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3G FCAW Welding Certification

Passing a 3G (Vertical Up) Flux Cored Arc WeldingCertification

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MarkingoftheFCAW3GWeldingCertificationTest

FCAW3GWeldCapCleaned 3GFCAWRootandFaceBendwiththeAlternate

This page is about how to pass a 3G flux cored arc welding certification. Just like my otherwelding certifications I wrote down all of the detail on how to pass this weldingcertification and took pictures to illustrate the procedure.

This is a very easy welding certification topass as long as the welding machine is setright. I literally have not picked up fluxcored welding wire since 1996 and it tookabout ten minutes of practice before I tookthis welding certification. If you can Stickand MIG weld, then flux cored weldingshould not be a problem for you. As easy asthis test is I did fail it the first time. So this isthe second time I am taking this weldingcertification. The failure of the first 3G

certification was not caused by any weld defects. The weld held up fine but whathappened was the test coupons broke about 1/8 of an inch outside of the weld area. At thetime I was taking the test many other welders were failing their welding certifications forthe same reason. What we all had in common was, when taking our welding certificationsour test coupons were too close to the exhaust vents. Failing a welding certification thatcosts only $20 was not a big deal to me, but the fact I had to do it again got me thinking.

When I went home I pulled out my metallurgy book and started looking for anexplanation. The most likely cause for this type of coupon failure seems to be coming fromthe Heat Affected Zone. I dont know if what I am about to mention is completely true.Remember I am not a metallurgist or a welding engineer. I am just a welder and this isjust a theory! Since all of the welding certifications that failed were too close to the ventsin the welding booths and none of them broke in the weld area. I believe that the causewas coming from the test plates cooling too fast. The area where the test coupons failed isalso where the metal is known for forming a coarse grain structure, causing that area toharden. Since that time, nobody at the school has tested with their test plates to close to

the exhaust vets, and since that change, no one has had this type of coupon failure!

The pictures I am posting are going to be mixed up between the first and the second test.When I did this certification the first time, I took a lot of pictures showing how to preparethe test coupons, and how to remove a backing bar. Outside of preparing the test couponsand removing the backing bar all of the other pictures are from the test I passed.

Who Should Take a 3G FCAW Certification?

Flux cored arc welding is typically used when there is a lot of welding to do and it is outdoors. FCAW is used in industrial shut downs for welding of boilers and pretty much anyindustrial construction projects that need high quality welds fast. For certain jobs having a3G flux cored arc welding certification will get you in the door before someone who doesnot. It may also help in getting a structural welding job in a shipyard. I do want to mentionthat if you are going to test at a shipyard, you will also need to pass a 4G weldingcertification. The standard shipyard qualification test for structural flux cored arc weldersis a 2G, 3G, and 4G, 1 inch thick plate test, with a ceramic backing tape. So if you are goingto test for a shipyard, make sure you can pass their tests!

AWS D1.1 FCAW (Vertical Up) Welding CertificationProcedure Specifications

The specifications for this welding procedure are very simple compared to my otherwelding certifications. The AWS D1.1 3G FCAW procedure qualifies you to weld in the 1F,2F, and 3F positions and the 1G, 2G, and 3G positions. You are qualified to weld in the flat,horizontal, and vertical positions and not the 4G or overhead position.

This welding certification I passed is the limited thickness procedure that qualifies me toweld carbon steel from 1/8 to of an inch thick plate.

The welding certification is just like any other AWS welding certification when it comes toexpiring. If you do not weld using the FCAW process, this welding certification expires insix months, or 180 from the time the test was taken. Every six months an employer or awelding school needs to sign the welding log in the back of the certification to keep it up todate. If you are not working simply take a refresher course at a local welding school to

keep the welding certification up to date.

Here are the procedure specifications:

Welding Process. FCAW

Position. Vertical

Vertical Progression. Up

Joint Type. Butt

Backing. Yes

Backing Material. ASTM A36

Root Opening. 1/4 to 5/16

Grove Angel. 45 degrees

Back Gouge. No

Base Metal. ASTM A36

Type or Grade. Steel

Thickness. Groove. (in) .375

Filler Metals AWS Classification. E71T-1

Shielding Gas. 75% Argon / 25% Co2

Gas Flow Rate. 40 50 CFH

Gas Cup Size. 5/8

Contact Tube to Work Distance. 5/8 to 3/4

Electrical Characteristics. DCEP(direct current electrode positive)

Stringer or Weave Bead. Either

Interpass Cleaning. Mechanical or Wire Brush

Electrode Diameter. .045

How to Pass the FCAW D1.1 Welding Certification

FCAW Machine Set Up

Setting up of the flux cored welder was not hard. I used the same Millermatic 350P that Idid my 3G vertical up MIG welding certification with. All I did was change the wire fromMIG wire, to flux cored E71T-1 dual shielding wire, and then the rollers. The bottle of gas

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on the machine was already C25 gas. The gasflow rate the procedure specifies is 40 to 50CFH but I only used about 30 CFH. I amwelding indoors, inside of a welding booth,with no real drafts, so my gas coverage wasmore than enough.

The settings I used were 23 volts and mywire speed was at 218 IPM (inches perminute). I dont remember the exactamperage but those settings on mostmachines should put you into the properrange for vertical up welding. Remembereach machine is different; even if you areusing the same make and model, the settingswill vary depend on how the machine iscalibrated. When welding the sound had afast deep crackle to it. With flux cored arcwelding there are two types of wire transfer.Globular and spray transfer. True spraytransfer has just a hissing sound to it,otherwise when the amperage crosses a

certain threshold the weld crackles but it is spray transferring to the joint. This isespecially true with flux cored welding!

Joint Preparation for the FCAW Certification

The test coupon preparation is the same as all of my other 3G welding certifications. Inthis 3G welding procedure the notes are taken from the same section of the AWS code thatare used for the 3/8 inch limited thickness test procedure.

I received my test coupons that were pre-cut and ready to prepare. All I did was grind theface of the test plates a minimum of one inch back from the bevel and a minimum of aquarter of an inch back on the back of the bevel. Next I cleaned the backing bar to baremetal with a grinder. And then cleaned the oxidation off of the bevel to bare metal.

After that the bevel angles were checked with a protractor by myself, then the weldinginstructor rechecked them. Everything was good and then I tacked up my coupons. I set toroot opening with two 1/8 inch welding electrodes and then the test plate was inspectedfor fit-up.

Pre-Inspection of the Test Coupon

The test coupon was put into the vertical position and marked with a white marker tomake sure I do not move the plate anytime during welding or cleaning. This is donebecause the AWS procedure notes state:

The Root Pass

Now the test will be placed in the fixedposition. The test piece will be marked inposition with a marker and the inspector maysee the test anytime during the testing.(DURING THE TEST, THE PIECES SHALL NOTBE MOVED IN ANY DIRECTION AND ORREMOVED FROM THE TESTING PLACEWITHOUT THE INSPECTORS APPROVAL.)

The root pass was done by building a shelf of weld and moving upward from there. I usinga side to side weave while washing into the sides of the bevel. I did not pause much on the

sides. All I did was use a steady weaving motion and the root came out fine. This specificprocedure does not say you need any restarts so I did not have any. The first picture belowis the weld still covered in slag. All I did to clean the weld is use a wire wheel and the slagcame off with ease. The second picture is the cleaned root pass. After that the root of theweld was inspected because the welding procedure states:

The root of the weld shall be inspected, and there shall be no evidenceof cracks, incomplete fusion, or inadequate joint penetration. A concaveroot surface is permitted within the limits shown below, providing thetotal weld thickness is equal to or greater than that of the base metal. Themaximum root surface concavity shall be 1/16 in. (1.6 mm) and amaximum melt-through shall be 1/8 in. (3 mm)

The Hot Pass

Before welding the hot pass I did let the plate cool to the point that I could almost touch it.The hot pass was done using the same technique as the root pass. All I did was just use asteady side to side weave with-out pausing too much on the sides. I did the fill in a single

pass and had no restarts. With flux cored welding the wire does most of the work. It issuch an easy process to use and takes very little skill. All I did to clean the slag was use awire wheel and the weld was cleaned.

The Cap Weld

Again before welding the cap I let the plate cool down till I could almost touch it. The capof the weld was done using a weave technique while washing the weld about 1/16 of aninch past the edge of the bevel. I held the sides for about a second before moving back tothe other side. The cap was also done in a single pass just like the root and hot pass. Itypically weld past the edge of most bevels. What that does is give good weld penetration,preventing face bend failure and undercut. The cap of the weld came out to be 3/32 of aninch over the face of the bevel (just perfect). It had almost no undercut and it was morethan acceptable. The acceptance criteria for the face of the weld are as follows in thewords of the AWS:

The face of the weld shall be flush with the surface of the base metal,and the weld shall merge smoothly with the base metal. Undercut shallnot exceed 1/32 in. (1 mm). Weld reinforcement shall not exceed 1/8 in. (3

mm)

The first picture below is the weld still covered in slag. The second picture is the slaglifting itself off of the cap. What I like about flux cored arc welding is how easy the weld isto clean and in many times the slag just falls off by itself. The last picture is the capcleaned with a wire brush.

Bend Test Coupon Preparation

The test coupons were prepared just like myother welding certifications. First you mark acenter-line on the plate. Then another line 1inch above the center line and another line 1inch below the center line. This is the sectionthat can be used as an alternate coupon inthe event of corner cracks with no evidenceof slag inclusions. Next is marking of theactual root and face bend specimens. Usingthe top and bottom line, mark another line aminimum of 1 inches above the top line,

and then 1 inches below the bottom line. The minimum width of a test specimen needsto be 1 inches wide. Otherwise that test specimen will fail on the spot! After that theywere marked by the welding instructor for a root and face bend followed by me cuttingthem on a band saw.

Backing Bar Removal

The backing bar removal was mostly done using a vice. First I put the coupon into the viceand took a grinder to the center of the backing bar gouging it. I kept grinding out thecenter till I was about 1/16 or so away from the back of the test plate. Next I locked ontoone side if the split backing bar with the vice firmly. After that all I had to do was pressdown on it like a lever. I kept repeating this until all of the backing bars were removed onthe test coupons. The pictures below are from the first welding certification that I failed. I

am posting them because they give a good illustration of how to remove a backing bar.

After the backingbar is removed,the face and theroot of the weldneed to beground flush tothe base metal. Ifyou grind pastthe base metalthe test will berejected forexcessive

material removal. After grinding down the root and face of the weld, I used a belt sanderto round the square corners, followed by a buffing wheel to polish the weld area.

FCAW 3G Bend Test

The bend test went very well on these coupons. If you remember I took this test beforeand the test coupons failed before the weld area got a chance to bend all the way. On thistest I had two bends done, a root bend, and a face bend. Below are pictures of the testspecimens being bent.

Both couponswere bent and Idid not need thealternate. Theresults wereflawless and this

is how I passed the AWD D1.1 FCAW 3G Welding Certification!

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