Tig welding tips, questions, equipment, applications, instructions, techniques, tig welding machines, troubleshooting tig welding process
buckwheat
  • Posts:
  • Joined:
    Sun Oct 04, 2009 9:08 am

:lol: Hello
Having great difficulty putting in tig root pass in 4 inch schudule 40 pipe. Can you offer any tips Thanks
flyingnunrt
  • Posts:
  • Joined:
    Tue Oct 06, 2009 4:22 am

What is the thickness and joint preparation, amps etc that you have been using?
welder689
  • Posts:
  • Joined:
    Thu Oct 01, 2009 8:55 pm

Do you know how to walk the cup on an open root?
tigamajig
  • Posts:
  • Joined:
    Wed May 26, 2010 8:23 pm

.what is the root opening?
.are you starting at a tack?
.amperage?.
.
.
.the size of the pipe really doesn't matter, unless there is a breeze blowing through it.
.thickness?
.bevel?
.stickout?
speen
  • Posts:
  • Joined:
    Sat Jul 10, 2010 5:57 pm

here's how i do it.

first of all i would just like to mention that i weld with the workpiece in a vertical position, turning it around with a rotary table.

- first of all i make sure that the bevel nose is ~0, this makes for easier penetration.
- then i clean of all the parts using acetone or something simular.
- i tack the pieces together with a 3.2mm root opening. i just use a 3.2mm fillerwire.
- with the piece tacked up i place it on a plate with a little hole in the center, then i place my purge ontop.
- when it comes to amps, i would use something like 75 for stainless and maybe 90-100 for mild steel.
- fillerwire would be 2.4mm
- most of my heat is directed on the top part while i feed wire also at the top. i then drag it down to the bottom part.
- when i've completed the full 360 degrees i overlap about 10-15mm just to eliminate any lack of penetration.
OrbitalX
  • Posts:
  • Joined:
    Wed Oct 06, 2010 4:16 pm
  • Location:
    gaffney , sc

speen wrote:here's how i do it.

first of all i would just like to mention that i weld with the workpiece in a vertical position, turning it around with a rotary table.

- first of all i make sure that the bevel nose is ~0, this makes for easier penetration.
- then i clean of all the parts using acetone or something simular.
- i tack the pieces together with a 3.2mm root opening. i just use a 3.2mm fillerwire.
- with the piece tacked up i place it on a plate with a little hole in the center, then i place my purge ontop.
- when it comes to amps, i would use something like 75 for stainless and maybe 90-100 for mild steel.
- fillerwire would be 2.4mm
- most of my heat is directed on the top part while i feed wire also at the top. i then drag it down to the bottom part.
- when i've completed the full 360 degrees i overlap about 10-15mm just to eliminate any lack of penetration.
Man ! i could have fun welding beside you.
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