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undoing gas line unions

updated sun 26 aug 01

 

Robert and Mary Ann Sparacin on fri 24 aug 01


Dear Jennifer,

I do not know what kind of heat the threads are subject to. If the the compound
gets hard or gummy from the heat between changes, it might make it difficult to
reassemble the next time, and in the worse case, possibly giving a false positive
should someone fail to clean it properly ( a pain to do) and then tries to tighten
up... and in the worst case, damaging the threads, possibly stripping them out from
excessive pressure, or because they were not easy to lined up before pressure was
applied. ( cross threaded)... damaged threads can loosen up later with vibration..
Although this does not seem to be the case here, I have also seen people (not very good
mechanics) think that the seal is in the threads, and apply Teflon pipe dope, or worse,
to the threads, which may harden in time (even though it is not supposed to, especially
with steam pipes). I raise this point because gas can be explosive, and I feel it
proper to show concern that the threads are smooth acting, not galled, cross threaded
(has happened) gummed up, etc., so a good seal is made. Most mechanics with an
awareness can avoid problems..( in new brass fittings check for holes from sand
castings, for cracks, for defective seals, other defects, etc..... just don't blindly
reassemble or install new fittings.). Also I am writing this with the concern that
someone with less understanding than you, might read this and apply something which may
become a problem later, because of possible temperature conditions at the site, and not
understand how the seal is made... which is why people put pipe dope on the threads...
which is completely different form putting a non seizing lubrication on the threads. I
suggest that you use a commercial product which is designated for the job, an
appropriate never-seize product is cheap enough. Ask a dealer for what would be best.
When you are working with gas in an enclosed area, I think that you should USE THE
RIGHT THING.(which also means the right wrench, not Pliers!..I've seen that also)

RJS



Jennifer F Boyer wrote:

> Hi Robert,
> Yeah, I understand about the seal faces making the tight seal,
> so why would compound in the threads compromise the seal if the
> seal faces are clean? Just wondering
> Jennifer, burners all over the floor while we get this resolved....
>
> Robert and Mary Ann Sparacin wrote:
> >
> > Dear Jennifer R Boyer,
> >
> > You might try one of the never seize compounds available in a good auto or
> > plumbing store. I believe that some are rate to withstand 1500 degrees F..
> > Remember, that the threads of a standard union do not make the seal, they only
> > press the seals faces together to make a leak free union. For that reason, the
> > threads of the union must be free enough to efficiently draw the two seal faces
> > together.
> >
> > RJS
> >
> > Jennifer F Boyer wrote:
> >
> > > Geez,
> > > I hope I can say this is plain English:
> > > I have pressure(? w/ a collar) unions in my gas lines for taking
> > > off my propane venturi burners for cleaning. They were hard to
> > > undo this last time: I hadn't cleaned my burners in a year(!).
> > > I'm putting them all back together, and I wonder if I can smear
> > > vaseline or something on the threads to make it easier to get
> > > them undone next time. Any opinions? I vaguely remember that I
> > > can't use tape on this kind of fitting....
> > > Jennifer, wondering how much more iron scale I can bang out of
> > > these 25 year old burners before they just disappear one day.......;-)
> > >
> > > --
> > > ~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
> > > Jennifer Boyer mailto:jboyer@adelphia.net
> > > Thistle Hill Pottery
> > > 95 Powder Horn Glen Rd
> > > Montpelier, VT 05602 USA
> > > 802-223-8926
> > > http://www.thistlehillpottery.com/
> > >
> > > Never pass on an email warning without checking out this site
> > > for web hoaxes and junk:
> > > http://urbanlegends.about.com/science/urbanlegends/cs/nethoaxes/index.htm
> > > ~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
> > >
> > > ______________________________________________________________________________
> > > Send postings to clayart@lsv.ceramics.org
> > >
> > > You may look at the archives for the list or change your subscription
> > > settings from http://www.ceramics.org/clayart/
> > >
> > > Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
> >
> > ______________________________________________________________________________
> > Send postings to clayart@lsv.ceramics.org
> >
> > You may look at the archives for the list or change your subscription
> > settings from http://www.ceramics.org/clayart/
> >
> > Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
>
> --
> ~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
> Jennifer Boyer mailto:jboyer@adelphia.net
> Thistle Hill Pottery
> 95 Powder Horn Glen Rd
> Montpelier, VT 05602 USA
> 802-223-8926
> http://www.thistlehillpottery.com/
>
> Never pass on an email warning without checking out this site
> for web hoaxes and junk:
> http://urbanlegends.about.com/science/urbanlegends/cs/nethoaxes/index.htm
> ~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.

Jennifer F Boyer on fri 24 aug 01


Geez,
I hope I can say this is plain English:
I have pressure(? w/ a collar) unions in my gas lines for taking
off my propane venturi burners for cleaning. They were hard to
undo this last time: I hadn't cleaned my burners in a year(!).
I'm putting them all back together, and I wonder if I can smear
vaseline or something on the threads to make it easier to get
them undone next time. Any opinions? I vaguely remember that I
can't use tape on this kind of fitting....
Jennifer, wondering how much more iron scale I can bang out of
these 25 year old burners before they just disappear one day.......;-)

--
~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
Jennifer Boyer mailto:jboyer@adelphia.net
Thistle Hill Pottery
95 Powder Horn Glen Rd
Montpelier, VT 05602 USA
802-223-8926
http://www.thistlehillpottery.com/

Never pass on an email warning without checking out this site
for web hoaxes and junk:
http://urbanlegends.about.com/science/urbanlegends/cs/nethoaxes/index.htm
~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*

Robert and Mary Ann Sparacin on fri 24 aug 01


Dear Jennifer R Boyer,

You might try one of the never seize compounds available in a good auto or
plumbing store. I believe that some are rate to withstand 1500 degrees F..
Remember, that the threads of a standard union do not make the seal, they only
press the seals faces together to make a leak free union. For that reason, the
threads of the union must be free enough to efficiently draw the two seal faces
together.

RJS

Jennifer F Boyer wrote:

> Geez,
> I hope I can say this is plain English:
> I have pressure(? w/ a collar) unions in my gas lines for taking
> off my propane venturi burners for cleaning. They were hard to
> undo this last time: I hadn't cleaned my burners in a year(!).
> I'm putting them all back together, and I wonder if I can smear
> vaseline or something on the threads to make it easier to get
> them undone next time. Any opinions? I vaguely remember that I
> can't use tape on this kind of fitting....
> Jennifer, wondering how much more iron scale I can bang out of
> these 25 year old burners before they just disappear one day.......;-)
>
> --
> ~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
> Jennifer Boyer mailto:jboyer@adelphia.net
> Thistle Hill Pottery
> 95 Powder Horn Glen Rd
> Montpelier, VT 05602 USA
> 802-223-8926
> http://www.thistlehillpottery.com/
>
> Never pass on an email warning without checking out this site
> for web hoaxes and junk:
> http://urbanlegends.about.com/science/urbanlegends/cs/nethoaxes/index.htm
> ~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.

Howard Scoggins on fri 24 aug 01


Jennifer--

An old boilermaker's trick: Paint the threads with Milk of Magnesia, =
right out of the bottle. Screw 'em on wet and=20
you'll never have a heat-seized joint again.

Howard Scoggins

Jennifer F Boyer on fri 24 aug 01


Hi Howard. This works for the kind seal that I use, which Robert
described below?

<union do not make the seal, they only
press the seals faces together to make a leak
free union. For that reason, the
threads of the union must be free enough to
efficiently draw the two seal faces
together.>>

Jennifer

Howard Scoggins wrote:
>
> Jennifer--
>
> An old boilermaker's trick: Paint the threads with Milk of Magnesia, =
> right out of the bottle. Screw 'em on wet and=20
> you'll never have a heat-seized joint again.
>
> Howard Scoggins
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.

--
~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
Jennifer Boyer mailto:jboyer@adelphia.net
Thistle Hill Pottery
95 Powder Horn Glen Rd
Montpelier, VT 05602 USA
802-223-8926
http://www.thistlehillpottery.com/

Never pass on an email warning without checking out this site
for web hoaxes and junk:
http://urbanlegends.about.com/science/urbanlegends/cs/nethoaxes/index.htm
~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*

Jennifer F Boyer on fri 24 aug 01


Hi Robert,
Yeah, I understand about the seal faces making the tight seal,
so why would compound in the threads compromise the seal if the
seal faces are clean? Just wondering
Jennifer, burners all over the floor while we get this resolved....

Robert and Mary Ann Sparacin wrote:
>
> Dear Jennifer R Boyer,
>
> You might try one of the never seize compounds available in a good auto or
> plumbing store. I believe that some are rate to withstand 1500 degrees F..
> Remember, that the threads of a standard union do not make the seal, they only
> press the seals faces together to make a leak free union. For that reason, the
> threads of the union must be free enough to efficiently draw the two seal faces
> together.
>
> RJS
>
> Jennifer F Boyer wrote:
>
> > Geez,
> > I hope I can say this is plain English:
> > I have pressure(? w/ a collar) unions in my gas lines for taking
> > off my propane venturi burners for cleaning. They were hard to
> > undo this last time: I hadn't cleaned my burners in a year(!).
> > I'm putting them all back together, and I wonder if I can smear
> > vaseline or something on the threads to make it easier to get
> > them undone next time. Any opinions? I vaguely remember that I
> > can't use tape on this kind of fitting....
> > Jennifer, wondering how much more iron scale I can bang out of
> > these 25 year old burners before they just disappear one day.......;-)
> >
> > --
> > ~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
> > Jennifer Boyer mailto:jboyer@adelphia.net
> > Thistle Hill Pottery
> > 95 Powder Horn Glen Rd
> > Montpelier, VT 05602 USA
> > 802-223-8926
> > http://www.thistlehillpottery.com/
> >
> > Never pass on an email warning without checking out this site
> > for web hoaxes and junk:
> > http://urbanlegends.about.com/science/urbanlegends/cs/nethoaxes/index.htm
> > ~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
> >
> > ______________________________________________________________________________
> > Send postings to clayart@lsv.ceramics.org
> >
> > You may look at the archives for the list or change your subscription
> > settings from http://www.ceramics.org/clayart/
> >
> > Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.

--
~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
Jennifer Boyer mailto:jboyer@adelphia.net
Thistle Hill Pottery
95 Powder Horn Glen Rd
Montpelier, VT 05602 USA
802-223-8926
http://www.thistlehillpottery.com/

Never pass on an email warning without checking out this site
for web hoaxes and junk:
http://urbanlegends.about.com/science/urbanlegends/cs/nethoaxes/index.htm
~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*

vince pitelka on fri 24 aug 01


> I have pressure(? w/ a collar) unions in my gas lines for taking
> off my propane venturi burners for cleaning. They were hard to
> undo this last time: I hadn't cleaned my burners in a year(!).
> I'm putting them all back together, and I wonder if I can smear
> vaseline or something on the threads to make it easier to get
> them undone next time. Any opinions? I vaguely remember that I
> can't use tape on this kind of fitting....

Jennifer -
You should do two things. First, go to a good auto parts store and get a
small can of anti-sieze compound, and paint that on the mating surfaces and
the threads, and then tighten the union. Second, get larger wrenches.
Unions are commonly difficult to break loose, even when you use anti-sieze
compound, and the only solution is to use larger wrenches. For a 3/4" union
you should have a 14" pipe wrench on the small fitting and a 16" or 18" pipe
wrench on the larger fitting. Unions have flats to fit a spanner (a wrench
like a Crescent wrench) but you are best using pipe wrenches, which work
even if there are no flats. Get good pipe wrenches!
Best wishes -
- Vince

Vince Pitelka
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Home - vpitelka@dtccom.net
615/597-5376
Work - wpitelka@tntech.edu
615/597-6801 ext. 111, fax 615/597-6803
http://www.craftcenter.tntech.edu/

Jennifer F Boyer on sat 25 aug 01


Good idea. I HAVE the pipe wrenches, but only used one 16 incher
and a large vise grip. The other wrench was out on loan and next
time I'll take the time to go get it....now, anti-sieze compound
or Howard's Milk Of Magnesia: I'm going to do a test: one on
each burner . I'll let the group know how they work.....
Thanks
Jennifer

Vince wrote:
>
> Jennifer -
> You should do two things. First, go to a good auto parts store and get a
> small can of anti-sieze compound, and paint that on the mating surfaces and
> the threads, and then tighten the union. Second, get larger wrenches.
> Unions are commonly difficult to break loose, even when you use anti-sieze
> compound, and the only solution is to use larger wrenches. For a 3/4" union
> you should have a 14" pipe wrench on the small fitting and a 16" or 18" pipe
> wrench on the larger fitting. Unions have flats to fit a spanner (a wrench
> like a Crescent wrench) but you are best using pipe wrenches, which work
> even if there are no flats. Get good pipe wrenches!
> Best wishes -
> - Vince
>
> Vince Pitelka
> Appalachian Center for Crafts
> Tennessee Technological University
> 1560 Craft Center Drive, Smithville TN 37166
> Home - vpitelka@dtccom.net
> 615/597-5376
> Work - wpitelka@tntech.edu
> 615/597-6801 ext. 111, fax 615/597-6803
> http://www.craftcenter.tntech.edu/
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.

--
~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
Jennifer Boyer mailto:jboyer@adelphia.net
Thistle Hill Pottery
95 Powder Horn Glen Rd
Montpelier, VT 05602 USA
802-223-8926
http://www.thistlehillpottery.com/

Never pass on an email warning without checking out this site
for web hoaxes and junk:
http://urbanlegends.about.com/science/urbanlegends/cs/nethoaxes/index.htm
~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*