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outofstepper
Posted: Mon Apr 28, 2008 10:12 pm
Guest
Greets all & good morning.
would like to preface this by saying I'm not a full-time
weldor. Used to do alot more but now I like to pick
and choose my work -- 99% of the time its TIG --
typically Al & SS structural -- not a pipe weldor!

close friend of mine is a contract weldor and asked
me to lend a hand running tig root pass on a lot
contract (he'd follow up behind with a 7018 cap).

welding 3" sch 80 pipe on a bench. These are
elbow assemblies made of 1 elbow, an 8" extension
on each end, and 2 flanges. I only needed to weld
the elbow/extension.. not the flange.

I didn't need to bring anything except gloves and a
helmet -- everything else would be provided.

(They supplied an old scratch-start aircooled torch
kit wired to the oldest DC machine I've ever seen --
but thats a different story)

anyway, I found 300 of these assemblies already
"preped" and ready to weld. each was spot welded
and they used 3/8" rounds (with 3/4" mig
beads!) in four places around each joint -- every
90 degrees to set the gap -- which meant I could
only weld 'round the joint about 1.5" before I'd have
to stop and grind that 3/8 round out and fix the bevel
that the mig "tack" filled.

man this is getting long winded -- sorry.

bottom line is: is a 3/8" gap pure madness on 3" pipe?

i started welding these flat on the table (1G position)
but couldn't get a consistent profile on the inside
penetration. (all they had was 3/32" filler and 3/32"
tungstens).

Next, I flipped them up on their flanges and welded
each joint in a 2G position and I got much more
consistent results with a great profile on the inside.

One satisfactory completed piece, with only the root
tig weld, on two joints (less than 20" of weld bead)
took me exactly 45 mins (including the grind time).

Q: is it my lack of experience with pipe welding? is
a 3/8" gap on this size pipe normal? in the end the
welds looked good, inside and out -- got a cupwalking
ripple pattern even though I had to float it (don't know
how to walk) because of the CHASM I had to cross.

there were no prints / specs / etc to follow.. just
"here's your pile of stuff -- weld it up for us"

thanks for stick'n through this. Smile
Tony
Back to top
outofstepper
Posted: Tue Apr 29, 2008 1:47 am
Guest
Thanks Bruce.

These were all beveled by the way -- I was told that
ahead of time and thats what I found -- 60 degree with
maybe an 1/8" root face -- a bit hit and miss, I think
these were ground using a jig and angle grinder.

I expected to find no gap at all..

-Tony

Quote:

We laid a bunch of 3" sch 80 lines, 100% x ray, in a small field and
the pipe fitters gaped the joints about 1/8" (1/8" 6010 root and 7018
for hot and cover passes). We didn't use a bent rod, just the "that
looks about right" gage system. I would think that TIG would be the
same, or even less.

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)
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Bruce in Bangkok
Posted: Tue Apr 29, 2008 4:50 am
Guest
On Tue, 29 Apr 2008 01:12:48 -0700 (PDT), outofstepper
<post@fononica.com> wrote:

Quote:
Greets all & good morning.
would like to preface this by saying I'm not a full-time
weldor. Used to do alot more but now I like to pick
and choose my work -- 99% of the time its TIG --
typically Al & SS structural -- not a pipe weldor!

close friend of mine is a contract weldor and asked
me to lend a hand running tig root pass on a lot
contract (he'd follow up behind with a 7018 cap).

welding 3" sch 80 pipe on a bench. These are
elbow assemblies made of 1 elbow, an 8" extension
on each end, and 2 flanges. I only needed to weld
the elbow/extension.. not the flange.

I didn't need to bring anything except gloves and a
helmet -- everything else would be provided.

(They supplied an old scratch-start aircooled torch
kit wired to the oldest DC machine I've ever seen --
but thats a different story)

anyway, I found 300 of these assemblies already
"preped" and ready to weld. each was spot welded
and they used 3/8" rounds (with 3/4" mig
beads!) in four places around each joint -- every
90 degrees to set the gap -- which meant I could
only weld 'round the joint about 1.5" before I'd have
to stop and grind that 3/8 round out and fix the bevel
that the mig "tack" filled.

man this is getting long winded -- sorry.

bottom line is: is a 3/8" gap pure madness on 3" pipe?

i started welding these flat on the table (1G position)
but couldn't get a consistent profile on the inside
penetration. (all they had was 3/32" filler and 3/32"
tungstens).

Next, I flipped them up on their flanges and welded
each joint in a 2G position and I got much more
consistent results with a great profile on the inside.

One satisfactory completed piece, with only the root
tig weld, on two joints (less than 20" of weld bead)
took me exactly 45 mins (including the grind time).

Q: is it my lack of experience with pipe welding? is
a 3/8" gap on this size pipe normal? in the end the
welds looked good, inside and out -- got a cupwalking
ripple pattern even though I had to float it (don't know
how to walk) because of the CHASM I had to cross.

there were no prints / specs / etc to follow.. just
"here's your pile of stuff -- weld it up for us"

thanks for stick'n through this. Smile
Tony


We laid a bunch of 3" sch 80 lines, 100% x ray, in a small field and
the pipe fitters gaped the joints about 1/8" (1/8" 6010 root and 7018
for hot and cover passes). We didn't use a bent rod, just the "that
looks about right" gage system. I would think that TIG would be the
same, or even less.


Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)
Back to top
Bruce in Bangkok
Posted: Tue Apr 29, 2008 7:21 am
Guest
On Tue, 29 Apr 2008 04:47:49 -0700 (PDT), outofstepper
<post@fononica.com> wrote:

Quote:
Thanks Bruce.

These were all beveled by the way -- I was told that
ahead of time and thats what I found -- 60 degree with
maybe an 1/8" root face -- a bit hit and miss, I think
these were ground using a jig and angle grinder.

I expected to find no gap at all..

-Tony

I thought you were saying the joints had a 3/8" gap.(which I thought a
lot). The pipe we were welding was beveled (generally with an 8"
grinder) clamped and down hand welded. I will say that the welder and
the pipe fitter were part of the three man team so if the gap "wasn't
right" it got changed and I'm sure that they varied from crew to crew
but the specs (as far as I can remember) called for 60 degree vee with
1/8" root -- but it was quite a few years ago.

From what you say, you must be spending all your time getting a good
looking bead. Is it hourly pay or piece work?

Quote:

We laid a bunch of 3" sch 80 lines, 100% x ray, in a small field and
the pipe fitters gaped the joints about 1/8" (1/8" 6010 root and 7018
for hot and cover passes). We didn't use a bent rod, just the "that
looks about right" gage system. I would think that TIG would be the
same, or even less.

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)
Back to top
outofstepper
Posted: Tue Apr 29, 2008 9:05 am
Guest
On Apr 29, 6:56 pm, "SteveB" <toquerville,utah@zionvistas> wrote:

Quote:
What's your responsibility in this? If one of these leaks, is it going to
be blamed on bad joint design, an excessive root, or YOU? Sounds like you
got a bad design, questionable equipment, and not a lot of instructions.


In fact, thats why I'm posting here and not "working" Smile Took a few
days
to give their inspector a chance to look at them -- apparently he pops
in
with no real schedule.

Its hourly pay, not piece -- but I wanted to make a good impression.

Wanted to bring my own equip for day 2 but was told not to (guess the
pay's always the same and no point putting hours on my own tools?)
I did get real used to pulsed TIG -- but with this 4 foot gap I don't
think it
would've helped me any.

I'm told that these will be "Xray'd to 5%" -- I can't tell you what
that means..
maybe 5% of the whole lot?

Thanks for the input so far -- glad to know I'm not alone.

Evening all,
-Tony
Back to top
SteveB
Posted: Tue Apr 29, 2008 11:56 am
Guest
IIRC, the root opening should be the size of the filler rod as a very
general rule of thumb. It is difficult when you have to pick up the next
step from someone who obviously doesn't know what you do or how you do it.
Since you got in on this late, and didn't get to go to the planning meeting,
that makes it bad. If it's all beveled, a 3/8" root sounds excessive.

What's your responsibility in this? If one of these leaks, is it going to
be blamed on bad joint design, an excessive root, or YOU? Sounds like you
got a bad design, questionable equipment, and not a lot of instructions.

So much for "friends".

Steve

"outofstepper" <post@fononica.com> wrote in message
news:c08d4dbb-8d5f-4e9c-8d04-bf5e1cf95d61@24g2000hsh.googlegroups.com...
Quote:
Greets all & good morning.
would like to preface this by saying I'm not a full-time
weldor. Used to do alot more but now I like to pick
and choose my work -- 99% of the time its TIG --
typically Al & SS structural -- not a pipe weldor!

close friend of mine is a contract weldor and asked
me to lend a hand running tig root pass on a lot
contract (he'd follow up behind with a 7018 cap).

welding 3" sch 80 pipe on a bench. These are
elbow assemblies made of 1 elbow, an 8" extension
on each end, and 2 flanges. I only needed to weld
the elbow/extension.. not the flange.

I didn't need to bring anything except gloves and a
helmet -- everything else would be provided.

(They supplied an old scratch-start aircooled torch
kit wired to the oldest DC machine I've ever seen --
but thats a different story)

anyway, I found 300 of these assemblies already
"preped" and ready to weld. each was spot welded
and they used 3/8" rounds (with 3/4" mig
beads!) in four places around each joint -- every
90 degrees to set the gap -- which meant I could
only weld 'round the joint about 1.5" before I'd have
to stop and grind that 3/8 round out and fix the bevel
that the mig "tack" filled.

man this is getting long winded -- sorry.

bottom line is: is a 3/8" gap pure madness on 3" pipe?

i started welding these flat on the table (1G position)
but couldn't get a consistent profile on the inside
penetration. (all they had was 3/32" filler and 3/32"
tungstens).

Next, I flipped them up on their flanges and welded
each joint in a 2G position and I got much more
consistent results with a great profile on the inside.

One satisfactory completed piece, with only the root
tig weld, on two joints (less than 20" of weld bead)
took me exactly 45 mins (including the grind time).

Q: is it my lack of experience with pipe welding? is
a 3/8" gap on this size pipe normal? in the end the
welds looked good, inside and out -- got a cupwalking
ripple pattern even though I had to float it (don't know
how to walk) because of the CHASM I had to cross.

there were no prints / specs / etc to follow.. just
"here's your pile of stuff -- weld it up for us"

thanks for stick'n through this. Smile
Tony
Back to top
Private
Posted: Tue Apr 29, 2008 2:14 pm
Guest
"outofstepper" <post@fononica.com> wrote in message
news:c08d4dbb-8d5f-4e9c-8d04-bf5e1cf95d61@24g2000hsh.googlegroups.com...
Quote:
Greets all & good morning.
would like to preface this by saying I'm not a full-time
weldor. Used to do alot more but now I like to pick
and choose my work -- 99% of the time its TIG --
typically Al & SS structural -- not a pipe weldor!

close friend of mine is a contract weldor and asked
me to lend a hand running tig root pass on a lot
contract (he'd follow up behind with a 7018 cap).

welding 3" sch 80 pipe on a bench. These are
elbow assemblies made of 1 elbow, an 8" extension
on each end, and 2 flanges. I only needed to weld
the elbow/extension.. not the flange.

I didn't need to bring anything except gloves and a
helmet -- everything else would be provided.

(They supplied an old scratch-start aircooled torch
kit wired to the oldest DC machine I've ever seen --
but thats a different story)

anyway, I found 300 of these assemblies already
"preped" and ready to weld. each was spot welded
and they used 3/8" rounds (with 3/4" mig
beads!) in four places around each joint -- every
90 degrees to set the gap -- which meant I could
only weld 'round the joint about 1.5" before I'd have
to stop and grind that 3/8 round out and fix the bevel
that the mig "tack" filled.

man this is getting long winded -- sorry.

bottom line is: is a 3/8" gap pure madness on 3" pipe?

i started welding these flat on the table (1G position)
but couldn't get a consistent profile on the inside
penetration. (all they had was 3/32" filler and 3/32"
tungstens).

Next, I flipped them up on their flanges and welded
each joint in a 2G position and I got much more
consistent results with a great profile on the inside.

One satisfactory completed piece, with only the root
tig weld, on two joints (less than 20" of weld bead)
took me exactly 45 mins (including the grind time).

Q: is it my lack of experience with pipe welding? is
a 3/8" gap on this size pipe normal? in the end the
welds looked good, inside and out -- got a cupwalking
ripple pattern even though I had to float it (don't know
how to walk) because of the CHASM I had to cross.

there were no prints / specs / etc to follow.. just
"here's your pile of stuff -- weld it up for us"

thanks for stick'n through this. Smile
Tony


If I understand your description correctly the 3/8" round stock has been
placed IN the gap and forcing you to try to fill the now extremely oversize
gap space.

This seems time to call for the old weldor's joke.
'You had better order up some 'range rod' to fill those 'wide open spaces'.

IMHO, a 3/8" gap is "pure madness", (or at least inexperienced fitters).

An excessive gap (and IMHO this is far bigger than just excessive) will lead
to poor root weld quality as well as appearance and is likely to result in
failure of any QC & x-ray. This will of course be blamed on the weldor. It
will also lead to slow welding and the joint will probably be overheating
due to the slow forward progression. (It must be very challenging to
attempt this work without? a foot control) It will also consume a LOT more
rod than necessary. The weldor will also be blamed for being so slow and
for the poor weld appearance. The wide gap will also result in the cap
being too wide (and probably too high) and also taking too much time and
rod.

IMHO, it is up to the weldor to direct the fitter as to what gap/land he
requires. A 1/8" gap / 1/8" landing is most common but some (like me)
prefer a 3/32" gap / 3/32" landing, it depends on many factors like how good
the factory prep is and shipping damage and out of round or hi-low mismatch
of pipe or fitting dia.

Round stock is often placed in a pipe bevel so that the tack weld can be
placed up on the FACE of the bevel. If the round stock is too small then
the tack will spoil the land and if it is too big will spoil the top edge
and make for a poor looking cap and easily lead to an undercut cap edge.
The correct size 'bridge tack' will use round stock that will allow the tack
to be placed in the middle of the bevel so that it can be easily removed
without damage to the root land or to the top edge of the bevel. 1/4" or
3/16" is more common for bridge tacks but it depends on the pipe wall
thickness and bevel angle and shape.

I do not know of any weldors with your patience. I would have 'dragged up'
and made the fitters cut the joints apart and fit them properly. There is
no way that I would even attempt to fill a 3/8" gap, especially on 300 bench
pieces (600 welds?). In a field repair situation, I would cut the pipe
shorter, insert a pup and make two welds.

In this situation I suspect that the flanges are slip on type and if the
pipe has already been cut (and especially if welded to the pipe stub) then
the final part will now be 1/4" too short, or will have an unacceptable fit
inside the flange, (too much setback can cause turbulence and pipe wear).
IMHO, the elbow welds should have been made first, then the flange could be
fitted for final adjustment of size and square. It seems like the makings
of a real problem for somebody as the whole job may now be scrap. IMHO,
those experienced pipefitters (and weldors) that were too expensive to hire
will be starting to look like a bargain. I would respectfully question
whether anyone on this crew has the qualifications or experience for this
job.

Good luck, but be sure you don't carry the blame for this FU. IMHO, much
better to just drag up and go home.

Just my .02, Usenet advice is worth every penny you paid.
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SteveB
Posted: Tue Apr 29, 2008 8:18 pm
Guest
"outofstepper" <post@fononica.com> wrote in message
news:8218f5b8-d948-447a-8cbb-46eb5b5fd6f3@25g2000hsx.googlegroups.com...
Quote:
On Apr 29, 6:56 pm, "SteveB" <toquerville,utah@zionvistas> wrote:

What's your responsibility in this? If one of these leaks, is it going
to
be blamed on bad joint design, an excessive root, or YOU? Sounds like
you
got a bad design, questionable equipment, and not a lot of instructions.


In fact, thats why I'm posting here and not "working" Smile Took a few
days
to give their inspector a chance to look at them -- apparently he pops
in
with no real schedule.

Its hourly pay, not piece -- but I wanted to make a good impression.

Wanted to bring my own equip for day 2 but was told not to (guess the
pay's always the same and no point putting hours on my own tools?)
I did get real used to pulsed TIG -- but with this 4 foot gap I don't
think it
would've helped me any.

I'm told that these will be "Xray'd to 5%" -- I can't tell you what
that means..
maybe 5% of the whole lot?

Thanks for the input so far -- glad to know I'm not alone.

Evening all,
-Tony

Let me get the facts straight. You're not a full time weldor, but are
working on a project that is going to be x-rayed. Then are given materials
without a lot of directions or explanations.

I'd go to the powers that be and ask exactly what they want you to do, and
what the expectations are. No sense spending time and money on something
that is going to be unacceptable because of parameters not explained to you.
And no sense getting chewed on for not doing something right when you
weren't told anything about it in the first place. And maybe not getting
paid for pieces you've done that don't meet unstated expectations.

I'd get it all understood before I went any further. It's time to stop and
ask.

Steve
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outofstepper
Posted: Tue Apr 29, 2008 8:55 pm
Guest
Maybe I left out a critical piece of info ---
I'm out here in Europe (Italy) .. going on 6 years now with a
long over-due repatriation this summer.

Nothing really works quite 'right' out here -- its bizzarro world.

The kind of place where they hand you a tig torch that needs
the backcap duct taped because there aren't any more around.

Maybe the guy before me chewed the back off when he
saw what they wanted him to do.

Again, I agree with everyone here -- its day 2 now that I haven't
returned to their shop as I'm waiting for answers to just those
questions you've asked.

Wonder if my buddy isn't still grinding down that first cap.

Thanks again ... I just wanted to make sure I wasn't the crazy
one.

-Tony
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