pipe welding test

Date 05-24-2007 02:58

Practice my boy, practice.

All kidding aside, it takes practice and plenty of it to develop the skills needed to be able to pass a pipe test on a consistent basis.

Start by welding large diameter pipe and progress to smaller diameters when you can weld the large diameter pipe with ease. Small diameter pipe is more difficult to weld than large diameter pipe. Likewise, thin wall pipe is typically more difficult to weld than heavy wall pipe.

Contrary to what may be inferred by ASME Section IX, most welders will agree that austenitic stainless pipe is typically more difficult to weld than carbon steel pipe. When you feel you are proficient with carbon steel pipe, try welding some stainless steel pipe.

Good luck - Al

By Tommyjoking (****)

Date 05-24-2007 11:01 Edited 05-25-2007 08:24

if you have done vessel work then you are probably already familiar with a 5p. You also are already making high integrity welds cause your are qualifying on code work and getting shot regularly. Your looking for the same results in vessel work as in pipe work...shoot a good kodack. Carbon pipe work will most likely involve 5p and 7010 (some times 7018) of different varieties so get use to those rods if you want to do carbon work///. Stainless work will involve a 308 a lot so get good running a 308 horizontal or uphill...Somtimes tig (heliarc) welds are required on stainless work. The bright side is you just weld...little to no grinding....no fit up or rare (job)....and no air arc (YEA!)

803056 advice is pretty spot on running a stick on larger pipe is much easier then on small pipe. Practice running 45 degree bevels with an open root (keep root gap small like 1/16 or so) and fill em up...do these with the joint in a vertical line.......if you can handle verts or 5g with the pipe I do not think you will have any probs with is 45 degree vert (6g) or with it horizontal. When you can do it well without moving the pipe in any way try a smaller pipe. Start out with 12 to 16 inch pipe if you can and progress down to 4-2 inch. When you can run beads that you belive will shoot on 4-2 inch you will not have any problem going on a GOOD pipe job. Practice practice practice....it took me a long time to get comfortable and reliable stick welding pipe...not the rule but for me it was hard to get it down. Hopefully some of the full time pipe guys will chip in on this......pipe work is a whole different nich of welding in the field really.....but if you can do it well I think you can do just about any joint.

By Cole Welding (**)

Date 05-25-2007 01:10

Thank you. I do have lots of scape pipe in my back yard. I will get started at in this weekend. i have from 24 to 2 inch pipe. i know that lots of companies like to test on the 6G position. I am just getting started so i my be on here from time to time asking dumb questions. And is it any different running a tig rig off a engine driven michine then a shop machine????

By Tommyjoking (****)

Date 05-25-2007 07:18 Edited 05-25-2007 08:11

And is it any different running a tig rig off a engine driven michine then a shop machine????

not really but you will probably want a remote for it if your machine accepts one. I like a thumbwheel setup myself but most guys get by with a simple on/off switch. Whats hard about tig in the field is keeping the wind away from your joint...(think cardboard and masking tape...weld blankets over your head... LOL). Another problem is running aluminum on a portable rig cause the high frequency restricts your lead length....but your not going out to find aluminum pipe jobs either! Auto lenses are also GREAT when your tigging off a ladder, one arm hooked around the pipe etc. GTAW is the exception not the rule in field pipe work...its slow so its not used a whole lot.

Keep us posted on how it goes....there are plenty of real good pipe welders on this forum who can lend some solid advice.

By Cole Welding (**)

Date 05-25-2007 22:33

A friend of mine was telling me that i have to put the rod through the pipe to weld up the bottom. so i triews that and i didnt work is that to best way to put a root in a pipe?? i am using 12 inch pipe??

By ZCat

Date 05-25-2007 22:44 Edited 05-25-2007 22:56

I welded tons of TIG in the field, you just have to jack the argon up.

On the bottom, you need to feed the wire from the inside, or it is probably gonna come out flat or sucked back. It takes some practice. You can generally run a little hotter on the bottom than the top and sides.

What size gap and wire are you using? You need at least a 5/32 gap and a 1/8 wire on 12".

By Cole Welding (**)

Date 05-26-2007 00:28

I put a 3/16 gap in it. Bcause i am used to running head seams with mig with a 1/4 spacer in it

By ZCat

Date 05-26-2007 03:16

That oughta work, too. You need to be able to wiggle that wire around in there without it getting hung up.

By darren

Date 05-27-2007 02:50

what is 3g? i only know of 1,2,5,6, on pipe
thanks
darren

By aevald

Date 05-27-2007 03:28

Hello darren, you are correct in describing the 1,2,5 and 6G on pipe. the 3G(vertical) and 4G(overhead) refer to plate positions. Regards, aevald

By darren

Date 05-27-2007 07:38

although each day is slightly different after a while they all become just more "blue light"

i find oblique angle saddle welds that are welded in position (or out of position depending on who's describing it) the most difficult. at least to make look pretty or to do quickly
especially on large diameter pipe or vessels.
even very good fitters cannot give you a consistent root gap on the oblique angle saddle interfaces especially if it is oblique on two axises. i really respect the fitters who can do those well. i help fit them but would not want to tackle them myself without a few more years experience. especially ones that have one mm> tolerances
if you don't sequence your passes correctly things can get pretty tight awfully quick. and the ut picks up the problem a lot easier than rt.
darren

By Cole Welding (**)

Date 05-27-2007 19:55

I have been praticeing with the tig on the bottom of the pipe and i have been geting lots of suck back. Am i run my machine to hot ???? i do fair on the sides and top but it kinda thin in spots and heavy in spots how do i smooth the spots out??

By ZCat

Date 05-28-2007 04:01

the heavy spots are too hot. Don't know about the bottom, it could be too cold OR too hot. Try piling more wire in it. Probably too hot, if it was too cold the wire would be sticking to the puddle.

You have to figger out what works and do it all like that. :-)

You need to hold the end of the wire about an eighth or so above the pipe I.D. and let the puddle flow down to the edges.

By Cole Welding (**)

Date 05-29-2007 02:14

ok i will play with it .... a friend of mine wants to know what copper welding is... it is brazing???? and threated pipe welding is??? is it pipe that has been threated together and then you weld the joint up??