I know the water-tourch uses hydrogen and oxygen cracked from water,
but has anyone here used compressed hydrogen and oxygen as a torch
gas? Does it require a special torch and does anyone make such a
thing? What are the considerations?
Ray
Thanks Daniel!
Actually I was looking to replace my oxy/ace entirely. When you say
you “discard any remaining hydrogen” do you mean at the end of your
tankful? I’ve found a supplier with tanks roughly 5 ft tall. He has
two grades, one more pure than the other. Which do I want? Also, I
would use the H2 with oxygen, have you used it thus? I also wonder
if anyone has used H2 with N2O instead of O2?
TIA
Ray
Actually I was looking to replace my oxy/ace entirely.
I am wondering what the advantage you believe you will gain by using
hydrogen. I have used it for casting gold and sterling and my
experience I can use acetylene for casting, and acetylene or propane
for repair and fabrication. I went to hydrogen because of some
opinions I read about acetylene being a dirty gas and was responsible
for porosity problems in castings, but I was not having problems. I
just stopped using it, there was no practical reason to use it.
There were no results I could not get using propane or acetylene. If
you have not had experience using hydrogen, it might be quite
different in reality than what you imagine it to be. It is in no way
similar to a hydrogen water torch. I have a regulator I do not use in
perfect shape I would be glad to sell it. Contact me offline if you
are interested.
Richard Hart
Actually I was looking to replace my oxy/ace entirely. When you say you "discard any remaining hydrogen" do you mean at the end of your tankful? I've found a supplier with tanks roughly 5 ft tall. He has two grades, one more pure than the other. Which do I want? Also, I would use the H2 with oxygen, have you used it thus? I also wonder if anyone has used H2 with N2O instead of O2?
I would seriously consider not doing this. Hydrogen has some serious
safety issues. Certainly the biggest one is its very small size
makes keeping it where you want it a problem. It will literally leak
out through the steel cylinder it comes in, the leak rate from the
cylinder wall is to low to be a problem but any fitting, hose, valve
also is prone to leakage and these can be dangerous. You cant smell
hydrogen so your first indication of a leak could be the detonation
when you throw the light switch on entering the studio. Hydrogen
also has an extremely rapid burn rate compared to other fuel gases so
the likelyhood of a flame burning back down the torch tip and into
the hoses causing a flash back is much greater than with other fuel
gasses So you really need to be very careful on your gas pressures to
the tip making sure that they are set correctly fro the tip being
used and of corse have flashback arrestors on your torches and
regulators. You also need a H2 alarm, it is going to test the air
for hydrogen and let you know before you have an accident that you
have a leak. Also hydrogen is cooler burning than most other fuel
gasses belive it or not (see footnote below), acetylene is the
hottest at 5678 F, propane is 5111 F, and hydrogen is 5030 F so don’t
switch for more heat.
A second issue that may or may not be a concern depending on your
work, certain metals trap oxygen in the metal as oxides and when
heated in a hydrogen atmosphere the oxide reduces to pure metal and
the oxygen molecule combines with the hydrogen to make water vapor
when the oxides are inside the metals crystal matrix the water vapor
created steam blisters that ruin the metals surface. Silver, copper
and palladium are all susceptible to this problem. Palladium
especially but copper alloys also will absorb hydrogen when molten
and release it as it cools leading to gas porosity.
Propane, MAPP, Natural gas are all cleaner than acetylene and good
alternatives.
Footnote:
There is some data that shows that the flame from a water torch has
a flame temperature in excess of 6000 F
http://www.keelynet.com/energy/ oxyhyd2.htm. This number is claimed
by water torch manufacturers. The test to measure this was conducted
in an argon filled chamber and the flame was directed at some carbon
fiber which melted.The claim is that this indicates a temperature in
excess of the carbon melting point of 6422 F the claim is that this
temperature is greater due to the atomic (H) rather than molecular
hydrogen (H2) present in the gas from electrolysis of water. This is
very possibly true but we don’t solder in an argon filled chamber and
if you are talking about a hydrogen in a tank then you are using H2
not H so the common data for hydrogen flame in air with added oxygen
in a stoichiometric ratio is 5030F.
Jim
James Binnion
@James_Binnion
James Binnion Metal Arts
360-756-6550
Ray,
I meant that while hydrogen is safe to have around because it is
light, but, in a fire I personally feel that a hydrogen tank would
make quite a bomb. I am not soldering on a day to day, but rather in
batches, so I discard excess hydrogen after I am done with a batch.
Perhaps I am overly worried, I don’t know. I hope to one day find a
large enough oxy/hydro generator for regular use, but, so far the
two I tested were too small.
Some one on another reply mentioned Daniel Ballard at PM West, I
forgot about him, and would definitely recommend talking to him. Hope
this helps.
Daniel Culver
I’ve been in contact with a company that sells a unit alleged to be
large enough. The contact & info is below.
Ray
Dear Jim:
Thank you for your comments regarding hydrogen. It is my thought
they could be somewhat misleading.
“Hydrogen has some serious safety issues.”
It would have been more accurate to say bottled hydrogen. Generated
hydrogen is extremely safe, often used in munitions and chemical
facilities where fires and explosion is a critical concern. All
bottled torch gases, even inert gases can be dangerous, if not
properly handled. Bottled hydrogen being a lighter weight gas, a
smaller molecule is far safer than propane and many other commonly
used gases. This means it does not sink and accumulate but rises and
quickly dissipates away. So, it is much harder to ignite by
accident. A quick review of occurrences, even factoring in the
frequency of usage, for each common torch gas clearly shows the
heavier the gas the more likelihood of danger.
Although it is not uncommon for a gas such as propane to cause an
explosion from a pilot light, electrical switch or short, it is
extremely more difficult, which also means significantly less likely
from a hydrogen tank. Since your post mentions water welders I think
it is important to point out, it is absolutely impossible to generate
a room explosion from any form of water welders, or more advanced
hydrogen/oxygen generator, which produces even more gas (multiples).
It is not possible to generate an explosion in even in a very small
room. We have great deal of specific data on just this type of
scenario I would be happy to send to you separately.
“It will literally leak out through the steel cylinder it comes in,
the leak rate from the cylinder wall is to low to be a problem but
any fitting, hose, valve also is prone to leakage and these can be
dangerous. You cant smell hydrogen so your first indication of a leak
could be the detonation when you throw the light switch on entering
the studio.”
I have here a full size bottle of hydrogen about 4 years old, never
used which has the same tank pressure it had, when new. I agree
molecules have escaped. I have used most bottled gases for many
years. In practice, bottled hydrogen is no more prone to leakage in
actual usage or practice than other gases. Regulators, fittings and
hoses need the same leak testing you woulddo with other bottled
gases, but require nothing special to safely operate and maintain
them. All torch systems should have the proper flashback arrestors
for the specific gases being used. Can you give me a specific example
of a hydrogen detonation in any studio in North America caused by
operating a light switch. Where do you people come up with this
stuff? I can give you several examples of this happening with propane
(see JCK 04/02/02 Propane blast rocks Chicago’s jewelry district), so
I do not know how you could reject hydrogen, while recommending
propane for safety reasons. Gas density for air is 1.2929, Gas
density for hydrogen is 0.089 (floats/dissipates), Gas density for
Propane is 2.0096 (sinks/pools). If you had your choice between a
possible leak, any well trained safety director would select hydrogen
over propane.
“A second issue that may or may not be a concern depending on your
work, certain metals trap oxygen in the metal as oxides and when
heated in a hydrogen atmosphere the oxide reduces to pure metal and
the oxygen molecule combines with the hydrogen to make water vapor
when the oxides are inside the metals crystal matrix the water vapor
created steam blisters that ruin the metals surface. Silver, copper
and palladium are all susceptible to this problem. Palladium
especially but copper alloys also will absorb hydrogen when molten
and release it as it cools leading to gas porosity.”
In practice, this is only a possibility if the mixture, the ratio of
hydrogen to oxygen is not exactly a two to one mix, perfectly
combusted. With bottled gases this is a good possibility, since
regulator accuracy and precision metering of the bottled gases can be
an issue. The higher the pressures used the greater the error
possible. With a multicell hydrogen/oxygen generator this is not a
possibility since the gas is only converted from liquid (distilled or
deionized water) to gas. The gas is the same perfect mix of two
parts hydrogen, one part oxygen, the liquid was. There are also
booster fluids available which can alter the flame profile and
temperature.
"Also hydrogen is cooler burning than most other fuel gasses belive
it or not (see footnote below), acetylene is the hottest at 5678 F,
propane is 5111 F, and hydrogen is 5030 F so don’t switch for more
heat. Footnote: There is some data that shows that the flame from a
water torch has a flame temperature in excess of 6000 F
http://www.keelynet.com/energy/oxyhyd2.htm
This number is claimed by water torch manufacturers. The test to
measure this was conducted in an argon filled chamber and the flame
was directed at some carbon fiber which melted. The claim is that
this indicates a temperature in excess of the carbon melting point of
6422 F the claim is that this temperature is greater due to the
atomic (H) rather than molecular hydrogen (H2) present in the gas
from electrolysis of water. This is very possibly true but we don’t
solder in an argo filled chamber and if you are talking about a
hydrogen in a tank then you are using H2 not H so the common data for
hydrogen flame in air with added oxygen in a stoichiometric ratio is
5030F."
For higher heats oxygen would commonly be added to the gas. Years
ago it was difficult to measure high temperature, small flame, mixed
hydrogen/oxygen gas temperatures. And a number of distributors for
older water welder units like L & R, and smaller water welder
manufacturers simply “best guessed” their flame temperatures. And
there were also a lot of unusual, let us say less than scientific
methods used to “suppose and determine” temperatures. One third of
our
firm (Spirig, Switzerland) is in the temperature measurement
business, with a good portion of this work directly related to the
hydrogen/oxygen flames we generate. We have many years of experience
in this specific area. And due to a number of patented systems within
our Spirflame[tm], our flamesare within, have to be within, plus or
minus one degree of temperature. Many of our industrial customers
require this accuracy and only two or three degrees of temperature
variance would halt their production. So, the actual flame
temperatures of our Spirflame[tm] hydrogen/oxygen generator “in the
field” which has an actual mix of two parts hydrogen, one part oxygen
are:
Spirflame[tm] Gas = 3,300 degrees C or 5,972 degrees F
Spirflame[tm] Gas + Methanol = 2,700 degrees C or 4,892 degrees F
Spirflame[tm] Gas + Isopropanol = 2,500 degrees C or 4,532 degrees F
Spirflame[tm] Gas + MEK (Methyl Ethyl Ketone) = 1,700 degrees C or
3,092 degrees F
Spirflame[tm] Gas + Acetone = 1,500 degrees C or 1,500 degrees F
If we can be of any additional help or provide additional
in this area, please feel free to contact me directly.
Best Regards,
Gary
Gary W. Miller
Sr. Technical Advisor
Spirig Advanced Technologies, Inc.
35 Bronson Road Stratford, CT 06614-3654 U. S. A.
Telephone: 800 499 9933/203 378 5216 Fax: 203 386 1346
E-mail: serve4gwm@aol.com Web site: www.spirig.com
Dear Dan:
Thank you for your posting.
I hope to one day find a large enough oxy/hydro generator for regular use, but, so far the two I tested were too small.
The two units you tested were single cell units. Single cell units
are VERY limited in gas production, do not produce large flames, and
have a number of problems which come with this type of design. They
will work fine if you are only going to be doing very small items,
for only a few hours a day. Our advanced multicell technology allow
us to make much greater volumes of dry gas on demand, only as needed.
The majority of our customers for many years have been industrial
applications, usually highly automated. Although for many years we
have had a good number of very happy goldsmith, and jewelers. If you
do a search for Spirflame[tm] or my name you will find us in the
Orchid archives. For the jewelry industry we provide the
Spirflame[tm] Karat 250. Our unit is simply perfect for all phases of
torch work at the bench, and in many shops covers the needs of two
benches. I would not use it for melting, allying more than one ounce.
We have other units (more expensive) for this. Actually I prefer the
small electromelters or an induction unit for melting, casting. If
you would like our please send me your mailing address
(no PO Boxes please, we send via UPS) off line and I would be happy
to send you a complete packet. If you would like to call me, I will
be out of the office December 14th installing two more Spirflame[tm]
Karat 250’s in NYC for different customers, but I will be in the rest
of the week and next week.
Best Regards,
Gary
Gary W. Miller
Sr. Technical Advisor
35 Bronson Road Stratford, CT 06614-3654 U. S. A.
Telephone: 800 499 9933/203 378 5216 Fax: 203 386 1346
E-mail: serve4gwm@aol.com Web site: www.spirig.com