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Storage of Combustible Gases / Dangers and Risks


#1

Dear Sir at Ganoksin,
Dear Mr. Fischbein

I came across your recent Ganoksin response ... the density of
acetylene is 0.6181 whilst that of DRY air is 1.0 Thus acetylene is
lighter than air". 

John, sorry mate, …but for the first time in the many years that
I have been reading your posts, I have to disagree with you …

I have searched through the Ganoksin archive. There are numerous
articles on the risks using bottled gases.

The risk and danger problem circle around the key point:

… does my gas source have:

(a) the potential almost unlimited outflowing gas supply in case of a
leak (like a connection to a natural gas supply net) able to fill a
room quickly to a concentration above the ignition point of the gas
to air mixture, or

(b) a source of limited supply, usually a bottle of gas (propane,
acetylene, …) and again the question, is the gas volume available
from that source able to load the room or areas of it above the
ignition point of the gas to air mixture or

© the gas supply is a just-in-time gas supply, actually a gas
generator producing right on users location the needed combustible
gas to work with.

Ignition point of the gas to air mixture (volume ratio):

Acetylene: 	lower 1,5% 	/ upper 80%
Butane: 		lower 1,5 % 	/ upper 8,5 %
Propane:  		lower 1,9 %  	/ upper 9,5 %
Hydrogen: 		lower 4 % 		/ upper 77 %

These figures show that a relatively small amount of Propane or
Butane in air already creates a combustible mixture. Due to the fact
that Propane and Butane are heavier than air, there always will be
during a leak a “sea of gas” at the lowest point and there is a
diffusion zone from the “sea surface” to air running in concentration
from 100% to 0% gas in air. That means there is a mixture layer not
only running through the range of combustability, it also passes the
region where the ignition energy needed is minimale. I does not need
the “power” of an electric arc (in a switch) to ignite the mixture, a
simple static discharge is enough as an ignition source. The local
ignition (flame) then travels though the ignitable concentration
layer and this thermal shock and turbulance then starts to mix the
heavier gas with air and the released combustion energy increases
exponentially. Studying the dynamic behaviour of such detonation
development is most interesting, wouldn’t there not always and
regularly be casualties involved.

There is only one rule: Gas bottles have no right to be in a closed
room be it private or industry. Not following this basic law will
sooner or later present the bill.

Judging from a safety point of view only solutions in the © group
should be considered to be used.

Here I have to split my interests into two segments: (y) One is
safety of people using gas flames, like jewellers, but also dental
laboratories, hobbyists, and so on, and (z) The other is that my
company produces so called Multicell Electrolysers, a patented
technology used to deliver Hydrogen Gas from water and connecting to
the ordinary household ac outlet. The majority of our generators,
maybe even above 95% are used in industrial automation processes,
like automated hi-speed soldering in power / automotive electronics
assembly (GM / Delphi, Ford / Visteon, Daimler-Chrysler, and … and
… in USA and elsewhere ), even in Semicon Back-end Assembly they are
in the hundreds of systems, mostly in Asia by (Intel, Motorola, TI,
…) and by-gosh Semicon industry is the best trained industry segment
handling dangereous gases. Slogan there is " if you can avoid it,
then do it!

WHAT surprises me in the Ganoksin discussions, nobody talks on the
safe solution using JIT gas production.

Maybe the electrolyzing technology is not much known in the
jewellers community or the reputation of electrolysers has been badly
damaged by the first single-cell systems electrolyzer introduced many
years ago (25?) to the US by imports and local manufacture.

Single-cells have by basic physical reasons no chance for a
continued reliable operation.

Our patented Multicells have opened the industrial market almost 10
years ago and there are leading automation houses in the US and
abroad integrating our systems in assembly lines. If your cars ABS
break system works reliably, or the air bag ignites properly, there
is a high chance our microflame system Spirflame=AE is involved to
produce 100% yield solder connections.

Ganoksin, that was a long story for a short idea:

Ganoksin seems to me the organisation with the knowledge and
integrity to ignite a discussion in the jewellers community along
the theme “Why is the safe JIT technology not Used or Known or
Accepted”?

My wish is to ignite a storm of discussions and maybe help to
improve the safety awareness in the jewellers community. As
discussion ignites, we will have a lot of to thread into
this JIT theme.

With best regards and my best wishes for a peaceful X-mas / New Year
2003 to All Ganoksin members.

Ernest Spirig http://www.spirig.com/greetings/xmas.html

Spirig Ernest
http://www.spirig.com


#2
"Why is the safe JIT technology not Used or Known or Accepted"? 

the “water” torches, such as the Spirig machines, ARE known and
accepted, by those for whom they are good solutions. But they are
characterized, among other things, by relatively small flame sizes.
This makes them well suited to precise assembly and soldering of
small items, especially in metals like gold and platinum. For those
workers doing larger items in silver, which is highly heat
conductive, the oxy/hydrogen flames can be somewhat harder to use
and control than the much larger soft flames of an air/acetyelene
unit. It just depends on what youi’re doing. I own and use both
types of torch, though sadly, my water torch isn’t a spirig, but an
L&R (which still works just fine, thanks). for many tasks, it’s
perfect. but for many others, I simply prefer the traditional
torch. While I’m sure there are larger versions available, I’ve never
seen a “water” torch, of any brand, that could do a good job of
things like melting metal for ingots or casting, or annealing larger
pieces of silver jewelery.

And there’s one other little detail…

Cost. For the cost of the average "water’ torch, I can set up
several oxy/gas torches… While the water torches are very nice for
precise exacting jewelery work, there are a lot of craftpeople who
simply do not have the budget to afford one. Even the older used
model I bought on ebay wasn’t cheap…

Peter Rowe


#3
WHAT surprises me in the Ganoksin discussions, nobody talks on the
safe solution using JIT gas production "Why is the safe JIT
technology not Used or Known or Accepted"? " 

Ernest There have been discussions on Orchid on the water torch,
which I believe would fit your definition of “just in time” JIT
electrolyser technology.

Could you please provide some idea of the cost of one of the Multi
cell Electrolyser systems sold by your company which is size
compatible with a one man studio operating a single torch.

Regards
Milt Fischbein
Calgary Canada