Can galvanized fittings be used with black iron pipe?
Mikepier
weekend and found out they did not have anymore 1/2" Tee's in black
iron for my gas line. But they had galvanized 1/2" Tee's.
Can I mix the 2?
RicodJour
This is one of those questions that starts wars. Left coasters
generally can use galvanized, but I believe that is a different
galvanizing process for gas pipe than the standard galvanizing.
Something about the galvanizing flaking off or some such. East coast
generally has galvanized prohibited. Obviously your local code rules.
I would not mix galvanized and black iron directly, even if it's
allowed, as that accelerates corrosion. You'd have to use a
dielectric fitting.
Best thing is to visit a local plumbing supply house for such things.
They'll have stuff Lowes and Home Despot won't carry, and the guys
know far more than the guys in the aprons. On a side note, the local
big guy plumbing supply house, which I used to loathe going to as they
had major attitude and you had to be waited on (long lines and
attitude = I go elsewhere), changed over to a pick-your-own store set
up. Far superior. I'm sure they did it to trim superfluous counter
people and pickers, and make the store more user-friendly.
R
David Nebenzahl
> I would not mix galvanized and black iron directly, even if it's
> allowed, as that accelerates corrosion. You'd have to use a
> dielectric fitting.
Now *that* makes my BS meter twitch just a mite: why would there be
corrosion? Galvanized pipe is zinc over steel, so galvanized + steel
(black) should be no problem, right?
--
Comment on quaint Usenet customs, from Usenet:
To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.
HeyBub
> On 1/21/2011 9:58 PM RicodJour spake thus:
>
>> I would not mix galvanized and black iron directly, even if it's
>> allowed, as that accelerates corrosion. You'd have to use a
>> dielectric fitting.
>
> Now *that* makes my BS meter twitch just a mite: why would there be
> corrosion? Galvanized pipe is zinc over steel, so galvanized + steel
> (black) should be no problem, right?
To rephrase what you said, if zinc + steel = corrosion, than a galvanized
pipe should disintegrate just sitting on the rack.
SBH
"Mikepier" <mike...@optonline.net> wrote in message
news:e0edb9ea-edd1-41b7...@1g2000yqz.googlegroups.com...
Black pipe and galvanized pipe are the same material with just one
difference: galvanized pipe is coated with zinc to prevent the underlying
steel from corroding. Galvanized piping was commonly used in pipes that
carried drinking water--before the widespread use of copper piping and PEX
tubing. Black pipe was used in drain lines, heating piping and natural gas
piping. Black pipe can be used in lieu of galvanized pipe as long as the
piping system isn't for drinking water. Since both pipes are basically the
same material, they fit together with ease.
http://www.ehow.com/how_6816090_mix-black-pipe-galvanized-pipe.html
tra...@optonline.net
> "Mikepier" <mikep...@optonline.net> wrote in message
It's interesting that they worded it as "black pipe can be used in
lieu of
galvanized pipe...." and did not state that they are interchangeable,
ie
the other way around too. Though they seem to imply it. That
is the opposite substitution that the poster is asking about. And
like Rico
stated in the first reply, different areas have different rules
regarding the use
of galvanized pipe with gas.
I think from a practical standpoint, it's a nit. The theoretical
issue is that
natural gas can have contaminants which could react with the zinc,
form
flakes, which can come off and create problems. But, whether today's
gas even has that issue I don't know. Nor have I ever heard of it
actually
ocurring. IMO, you could mix the two if you had to, and it would be
fine,
but might not comply with local code. I'd just go find the black
fitting,
which are very common and should be easy to find.
I also think the ehow advice is incorrect in general anyway. First
they state
that the glavanizing is to prevent corrosion, then they say you can
substitute
black iron? Suppose the application is outside, exposed to the
weather,
for example. Galvanized won't rust and need to be painted, black
iron will.
Home Guy
I had to hook up a small electric water heater a few years ago and used
a combination of short-length galvinized and regular steel pipes and
tees near the tank, and used PEX feed lines to and from the tank.
In about 3 years the non-galvinized sections were very rust on the
outside, and really badly crudded-up on the inside, creating rusty water
if the hot water wasn't used for a few days (this is a small tank -
about 3 or 4 gallons). There was even some leaking of these pipes too.
I replaced everything with galvinized and no rust and no leaks for about
2-3 years now.
For a gas line, there is some water in natural gas - you're supposed to
put in a drop-trap line to catch the water before runs into your
appliance so the water can accumulate there. I'd be using galvinized
for that if it were me.
George
Depends on your gas utility. The giant bureaucratic mega company that
serves our area will not permit galvanized pipe or fittings.
Ed Pawlowski
"Home Guy" <Ho...@Guy.com> wrote
> For a gas line, there is some water in natural gas - you're supposed to
> put in a drop-trap line to catch the water before runs into your
> appliance so the water can accumulate there. I'd be using galvinized
> for that if it were me.
I'd not bother. I've seen installations that are 50 years old and no
problems with black pipe.
The Daring Dufas
The rules and inspectors in my area do not allow galvanized pipe use
on natural gas systems. I think in the uniform Southeast building code.
TDD
RicodJour
> On 1/21/2011 9:58 PM RicodJour spake thus:
>
> > I would not mix galvanized and black iron directly, even if it's
> > allowed, as that accelerates corrosion. You'd have to use a
> > dielectric fitting.
>
> Now *that* makes my BS meter twitch just a mite: why would there be
> corrosion? Galvanized pipe is zinc over steel, so galvanized + steel
> (black) should be no problem, right?
Time to recalibrate that meter, kimosabe. Zinc is used as a
sacrificial anode in boats for the very reason that it will corrode
first and protect the iron.
http://www.mikeholt.com/mojonewsarchive/All-HTML/HTML/Galvanic-Action~20010125.php
R
Tony Miklos
Exactly.
RicodJour
> On Jan 22, 8:31 am, "SBH" <m...@home.com> wrote:
> > "Mikepier" <mikep...@optonline.net> wrote in message
>
> > > weekend and found out they did not have anymore 1/2" Tee's in black
> > > iron for my gas line. But they had galvanized 1/2" Tee's.
> > > Can I mix the 2?
>
> > Black pipe and galvanized pipe are the same material with just one
> > difference: galvanized pipe is coated with zinc to prevent the underlying
> > steel from corroding. Galvanized piping was commonly used in pipes that
> > carried drinking water--before the widespread use of copper piping and PEX
> > tubing. Black pipe was used in drain lines, heating piping and natural gas
> > piping. Black pipe can be used in lieu of galvanized pipe as long as the
> > piping system isn't for drinking water. Since both pipes are basically the
> > same material, they fit together with ease.
>
> >http://www.ehow.com/how_6816090_mix-black-pipe-galvanized-pipe.html
>
> It's interesting that they worded it as "black pipe can be used in
> lieu of
> galvanized pipe...." and did not state that they are interchangeable,
> ie the other way around too. Though they seem to imply it. That
> is the opposite substitution that the poster is asking about. And
> like Rico
> stated in the first reply, different areas have different rules
> regarding the use of galvanized pipe with gas.
I have no personal experience with galvanized in a gas installation,
as I don't do them, and it's not allowed by the code around here. The
we(s)t coasters find it hilarious that the East coast codes often
prohibit it. I've heard that the galvanized used in gas installations
is different somehow, but again, no personal experience.
> I think from a practical standpoint, it's a nit. The theoretical
> issue is that
> natural gas can have contaminants which could react with the zinc, form
> flakes, which can come off and create problems. But, whether today's
> gas even has that issue I don't know. Nor have I ever heard of it actually
> ocurring. IMO, you could mix the two if you had to, and it would be fine,
> but might not comply with local code. I'd just go find the black fitting,
> which are very common and should be easy to find.
Like I said, the OP's question is one of those that start wars.
Everybody has anecdotal evidence (both ways) as 'proof', and the
difference on the subject in otherwise uniform codes makes it suspect
to many people.
> I also think the ehow advice is incorrect in general anyway. First they state
> that the glavanizing is to prevent corrosion, then they say you can substitute
> black iron? Suppose the application is outside, exposed to the weather,
> for example. Galvanized won't rust and need to be painted, black
> iron will.
eHow is often more like eWTF?
R
RicodJour
On second thought, you're right. It will - if you wait long enough.
R
RicodJour
On another note - doesn't anyone own a fucking boat? How the hell can
people work on houses without knowing about boats? The marine
environment is far more demanding and far more critical. The marine
industry has always been at the forefront of developing new methods
and materials. From owning and working on boats all of my life I've
learned about epoxy and fiberglass, rigging, pattern making, and all
sorts of other stuff which is directly applicable to building
construction and repair. If I wasn't allowed to use the knowledge
that I've garnered from boating, I'd feel like I was working with one
hand when I worked on a house. I don't use that knowledge on every
single task, but it's always in the arsenal waiting to be deployed.
R
hal...@aol.com
>
> - Show quoted text -
Galvanized isnt designed for Natural Gas.
The black iron pipe has closer tolerances.
galvanized is often welded up the side, rather than extruded ike black
iron.
dont use galvanized for gas lines
RicodJour
>
> Galvanized isn't designed for Natural Gas.
>
> The black iron pipe has closer tolerances.
>
> iron.
>
> don't use galvanized for gas lines
Bingo. I was waiting for someone to chime in with that. It surprises
me that people don't notice such things, and assume that all iron/
steel is the same.
I still have no clue what sort of galvanized pipe they use on the
other coast and how it differs, or if it differs, from galvanized pipe
in the Northeast. Anyone know?
R
Jon Danniken
ehow is the bottom of the bucket in ad-ridden spam sites; information on
ehow is written by idiots who think it's a GRQ scheme. You can pretty much
discount anyone linking to ehow as a complete net newbie, who chose ehow
because it came up first in a google search (they specifically design the
site so it comes up first).
There are a plethora of decent user-generated websites, forums, and even
commercial sites that are 100x better than ehow spam.
Jon
dpb
Much black pipe is welded as well (ERW, commonly, these days).
It's not the manufacturing process, per se, that determines the ASTM
Standard to which any given pipe will meet but the combination of
materials and manufacturing and quality control. Welded pipe may meet
or exceed a given seamless pipe of similar bore/schedule depending on
the intent and/or spec is was manufactured to. IOW, it isn't whether
it's welded or not matters, it's the Standard to which it was graded.
There's no difference in galvanized from one part of the country to the
other; the only more-or-less definitive study on its application w/
natural gas I've seen (not to say there isn't more; only this is only
one I've actually looked at) was done by PG&E who are, afaik, still west
coast... :)
It concluded that w/ current domestic gas the impurities that were the
initial concern weren't any longer but hedged its bets on the future w/
imports and particularly the possible/probable advent of large
quantities of import compressed/lng products.
It was dated sometime in the 90s iirc; I've no idea what might be
current Code or if any action was taken. Here in the barren middle
NG-producing part, local Code anyway still hasn't been modified other
than to accept the newer materials; galvanized is still generally not
seen for NG.
For a single fitting in a small line, I'd not worry about it back to the
OPs question altho I'm one that it would look out of place so I'd go get
a matching fitting just on that basis alone.
--
Bob F
The proper person to ask is the gas inspector for your area. Only they can give
you the right answer for your inspection after the work.
Here in Seattle, mixing galvanized is allowed. Where you live? I may depend on
the gas supply for your area. Apparently, different gas reacts differently with
galvanixed pipe.
dpb
...
> For a single fitting in a small line, I'd not worry about it back to the
> OPs question ...
I'll add that, of course, the obvious answer is to get the matching and
that what is kosher for the OP's area/Code is not at all the same thing
as whether I'd worry about the effects... :)
--
RicodJour
> RicodJour wrote:
> > On Jan 22, 1:01 pm, "hall...@aol.com" <hall...@aol.com> wrote:
> >> Galvanized isn't designed for Natural Gas.
>
> >> The black iron pipe has closer tolerances.
>
> >> galvanized is often welded up the side, rather than extruded like black
> >> iron.
>
> >> don't use galvanized for gas lines
>
> > Bingo. I was waiting for someone to chime in with that. It surprises
> > me that people don't notice such things, and assume that all iron/
> > steel is the same.
>
> > I still have no clue what sort of galvanized pipe they use on the
> > other coast and how it differs, or if it differs, from galvanized pipe
> > in the Northeast. Anyone know?
>
> Much black pipe is welded as well (ERW, commonly, these days).
>
> It's not the manufacturing process, per se, that determines the ASTM
> Standard to which any given pipe will meet but the combination of
> materials and manufacturing and quality control. Welded pipe may meet
> or exceed a given seamless pipe of similar bore/schedule depending on
> the intent and/or spec is was manufactured to. IOW, it isn't whether
> it's welded or not matters, it's the Standard to which it was graded.
The OP said he was shopping at Lowes. There is only one quality at
Lowes and they aim for the lowest selling price. What would you
deduce from that about the galvanized pipe they carry? That's a
rhetorical question.
R
dpb
...
> The OP said he was shopping at Lowes. There is only one quality at
> Lowes and they aim for the lowest selling price. What would you
> deduce from that about the galvanized pipe they carry?...
...
That there's at least a reasonable chance it's the same that he'd get a
stick from at any other local distributor including the "pro's" places...
--
cl...@snyder.on.ca
<rico...@worldemail.com> wrote:
>On Jan 22, 12:19 am, Mikepier <mikep...@optonline.net> wrote:
>> Was at Lowes tonight picking up stuff for hooking up my HW heater this
>> weekend and found out they did not have anymore 1/2" Tee's in black
>> iron for my gas line. But they had galvanized 1/2" Tee's.
>> Can I mix the 2?
>
>This is one of those questions that starts wars. Left coasters
>generally can use galvanized, but I believe that is a different
>galvanizing process for gas pipe than the standard galvanizing.
>Something about the galvanizing flaking off or some such. East coast
>generally has galvanized prohibited. Obviously your local code rules.
>
>I would not mix galvanized and black iron directly, even if it's
>allowed, as that accelerates corrosion. You'd have to use a
>dielectric fitting.
Pardon?????
Galvanize is Zinc applied to steal to prevent corrosion, and the layer
of zinc between two pieces of steel will NOT cause any corrosion.
And here in Ontario, far from the west coast, Galvanized piping is no
longer forbidden in gas piping.
>
>Best thing is to visit a local plumbing supply house for such things.
>They'll have stuff Lowes and Home Despot won't carry, and the guys
>know far more than the guys in the aprons. On a side note, the local
>big guy plumbing supply house, which I used to loathe going to as they
>had major attitude and you had to be waited on (long lines and
>attitude = I go elsewhere), changed over to a pick-your-own store set
>up. Far superior. I'm sure they did it to trim superfluous counter
>people and pickers, and make the store more user-friendly.
>
>R
I'd still recommend non-galvanized if possible - and most real
hardware and farm supply stores will still carry "black iron"
(maleable iron) fittings.
cl...@snyder.on.ca
YOur BS meter needs recalibrating. The ZINC may corrode, but that is
not an issue here. It is a very thin coating on one surface that is
beinf threaded to another (identical) surface. NOT an issue. Period.
cl...@snyder.on.ca
And a welded seam pipe is going to be an issue at less than 5 PSI
pressure in natural gas distribution, and not be an issue at 60+ psi
in a water system????
cl...@snyder.on.ca
There are only a few suppliers of both black and galvanized pipe in
Noth America, and a very large proportion of both is "imported -
mostly from China. Doesn't matter who you buy it from, or at what
price, the chances are very high you are buying the same product.
RicodJour
> On Sat, 22 Jan 2011, RicodJour <ricodj...@worldemail.com> wrote:
> >On Jan 22, 1:59 am, David Nebenzahl <nob...@but.us.chickens> wrote:
>
> >> Now *that* makes my BS meter twitch just a mite: why would there be
> >> corrosion? Galvanized pipe is zinc over steel, so galvanized + steel
> >> (black) should be no problem, right?
>
> >Time to recalibrate that meter, kimosabe. Zinc is used as a
> >sacrificial anode in boats for the very reason that it will corrode
> >first and protect the iron.
>
>
> YOur BS meter needs recalibrating. The ZINC may corrode, but that is
> not an issue here. It is a very thin coating on one surface that is
> beinf threaded to another (identical) surface. NOT an issue. Period.
Why would the zinc corroding not be an issue?
If you have a galvanized pipe and the coating is compromised in any
way, the corrosion will be concentrated at that point, right?
Why do gas companies and many codes prohibit using galvanized fittings
in gas lines?
Why do you feel that your apparently Pope-like-infallible opinion of
your opinion is at issue with those utility companies and AHJs?
You are familiar with sacrificial anodes, of course, and you do
understand that the more reactive metal will corrode more quickly in a
mixed metal situation, and you do know that not all gas is totally
pure, may contain water, that there are recommendations for having
traps to catch the water, but that the traps are not always present -
so why the blanket certainty over a very uncertain situation?
Oh, right - it's not your house.
Here's a possible repercussion that makes your opinion moot. A home
inspection. If a home inspector flags a galvanized fitting as being
against code, the homeowner will end up paying for it, and it will be
more than just the price of the fitting. The OP's theoretical attempt
at saving himself a trip to a more fully stocked supply house will
cost him more in the long run. Perhaps you're banking on the OP being
dead at that point, and it no longer being his concern, but I don't
take such a short-term view of the situation. :)
I am not saying that the potential problem with using a galvanized
fitting or whatever is necessarily a serious problem, nor is it
inevitable, simply that there is NO benefit to mixing galvanized and
black iron and it will raise concern, and increase the risk of a
problem, no matter how small that risk is.
So, to sum up, there is NO benefit - the galvanized costs more, it
will bother some people and some of those people are in a position to
tell you what to do with your house. So what exactly is your
reasoning that it's better to go with galvanized?
R
dpb
...
> Why do gas companies and many codes prohibit using galvanized fittings
> in gas lines?
Because there was some evidence that impurities in gas could lead to
interaction with galvanizing leading to some particulate contamination.
Once there, as with most Codes, it's much easier to retain than remove
restrictions whether they're still needed or not.
As noted above, PG&E did extensive study and determined it didn't seem
to be an issue of concern at the time; what that study didn't do was
make the decision as to whether to change policy or not. Whether that
happened or not subsequently, I don't know. But, the issue wasn't
related to this sidebar argument as to why galvanized was/is not used w/ NG.
--
HeyBub
>
> On another note - doesn't anyone own a fucking boat? How the hell can
> people work on houses without knowing about boats? The marine
> environment is far more demanding and far more critical. The marine
> industry has always been at the forefront of developing new methods
> and materials. From owning and working on boats all of my life I've
> learned about epoxy and fiberglass, rigging, pattern making, and all
> sorts of other stuff which is directly applicable to building
> construction and repair. If I wasn't allowed to use the knowledge
> that I've garnered from boating, I'd feel like I was working with one
> hand when I worked on a house. I don't use that knowledge on every
> single task, but it's always in the arsenal waiting to be deployed.
>
Because some people live in Nebraska?
JIMMIE
> Was at Lowes tonight picking up stuff for hooking up my HW heater this
> weekend and found out they did not have anymore 1/2" Tee's in black
> iron for my gas line. But they had galvanized 1/2" Tee's.
> Can I mix the 2?
first mistake, you were looking for plumbing at a big box store.
Jimmie
Vic Smith
<mike...@optonline.net> wrote:
>Was at Lowes tonight picking up stuff for hooking up my HW heater this
>weekend and found out they did not have anymore 1/2" Tee's in black
>iron for my gas line. But they had galvanized 1/2" Tee's.
>Can I mix the 2?
Just check the local code, and go by that.
See if it's all black pipe now.
If I knew black pipe was code, I'd use black pipe.
I put a galvanized gas pipe run in my first house in Chicago when I
working in the basement. Had just re-piped all the water and had
plenty of galvanized left over.
Sometime later a gas worker was in and spotted it right off.
Think it was an appliance guy when I bought a new dryer.
He said, "You do that?"
I said "Yep."
"Why'd you use galvanized?"
"That's what I had."
He could see my pipe bench.
Nothing more was said.
Always assumed he asked because galvanized was more expensive and not
necessary. Who knows.
I don't know what code is here, but I put a new HW tank a couple years
ago, and had to replace a gas nipple with a longer one.
Used galvanized, didn't think anything of it.
I just looked and see a lot of galvanized Tees and 90's on the gas
piping that were already there.
Now I'm pretty sure I'll never check the code.
--Vic
cl...@snyder.on.ca
<rico...@worldemail.com> wrote:
>On Jan 22, 3:38 pm, cl...@snyder.on.ca wrote:
>> On Sat, 22 Jan 2011, RicodJour <ricodj...@worldemail.com> wrote:
>> >On Jan 22, 1:59 am, David Nebenzahl <nob...@but.us.chickens> wrote:
>>
>> >> Now *that* makes my BS meter twitch just a mite: why would there be
>> >> corrosion? Galvanized pipe is zinc over steel, so galvanized + steel
>> >> (black) should be no problem, right?
>>
>> >Time to recalibrate that meter, kimosabe. Zinc is used as a
>> >sacrificial anode in boats for the very reason that it will corrode
>> >first and protect the iron.
>> >http://www.mikeholt.com/mojonewsarchive/All-HTML/HTML/Galvanic-Action...
>>
>>
>> YOur BS meter needs recalibrating. The ZINC may corrode, but that is
>> not an issue here. It is a very thin coating on one surface that is
>> beinf threaded to another (identical) surface. NOT an issue. Period.
>
>Why would the zinc corroding not be an issue?
The only zinc that could be an issue at all is inside the pipe or in
the joint, where it is protected - no oxygen available.
>If you have a galvanized pipe and the coating is compromised in any
>way, the corrosion will be concentrated at that point, right?
If it corrodes on the outside, so what? It's just like black iron.
>Why do gas companies and many codes prohibit using galvanized fittings
>in gas lines?
They don't (all) prohibit it. It can be used here. There are a couple
of galvanized fittings in my gasline, as well as brass valves.
>Why do you feel that your apparently Pope-like-infallible opinion of
>your opinion is at issue with those utility companies and AHJs?
It's not, as noted above.
>You are familiar with sacrificial anodes, of course, and you do
>understand that the more reactive metal will corrode more quickly in a
>mixed metal situation, and you do know that not all gas is totally
>pure, may contain water, that there are recommendations for having
>traps to catch the water, but that the traps are not always present -
>so why the blanket certainty over a very uncertain situation?
>Oh, right - it's not your house.
Code REQUIRES the drops - and it is NOT for water. It is to allow any
particulates to drop out at the LAST bend before entering the
appliance. The particles could block a jet - and that would cause
problems. That particle COULD be rust, or flaked off zinc from inside
either black iron or galvanized pipe.
Water in the gas would be a reason to REQUIRE zinc, not to ban it.
>
>Here's a possible repercussion that makes your opinion moot. A home
>inspection. If a home inspector flags a galvanized fitting as being
>against code, the homeowner will end up paying for it, and it will be
>more than just the price of the fitting. The OP's theoretical attempt
>at saving himself a trip to a more fully stocked supply house will
>cost him more in the long run. Perhaps you're banking on the OP being
>dead at that point, and it no longer being his concern, but I don't
>take such a short-term view of the situation. :)
Not at all. As I said, where I live the prohibition against galvanized
fittings has been removed, for quite a few years now.
If you have the REQUIRED drop trap any possible particulates will be
caught - and the probability/possibility of a galvanized fitting ot
pipe causing a problem is no higher than that of black pipe. The
prohibition against Galvanized goes back to "producer gas" or "coal
gas" which was the common municipal gas supply for many years,
particularly in the east.
>
>I am not saying that the potential problem with using a galvanized
>fitting or whatever is necessarily a serious problem, nor is it
>inevitable, simply that there is NO benefit to mixing galvanized and
>black iron and it will raise concern, and increase the risk of a
>problem, no matter how small that risk is.
>
>So, to sum up, there is NO benefit - the galvanized costs more, it
>will bother some people and some of those people are in a position to
>tell you what to do with your house. So what exactly is your
>reasoning that it's better to go with galvanized?
First of all, I NEVER said it was BETTER to go with galvanized. I just
said if he could not get a black fitting there was no HARM is using
galvanized. I even said any REAL hardware store or farm supply would
have the required fitting.As in the black iron, or maleable iron
fitting.
You are just being arguementative, and your reading comprehension is
not up to par.
>
>R
Bob F
My understanding is that sulphur or something in some gas can cause problems
with galvanized piping, so if the local supply has it, galvanized may not be
allowed. Part of the problem may relate to the zinc flaking off the iron, and
plugging orifaces. The drop tube below the "T" to the burner is there to catch
such debris, I believe.
David Nebenzahl
> On Jan 22, 3:38 pm, cl...@snyder.on.ca wrote:
>
>> On Sat, 22 Jan 2011, RicodJour <ricodj...@worldemail.com> wrote:
>>
>>> On Jan 22, 1:59 am, David Nebenzahl <nob...@but.us.chickens>
>>> wrote:
>>>
>>>> Now *that* makes my BS meter twitch just a mite: why would
>>>> there be corrosion? Galvanized pipe is zinc over steel, so
>>>> galvanized + steel (black) should be no problem, right?
>>>
>>> Time to recalibrate that meter, kimosabe. Zinc is used as a
>>> sacrificial anode in boats for the very reason that it will
>>> corrode first and protect the iron.
>>> http://www.mikeholt.com/mojonewsarchive/All-HTML/HTML/Galvanic-Action...
>>
>> YOur BS meter needs recalibrating. The ZINC may corrode, but that
>> is not an issue here. It is a very thin coating on one surface that
>> is beinf threaded to another (identical) surface. NOT an issue.
>> Period.
>
> Why would the zinc corroding not be an issue?
> If you have a galvanized pipe and the coating is compromised in any
> way, the corrosion will be concentrated at that point, right?
This still makes no sense to me. (And just for the record, whenever I've
plumbed for gas I've used black pipe, not galvanized.)
I mean, with black pipe, the entire goddamned pipe and every fitting is
subject to corrosion, right? Except for the mill scale, or whatever
constitutes the "black" on black pipe, it's completely unprotected.
That's why we use galvanized for water. So if you use a galvanized
fitting on a run of black pipe, it sure as hell is not going to corrode
any faster than the rest of the pipe, so why sweat it *on that basis*?
There may be other reasons not to use galvanized with gas lines: all the
pros I've talked to about this lately tell me it makes no difference.
Nonetheless, most people still use black for gas.
--
Comment on quaint Usenet customs, from Usenet:
To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.
David Nebenzahl
> tra...@optonline.net wrote:
>
>> I also think the ehow advice is incorrect in general anyway.
>
> ehow is the bottom of the bucket in ad-ridden spam sites; information on
> ehow is written by idiots who think it's a GRQ scheme. You can pretty much
> discount anyone linking to ehow as a complete net newbie, who chose ehow
> because it came up first in a google search (they specifically design the
> site so it comes up first).
As I recall, eHow is basically just a web "scraper" that copies content
from Wikipedia (another notoriously unreliable source) and republishes
it, confirming what Jon just wrote.
David Nebenzahl
> My understanding is that sulphur or something in some gas can cause problems
> with galvanized piping, so if the local supply has it, galvanized may not be
> allowed. Part of the problem may relate to the zinc flaking off the iron, and
> plugging orifaces. The drop tube below the "T" to the burner is there to catch
> such debris, I believe.
Y'know, this business of how gas might *possibly* cause the coating to
"flake off" of galvanized piping has been brought up several times in
this thread. But nobody has provided any evidence for this, not even
anecdotal. Certainly no articles in scientific journals or the like.
So until I see such evidence, I'm going to write this off as basically
urban legend, from the dim, dark past of gas companies who didn't really
know *what* was happening.
But I still use black pipe only on gas, just from force of habit ...
RicodJour
>
> You are just being arguementative, and your reading comprehension is
> not up to par.
In my reply to the OP's question, the first reply in this thread, I
wrote, "This is one of those questions that starts wars. Left
coasters generally can use galvanized, but I believe that is a
different galvanizing process for gas pipe than the standard
galvanizing. Something about the galvanizing flaking off or some
such. East coast generally has galvanized prohibited. Obviously your
local code rules. " Is that what you are arguing about?
I'll tell you what, I'll get the local gas utility company, and the
local municipalities that are within the OP's and my area (we're about
15 or 20 miles from each other, and there might be five or six
different individual codes for the municipalities between the two of
us), to change their codes if they don't accept galvanized pipe, just
based on the say so of some guy in Canada. Will that be acceptable to
you?
I'm answering the OP's question and you're arguing how many angels can
dance on the head of a pin. Big help.
R
RicodJour
> On 1/22/2011 3:38 PM Bob F spake thus:
>
> > My understanding is that sulphur or something in some gas can cause problems
> > with galvanized piping, so if the local supply has it, galvanized may not be
> > allowed. Part of the problem may relate to the zinc flaking off the iron, and
> > plugging orifaces. The drop tube below the "T" to the burner is there to catch
> > such debris, I believe.
>
> Y'know, this business of how gas might *possibly* cause the coating to
> "flake off" of galvanized piping has been brought up several times in
> this thread. But nobody has provided any evidence for this, not even
> anecdotal. Certainly no articles in scientific journals or the like.
I've been looking for more information as well, and I have to agree
with you. There's a lot of conjecture and a lot of argument about
it. Like I've said, this topic starts wars. Maybe it's like a
plumbing WMD - wars with no foundation!
> So until I see such evidence, I'm going to write this off as basically
> urban legend, from the dim, dark past of gas companies who didn't really
> know *what* was happening.
>
> But I still use black pipe only on gas, just from force of habit ...
I recently replaced part of the 1.5" black iron condensate return line
on our one-pipe steam system. The pipe was original to the house and
about 80 years old. A few years back we had a leak on, you guessed
it, the night before Christmas Eve. It had rusted through at the
first vertical to horizontal transition on its return run. The
outside of the pipe was quite rusted in places, and, because of that
leak, I figured the pipe was just about done and I wasn't going to
wait for another leak. When I busted off the first fitting and
removed that first section of pipe, I was quite surprised to see the
condition of the inside of the pipe. It looked almost new. There was
a thin, uniform black layer coating the inside, and other than that
was remarkably clean. There was no rust in the pipe or the fittings.
The fitting that leaked was buried inside a wall just about the
basement slab and had rusted from the outside in. The old concrete
foundation wall had been compromised by water intrustion over the
years and what was essentially sand had buried the pipe and kept the
outside of the pipe wet enough to rust at an accelerated rate, but
there wasn't enough water coming through the foundation to show up
inside the living space.
I discovered some new-found respect for black iron pipe from that
abbreviated replace-it-all project attempt - there was no need. In
the same or less time, galvanized pipe of the same size has had to be
replaced at several places in the house. This is backwards to what
everybody 'knows' -galvanized pipe will last longer than black iron -
but I've seen it firsthand. I still don't tell people to go against
code and buy the cheaper black iron pipe if code calls for
galvanized. When I replaced the section of pipe I had cut out, I
replaced it with black iron. I'll let you know in 80 years how it's
held up. ;)
The codes around here are messed up. Until very recently there was
one nearby village that required 3/4" plywood sheathing on the walls
and roof, cast iron subsurface rainwater drainage lines, BX electrical
cable (say what?!), two layers of 1/2" drywall laid at right angles
with both layers taped, and slate roofs. Only when the prices of
things got so ridiculous, and the homeowner's started listening to the
contractors telling them that the code did not benefit them in any way
and only wasted large amounts of money, did the village start
modifying their code.
But who tells a gas company what to do?
R
Colbyt
"Mikepier" <mike...@optonline.net> wrote in message
news:e0edb9ea-edd1-41b7...@1g2000yqz.googlegroups.com...
> Was at Lowes tonight picking up stuff for hooking up my HW heater this
> weekend and found out they did not have anymore 1/2" Tee's in black
> iron for my gas line. But they had galvanized 1/2" Tee's.
> Can I mix the 2?
Local codes rule.
At one time it was prohibited in this area and now it is fine.
If you don't know the local code, I would find a black fitting somewhere.
I have used them in a pinch in the past and never experienced any of the
dour predictions I have seen expressed in this thread. I should add that I
own the same houses now that I did 20 years or more ago.
--
Colbyt
Please come visit http://www.househomerepair.com
Harry K
> On 1/21/2011 9:58 PM RicodJour spake thus:
>
> > I would not mix galvanized and black iron directly, even if it's
> > allowed, as that accelerates corrosion. You'd have to use a
> > dielectric fitting.
>
> corrosion? Galvanized pipe is zinc over steel, so galvanized + steel
> (black) should be no problem, right?
>
> Comment on quaint Usenet customs, from Usenet:
>
> To me, the *plonk...* reminds me of the old man at the public hearing
> who stands to make his point, then removes his hearing aid as a sign
> that he is not going to hear any rebuttals.
To add to that. The "zinc" on the galvanised never touches the "black
iron". Threading removes the zinc plating in that area and the
fittings never screw together far enough for the zinc to touch the
unplated pipe/fitting.
Harry K
DD_BobK
> Was at Lowes tonight picking up stuff for hooking up my HW heater this
> weekend and found out they did not have anymore 1/2" Tee's in black
> iron for my gas line. But they had galvanized 1/2" Tee's.
> Can I mix the 2?
I asked this question of my mechanical engineering mentor nearly ~35
years ago.
He's long gone & I have mixed installations that has been in service
for over 30 years.
He's comment to me back in the 70's was........
"The myth that natural gas causes galvanizing to flake off is an old
wives tale that has debunked by testing, go ahead and use it"
Here is a link to pretty detailed thread on the subject, including
cites from the IRC.
http://www4.iccsafe.org/cgi-bin/ultimatebb.cgi?ubb=print_topic;f=2;t=002632
a couple guys go back & forth but I'm putting my money on the IRC,
posts in the cited thread by dsjtecserv & my mentor.
He had YEARS of industrial mechanical engineering experience,
including being the chief engineer on design & construction of a
natural gas to fertilizer plant.
YMMV but has been pretty good so far :)
cheers
Bob
tra...@optonline.net
>
> - Show quoted text -
To the above I would add that the comparison to the boat use of zinc
as a
sacrificial anode is invalid, unless the pipe in question is being
used in
an environment where it's EXPOSED TO AN ELECTROLYTE. The
electrolyte essentially completes a circuit that allows current to
flow. In
the case of boats, that electrolyte is water, or even worse, salt
water.
With the boat, you have sacraficial zinc plates electrically bonded to
the
underwater metal parts, ie shafts, props, struts, etc. The circuit
looks
like two different metals, ie bronze and zinc, sitting in a beaker of
salt
water. Very similar to the experiment kids can do, using a lemon, a
dime, and a penny to make a battery. As the current flow, the zinc
erodes and slowly disappears.
With galvanized pipe installed on a gas line indoors, you don't have
an
electrolyte. If it were buried, then you could have an issue. But
buried
you have an issue with black steel too. I think it's still being
allowed in
some areas. But it's supposed to be coated and or wrapped with tape
to prevent corrosion. A process that is far from perfect. I've
seen
black steel pipe fail underground in as little as five years. It
looked
like swiss cheese, hard to believe. But it was obvious what had
ocurred. You could see where the installers had used black pipe and
then poured the tar like coating over the top of it after it was
installed
in the trench. The bottom portion did not get coated and that is
where the failure ocurrred. I remember at the time, mid 90s, we had
the gas company involved in recommending what to do at a 120
unit condo. At that time even they were undecided which was better
for that application, either black pipe correctly installed or
galvanized.
Today, for corrosion issues, plastic is now widely used underground.
Over the years gas companies have looked at ALL the issues, including
not only what the pipe is carrying, but where it is being used. The
only
potential problem with galvanized that I've ever seen documented in
any way is that which DPB brought up, which is the
concern that certain impurities in the gas could lead to the zinc
flaking
off and ultimately clogging orifices, etc. I don't believe it was
ever
an issue of the pipe failing, leaking, etc. If galvanic corrosion
were a
real issue with gas pipe in an application inside a house, the gas
companies that allow it would be pretty stupid, no? As would the fire
rating, safety, insurance companies, etc.
Art Todesco
> On Jan 21, 9:19 pm, Mikepier<mikep...@optonline.net> wrote:
>> Was at Lowes tonight picking up stuff for hooking up my HW heater this
>> weekend and found out they did not have anymore 1/2" Tee's in black
>> iron for my gas line. But they had galvanized 1/2" Tee's.
>> Can I mix the 2?
>
> I asked this question of my mechanical engineering mentor nearly ~35
> years ago.
> for over 30 years.
>
> He's comment to me back in the 70's was........
>
> "The myth that natural gas causes galvanizing to flake off is an old
> wives tale that has debunked by testing, go ahead and use it"
>
> Here is a link to pretty detailed thread on the subject, including
> cites from the IRC.
>
> http://www4.iccsafe.org/cgi-bin/ultimatebb.cgi?ubb=print_topic;f=2;t=002632
>
> posts in the cited thread by dsjtecserv& my mentor.
> He had YEARS of industrial mechanical engineering experience,
> natural gas to fertilizer plant.
>
> YMMV but has been pretty good so far :)
>
> cheers
> Bob
black iron pipe is used for gas because, when tightening a joint,
the pipes grind into one another making a tighter seal. I don't
know one way or another .... that's just what I was told. I've
heard all the other "tales". The gas (propane) in my new house is
neither. It's a corrugated flex line, covered with yellow plasticy
rubbery stuff ... looks like yellow heat shrink tubing.
George
was where the (cracked) plastic coated now rusted through black pipe
emerged from the ground into the valve.
I called the gas company and they were there within minutes. There were
at least 6 trucks (including one with a backhoe on a trailer) from the
gas company out on the street. I asked what that was about and he said
everyone who hears the radio broadcast of a gas leak that is nearby
needs to drop what they are doing and head to the location. That is
because they got dinged a few months back during a structure fire when
it took them hours to respond.
They have a specific prohibition against galvanized pipe. The foreman
said they would replace everything on the outside. They ran a new
plastic lateral from the street. Another guy carried in a complete new
riser, valve, regulator and meter saddle assembly. The line side had a
90 degree long sweep *galvanized steel* elbow. The plastic adapter was
attached on one side and the shutoff on the other side.
Gas companies seem to have their own tradition about being impossible to
deal with. I own some rentals. The current gas company is a huge
outfit. They purchased the regional provider that served our area. One
tenant announced they were moving out so something told me to call the
gas company and verify that the service would transfer to my name as it
did previously. I called and they said they did not know who I was. I
provided them with the meter numbers and the accounts that were
generated on previous occasions. I also provided them with the account
for our house. They said since they didn't know me I would need to fill
out some form and fax (who uses fax) it to them. They said it would take
two weeks to process? I asked if I could stop by their office and they
said they no longer had offices open to the public. I asked if I could
fill out the form on their web site and they said they don't have that
available. Since the tenant was moving out in a few days I persisted and
ended up talking to some VP who insisted it was the fault of the
customer service person who answered my call.
I asked him to describe what authority the customer service person had
to solve the problem and he said they had none. I then suggested he
needed to look in the mirror if he wanted to see the problem.
RicodJour
I can not argue with any of that, even though it does poke large holes
in my argument.
On the plus side - I did get to get in a nice plug for the marine
industry. ;)
We've agreed on the following:
- that the IRC and many other codes allow mixing galvanized and black
iron pipe in distribution lines
- that there is little likelihood of there being any problems by doing
so
- that some local codes and gas utilities prohibit using galvanized
pipe
- that it is mandatory that people contemplating using galvanized pipe
in gas installations check with their gas utility and/or local code to
see if it is permitted.
Now, how do we erase all of the extraneous back-and-forth on the topic
on the Internet so people will have a clear, simple grasp of the
issues?
R
The Daring Dufas
How can something so simple become so complex? :-)
TDD
RicodJour
wrote:
Human nature...? Just bring up the subject of helmets on a cycling
newsgroup. Everyone is 100% right, adamant about it, and nobody
agrees.
R
Sjouke Burry
a zillion different sets of rules?
cl...@snyder.on.ca
More or less true - but "some" galvanized fittings appear to have
zinc in the female threaded portion.
Not with hot dip galvanizing, for sure - but in "bright zinc"
"galvanizing".
This does not change the fact that the zinc is NOT a corrosion risk.
DD_BobK
Use Google. Erase.......
it is similar to Google.Takeback (what you use when you want retrieve
an email or posting that you wish you hadn't sent.)
cheers
Bob
dpb
...
>> Now, how do we erase all of the extraneous back-and-forth on the topic
>> on the Internet so people will have a clear, simple grasp of the
>> issues?
>>
>> R
>
> Use Google. Erase.......
>
> it is similar to Google.Takeback (what you use when you want retrieve
> an email or posting that you wish you hadn't sent.)
...
Can't help; once a posting hits usenet, it's gone. Virtually no servers
honor cancel messages.
--
RicodJour
>
> it is similar to Google.Takeback (what you use when you want retrieve
> an email or posting that you wish you hadn't sent.)
Would that it were so. That only works with Google posting, right?
I'm talking about all of the forums and sources out there where this
topic comes up repeatedly and the same information gets batted about.
Since we've 'solved' it, we should save other people from having to
wade through the extraneous and misleading information. Maybe post a
Wikipedia article and just point back to that whenever it comes up
here? Post the Wiki link on those other forums?
R
Oren
>This does not change the fact that the zinc is NOT a corrosion risk.
My black gas pipe(s) have a brass (yellow knob) 1/4 turn valve. Made
of brass, requiring zinc in the making, no? Then I just go to Casa
Depot and get a connection kit for the gas appliances. Stove-top,
clothes dryer and water heater. All kinds of metal used for all the
connections.
To much zinc in the making of brass might cause a brass fitting (PEX
connector) to leak.
RicodJour
>
> To much zinc in the making of brass might cause a brass fitting (PEX
> connector) to leak.
Why in the world would the Chinese use too much zinc in the copper
alloy? That would be unethical and greedy. Could never happen. ;)
R
David Nebenzahl
[massive snipola]
> Now, how do we erase all of the extraneous back-and-forth on the topic
> on the Internet so people will have a clear, simple grasp of the
> issues?
Like they say, good luck with that!
David Nebenzahl
> On 1/23/2011 2:24 AM, DD_BobK wrote:
>
>> On Jan 21, 9:19 pm, Mikepier<mikep...@optonline.net> wrote:
>>
>>> Was at Lowes tonight picking up stuff for hooking up my HW heater
>>> this weekend and found out they did not have anymore 1/2" Tee's
>>> in black iron for my gas line. But they had galvanized 1/2"
>>> Tee's. Can I mix the 2?
>>
>> I asked this question of my mechanical engineering mentor nearly
>> ~35 years ago. He's long gone& I have mixed installations that has
>> been in service for over 30 years.
>>
>> He's comment to me back in the 70's was........
>>
>> "The myth that natural gas causes galvanizing to flake off is an
>> old wives tale that has debunked by testing, go ahead and use it"
>>
>> Here is a link to pretty detailed thread on the subject, including
>> cites from the IRC.
>>
>> http://www4.iccsafe.org/cgi-bin/ultimatebb.cgi?ubb=print_topic;f=2;t=002632
>>
>> a couple guys go back& forth but I'm putting my money on the IRC,
>> posts in the cited thread by dsjtecserv& my mentor. He had YEARS
>> of industrial mechanical engineering experience, including being
>> the chief engineer on design& construction of a natural gas to
>> fertilizer plant.
>>
>> YMMV but has been pretty good so far :)
>
> Well, when I was a kid in the 50s and 60s, someone told me that
> black iron pipe is used for gas because, when tightening a joint,
> the pipes grind into one another making a tighter seal. I don't
> know one way or another .... that's just what I was told. I've
> heard all the other "tales".
What you heard was essentially correct. When you tighten a pipe fitting
with any kind of metal pipe--black iron, galvanized, brass, bronze,
etc., both threads deform--in other words, get squished--enough to
remove almost all gaps between them. That's how pipes get sealed. (What
few microscopic gaps may be left are filled by Teflon tape or pipe
thread compound.)
Stormin Mormon
--
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"RicodJour" <rico...@worldemail.com> wrote in message
news:e4d2d3de-87ac-4574...@o14g2000yqe.googlegroups.com...
George
villiewe
Simple: I assumed the black iron was so you could tell which lines were gas
while galvanized was water.
When I had this house inspected 41 years ago before buying, he suggested I ask
the owner was was the purpose of the galvanized iron going to the attic! I
paid him anyway!
--
for full context, visit https://www.homeownershub.com/maintenance/can-galvanized-fittings-be-used-with-black-iron-pipe-616549-.htm