Comments on Pipe Weld!

[Robertbanham]

Hello All.

Here are a few pictures of a TEE Branch i welded onto a pipe in 4"

I used a 2.5mm rod to root and 3.2mm rods to fill and cap.

This is the first time i have attempted this weld.

Any comments will be appreciated.

Thankyou...

 

[BrokenBiker]

You need to clean the steel back to shiny with a grinder. That would fail a weld test just on poor prep.

why did you use 3.2 to fill and cap? How many passes did you run?

 

[gordon stephenson]

Yes, clean to bare metal first. Your welds look a little cold to me.

 

[BrokenBiker]

in wondering did you up the amps when changing to 3.2 rod? They could do with being a bit hotter

 

[wheresmejumper]

Its a pretty good effort.they dont look that cold overall, tie in to the sides well

 

[Robertbanham]

in wondering did you up the amps when changing to 3.2 rod? They could do with being a bit hotter

Hey brokenbiker

I did three passes a root a filler pass and then capped it. I thought it would be easier to fill and cap with a bigger rod to be honest was that a bad idea? And I know this will sound silly but how can you tell it's needs to be hotter and why is that? Sorry to ask stupid questions.

 

[BrokenBiker]

3 passes seems a bit much for that joint, i personally would have put a root in and then a weaved cap with the 2.5 rods, but i am not a coded pipe welder so please do not quote me on that if you are practicing for a test or something. It is just the method i have adopted for the welds i do, none of which are pressure vessels.

the reason i say they should be hotter is because there doesn't look to be much fusion at the toe, but i am looking at the pics on a phone so i may be wrong. If you turn the amps up when using the 3.2 or just keep using the 2.5 the toe should melt in a bit better, but again i may be wrong just commenting on what i can see.

your technique looks ok, no real spatter which indicates a good and consistent rod angle, travel speed looks ok, weave on the cap looks consistent from what i can see.

EDIT** just managed to open the pics up and the toes look better than i initially thought, could still do with maybe a few more amps but not many. Its surprising what difference 5 amps will make sometimes

 

[Bill Edwards]

What's it for? Practice or something holding pressurised gas?

If it's important then you must clean all the metal back to be free from paint, oil and dirt. This includes the bits you can't actually see when the joint is assembled - think where the metal will be melting.
I'd also be grinding back the weld where you stop to ensure full penetration at each stop/restart (start welding on the remains of your last weld).
I'd also have said that in most cases a root run and a weave should suffice.
How thick is the metal?

Other than the lack of proper preparation it doesn't look a bad effort though. You certainly don't need much more power, and the weave looks quite consistent.
What welder are you using? Do you have fine control over the amps?

 

[Robertbanham]

3 passes seems a bit much for that joint, i personally would have put a root in and then a weaved cap with the 2.5 rods, but i am not a coded pipe welder so please do not quote me on that if you are practicing for a test or something. It is just the method i have adopted for the welds i do, none of which are pressure vessels.

the reason i say they should be hotter is because there doesn't look to be much fusion at the toe, but i am looking at the pics on a phone so i may be wrong. If you turn the amps up when using the 3.2 or just keep using the 2.5 the toe should melt in a bit better, but again i may be wrong just commenting on what i can see.

your technique looks ok, no real spatter which indicates a good and consistent rod angle, travel speed looks ok, weave on the cap looks consistent from what i can see.

EDIT** just managed to open the pics up and the toes look better than i initially thought, could still do with maybe a few more amps but not many. Its surprising what difference 5 amps will make sometimes

Thank you very much for your comments, you've given me more understanding of what is actually happening in the weld..I will try with a few more amps and see how that goes...I'll also give it a go using 2.5...

Cheers mate

 

[BrokenBiker]

the way I would do it would be to set the machine slightly hot for the root, move fast and no weave, just focus on getting the weld right into the root. then for the cap I would arc on the middle of the weld, flick out to one side, hold a sec, flick over to the other side, hold a sec, flick back over and slightly down, hold for a sec etc. basically using a 'z' shape and holding on the edges of the weld to really tie into the toes

 

[aidank]

did you grind the pipe to a VEE for the root

what thickness are the pipes

what amps for the 2.5mm and 3.2mm