Thread: The Tig Files - Voyage towards pressure level welding

Heres my Setup:

2G - 117amps root n hot pass
125 Amps Cap
Filler rod 2.4 S4
Landing: 1.6
Root gap 3mm
I freehand throughout

5G 114amps root n hot pass
125 Amps Cap
Filler Rod 2.4 S4
Landing 1.6
Root gap 2.4mm
I walk the cup throughout

I use a large Jumbo sized No:10 cup and a Gas Lens running 2.4 electrodes. Depending on who you listen to theres not much difference between using S2 S4 or S6 Filler rod I prefer S4 wire in my opinion its more fluid and washes in better (ideal for root runs) I used S4 wire on the day of the test with excellent results......................................

If your learning this kind of welding i highly recommend you get your hands on a tong tester to see how many AMPS your pulling in real terms and a heat gun so you can get an idea of optimal interpass temperatures for me this ended up being between 100-200 degress c....................

Regards Lou

Gidday

AS you'll here from any Welder worth their Salt Preparation is the key. The coupon MUST BE CLEAN shiny metal clean even on the inside of the pipe. Take all the scale off n prep at least 25mm down from the inside of the Bevel of your pipe..............this helps avoid oxidisation and pinholes on the inside of your rootrun........................

Get rid of burs and ensure your Fitup is spot on!.............................

Typically I did all my preps with a Linisher and a No60 Flap wheel on the end of a die Grinder..........This worked OK but a solid Bur of the ceramic type does a much better job on the inside of the Pipe......................

Once shes right to go you lay 3 Tacks no greater than 12mm @ 120degress

Regards Lou

Gidday

Your welding has to meet code requirements of Australian Standard 1796 basically a high standard............

Scour the net ask advise of anyone who'll give you the time of day! By the time I sat my Cert 7 I had a large international support team of teachers welders forum members and masters to draw information from and ask advise about what i was struggling with.............

Indeed i got more help from the Internet than my teachers ............

Heres an example of some of the Journey including some pictures of my early welds and the progression closer to test day when I just about had things nailed

2G, 5G & 6G Help required

In saying this a big shoutout and thank you to all the forum members here who gave me a hand........................... Muchly appreciated!

Regards Lou

The End Result

I Passed!

Whooooooooooooooooo Hhhhhhhhhhoooooooooooooooooooooooo!

Im now a coded welder certified to AS1796 Cert 7

In saying this all the hard work has taught me its just another weld and the beginning of the journey..........................

Next week Im beginning My 6G so will take a lot more pictures and have an in depth look at how to pump out a 6G

Regards Lou

Onya mate

There was never any doubt.

Outcome result is proportional to the input.

Don't worry about 6g and its just another test.

No trouble for the prepared.

Think 6P

Proper preparation prevents pi$$ poor performance.

Well done.

Grahame

Congratulations Lou, nice to see - and I love your attitude

Originally Posted by NewLou

Gidday

Has been a while since Ive landed a post so thought I'd better get back into it. Just to get things going heres some more pros in Action:

Regards Lou

Hey with the 2nd video, I couldn't work out why they seemed to be recapping the weld with a bunch of stringers... was it to get rid of some surface imperfections? or using a harder rod or what?

Gidday mick

Industry Standard is usually root & hot pass tigged out then caps are done with Stick unless welding procedure states otherwise...............However the bottom line is the Welding procedure will be dictated by the environment & the service conditions the welds being laid will live in/ cost is also a deciding factor. For example in Nuclear reactor work the caps would also be Tigged as there are conditions where other processes like stick welding cannot be used...................safety etc

In general terms The Tig side of it is done because GTAW is a much cleaner process and easier to control heat input..................thus reducing defects & minimising changes in the metal structure in and around the HAZ (Heat affected Zone) of the Weld.....................

Capping out with stick is quicker and saves the Boss money!........................Also laying stringers once again reduces heat input and is considered a stronger method of welding when controlled properly. I cant remember if they showed it in the Video but a infared heat gun is used to check the temperature of the Job between welding passes to control the heat eg: stringers wont be laid until the pipe cools to 200 c (This is called interpass cooling)

Regards Lou

thanks Lou, yeah I can see how you can lay down more metal cheaper with stick, but it seemed that that weld had already been filled (well would have been before it was ground flush)... I did notice just a bit of undercut in places, but apart from that it looked good to me. So that got me wondering. The attached pic is what I'm talking about. Cheers - Mick

[edit] OK, I think I've got it, some of the runs previous to this where done by stick too - I was assuming it was tig up to this point.

Hey Mick.................

Yup only the root n hot pass are tigged!

A bit of Undercut under the cap is not considered a problem as it will get filled...............

These guys go as fast as they can and push the limits to what they can get away with within the Code they are working under.................time is money!
under non commercial conditions its likely they'd weld like gods with no defects whatsoever................

All the clean up grinding is prep for the Capping and will be part of the welding procedure they are working to ................... As long as they are within the code they are working under and pass X-Ray the weld will get a green light!

From memory they showd some footage of the finished cap and it was a cracker!

Regards Lou

Gidday

I was Lucky enough to stumble across a post from a Master Tig Welder from Canada. He was good enough to post some in depth information and examples of Pressure welds and X-Rays. What a clean X-Ray looks Like and some examples of defects. Highly recommended for those looking to get into this kind of work!.......................Im always interested in body positioning and sneaky places to prop the handpiece n fillerrod! The guy looks comfortable HUH Lol

New Member- Nuclear Pipe & Pressure Vessel Weldor - WeldingWeb™ - Welding forum for pros and enthusiasts

While im on this I think its one of the most under taught and under emphasised subjects @ TAFE. 4 me its nearly the most important thing to learn.....................

Learning how to avoid getting yourself in a Bind
Correct body positioning
Handpiece, Fillerrod & Worklead Management
Learning how to identify and Utilise Propping points
Correct Fillerrod use and Manipulation

Are all really important skills to develop and constantly look to improve..................



Regards Lou

Hi Lou, all the best with your future welding ambitions.
And how about this?...Has to be the freakiest aluminium welding I've ever seen.

Miller - Power and Perfection: Custom Intake Manifold Fabricator Relies on Inverter-Based TIG Welding Technology to Reduce Heat Input, Improve Aesthetics

Hey Doc

Yeah its amazing what a 10K rig and a sergically clean environment can do for your Welding............Speaking of Crazy Welding check these out!...............

[ame=http://www.youtube.com/watch?v=atgvFrgOArc]TIG WELD TITANIUM WELDING tig welding titanium - YouTube[/ame]

[ame=http://www.youtube.com/watch?v=_Tv25KEvbzo&feature=plcp]PINOY WELDER nickdanz WELD TITANIUM GRADE 12 WESTERN AUSTRALIA.mp4 - YouTube[/ame]

Regards Lou

Gidday

Started training for my 6G today! The teachers Ive been working with recently have been excellent and are also allow me to do some Stick and Flux Core training................

Essentuially at the moment im just getting my hand in so thought I might share the journey so that you guys can see the progression & i can pass on anything I learn...........All are welcome to ask questions critique join in rar rar rar.....................

To start I thought ID show a few prepped coupons: