceptible to cracking when more than one pass is layed down on top of the other. Since this is an open-top tank the only pressure present would be generated by gravity, does it really require a full-penetration type weld joint? I realize some of these questions might not have answers that allow for changes if the engineering has already been completed and accepted, but they should be food for thought. I would be interested to hear how this all plays out for you. Best of luck and regards, aevald

By agong

Date 03-14-2006 14:20

Randy,
We have experience using self-shielded flux-cored wire for oil and gas pipeline (Lincoln NR-207) and oil tank building (NR-232). There's no problem by X-RAY tests.
I like what SSBN727 said: CBIsteel said it right: "Proper Planning Prevents Poor Performance"
Whatever processes you prefer, you have to have qualified people to do that. A wire supplier onsite training would be help a lot.

Regards,
AGong

By whiteyford M1A1 (**)

Date 03-15-2006 03:35

Hi eavald
Thank you for your interest.

I'm afraid the damage is done, it's pretty much complete,,,,,,it was built onsite (please read my other posts).

The design was done by an engineer in an unrelated field. Thus some odd joints ect.
Thank you
Randy

By aevald

Date 03-15-2006 04:44

Hello again Randy, I guess it just goes to show that in the big scheme of things as much as all of us try to use good sound logic and common sense when we are involved in a process, we can't be responsible for all of those involved. Don't lose your positive perspective when you are involved in anything and continue to try to do what you feel is correct and right. If no one speaks up when they see something worth questioning we'll all end up suffering a bit more as a result of it. Have a good one sir. Regards, aevald