I recently changed the oxygen bottle on my gas welding setup, and felt
a significant leak onto the back of my hand from the coupling between
the regulator and the oxygen bottle. This turned out to be a fault
with the oxygen bottle itself, which was replaced by the supplier.
Being a bit hard of hearing, I would not have heard any hiss (even if
there was one), and it was lucky I wasn't wearing my welding gloves at
the time otherwise I would have been none the wiser about the leak.
The question arose in my mind about routine checking for leaks (or at
least when changing bottles in the future). My supplier suggested that
water could be used, but cautioned against adding washing-up liquid;
he did not know of any commercial leak-detecting liquid.
Any suggestions?
CRB

The question arose in my mind about routine checking for leaks (or at
least when changing bottles in the future). My supplier suggested that
water could be used, but cautioned against adding washing-up liquid;
he did not know of any commercial leak-detecting liquid.
Any suggestions?
CRB

Something like this might be of use;

http://www.toolstation.com/index.htm...4rA81HTMS3Kimm

Patrick

crb wrote:
I recently changed the oxygen bottle on my gas welding setup, and felt
a significant leak onto the back of my hand from the coupling between
the regulator and the oxygen bottle. This turned out to be a fault
with the oxygen bottle itself, which was replaced by the supplier.
Being a bit hard of hearing, I would not have heard any hiss (even if
there was one), and it was lucky I wasn't wearing my welding gloves at
the time otherwise I would have been none the wiser about the leak.
The question arose in my mind about routine checking for leaks (or at
least when changing bottles in the future). My supplier suggested that
water could be used, but cautioned against adding washing-up liquid;
he did not know of any commercial leak-detecting liquid.


What was his reason behind "don't add washing up liquid"?

When I worked in a lab, each lab had its own bank of cylinders (oxygen,
nitrogen, sometimes argon, and sometimes acetylene). Next to each bank
was a dedicated washbottle used for testing connections whenever a new
cylinder was fitted. This contained water with a squirt of washing up
liquid. Always worked.


--
Grunff

On 22 Dec 2005 02:12:29 -0800, "crb" wrote:

My supplier suggested that
water could be used, but cautioned against adding washing-up liquid;
he did not know of any commercial leak-detecting liquid.

Use weak detergent solution in water - but the detergent should be
something like Teepol (BOC's own recommendation) that's _just_ a
detergent, not the typical "washing up liquid" that's thickened with
salt. I use Ecover (from the kitchen), same as I use to wash the car
(and for much the same salt-free reasons).

If you're stuck, drool on it (ask Dr Drivel for expert instructions).
Don't spit on it, you can't tell if they're your bubbles or the
cylinders'.

Be very careful in looking for leaks around the high pressure oxygen
side. Also keep the cylinder valve covers in place and check for dirt
before connecting. There's a ridiculous pressure in those cylinders and
it's enough to cause accidents you wouldn't imagine where possible.

"Andy Dingley" wrote in message
news
On 22 Dec 2005 02:12:29 -0800, "crb" wrote:

My supplier suggested that
water could be used, but cautioned against adding washing-up liquid;
he did not know of any commercial leak-detecting liquid.

Use weak detergent solution in water - but the detergent should be
something like Teepol (BOC's own recommendation) that's _just_ a
detergent, not the typical "washing up liquid" that's thickened with
salt. I use Ecover (from the kitchen), same as I use to wash the car
(and for much the same salt-free reasons).

If you're stuck, drool on it (ask Dr Drivel for expert instructions).
Don't spit on it, you can't tell if they're your bubbles or the
cylinders'.

Be very careful in looking for leaks around the high pressure oxygen
side. Also keep the cylinder valve covers in place and check for dirt
before connecting. There's a ridiculous pressure in those cylinders and
it's enough to cause accidents you wouldn't imagine where possible.

and don't let anything oil based near it & don't use ptfe tape

Regards Jeff

Jeff wrote:
"Andy Dingley" wrote in message
news
On 22 Dec 2005 02:12:29 -0800, "crb" wrote:


My supplier suggested that
water could be used, but cautioned against adding washing-up liquid;
he did not know of any commercial leak-detecting liquid.

Use weak detergent solution in water - but the detergent should be
something like Teepol (BOC's own recommendation) that's _just_ a
detergent, not the typical "washing up liquid" that's thickened with
salt. I use Ecover (from the kitchen), same as I use to wash the car
(and for much the same salt-free reasons).

If you're stuck, drool on it (ask Dr Drivel for expert instructions).
Don't spit on it, you can't tell if they're your bubbles or the
cylinders'.

Be very careful in looking for leaks around the high pressure oxygen
side. Also keep the cylinder valve covers in place and check for dirt
before connecting. There's a ridiculous pressure in those cylinders and
it's enough to cause accidents you wouldn't imagine where possible.


and don't let anything oil based near it & don't use ptfe tape

Regards Jeff


You can use PTFE tape the oil free kind, and snoop is the commerical
name for a leak detecting fluid.

Paul

"crb" wrote in message
oups.com...
I recently changed the oxygen bottle on my gas welding setup, and felt
a significant leak onto the back of my hand from the coupling between
the regulator and the oxygen bottle. This turned out to be a fault
with the oxygen bottle itself, which was replaced by the supplier.
Being a bit hard of hearing, I would not have heard any hiss (even if
there was one), and it was lucky I wasn't wearing my welding gloves at
the time otherwise I would have been none the wiser about the leak.
The question arose in my mind about routine checking for leaks (or at
least when changing bottles in the future). My supplier suggested that
water could be used, but cautioned against adding washing-up liquid;
he did not know of any commercial leak-detecting liquid.
Any suggestions?

Do those oxygen bottles not have to be pressure tested / crack tested in the
same way that scuba tanks have to be tested ? And marked accordingly

crb wrote:
I recently changed the oxygen bottle on my gas welding setup, and felt
a significant leak onto the back of my hand from the coupling between
the regulator and the oxygen bottle. This turned out to be a fault
with the oxygen bottle itself, which was replaced by the supplier.
Being a bit hard of hearing, I would not have heard any hiss (even if
there was one), and it was lucky I wasn't wearing my welding gloves at
the time otherwise I would have been none the wiser about the leak.
The question arose in my mind about routine checking for leaks (or at
least when changing bottles in the future). My supplier suggested
that water could be used, but cautioned against adding washing-up
liquid; he did not know of any commercial leak-detecting liquid.
Any suggestions?

Your regulator will have a cylinder contents gauge; ensuring it's output is
turned off, fit the regulator to the new cylinder, turn on the cylinder
valve and observe the gauge indicates a full cylinder, turn off the cylinder
valve and watch the gauge - if it starts to fall you have a leak. Of course
this may be either the regulator or the cylinder connection - to narrow it
down you'll need some leak detector fluid. This should really be just a
plain detergent (BOC recommend 'Teepol'). As with all high pressure
cylinders it is very important to avoid anything oily or oil based coming
into contact with the valves; this includes hand creams and barrier creams!

Dave

Gizmo wrote:
"crb" wrote in message
oups.com...
I recently changed the oxygen bottle on my gas welding setup, and
felt a significant leak onto the back of my hand from the coupling
between the regulator and the oxygen bottle. This turned out to be
a fault with the oxygen bottle itself, which was replaced by the
supplier. Being a bit hard of hearing, I would not have heard any
hiss (even if there was one), and it was lucky I wasn't wearing my
welding gloves at the time otherwise I would have been none the
wiser about the leak. The question arose in my mind about routine
checking for leaks (or at least when changing bottles in the
future). My supplier suggested that water could be used, but
cautioned against adding washing-up liquid; he did not know of any
commercial leak-detecting liquid.
Any suggestions?

Do those oxygen bottles not have to be pressure tested / crack tested
in the same way that scuba tanks have to be tested ? And marked
accordingly

Yes, they are tested - the test pressure should, along with other
information such as date of manufacture and water capacity, be stamped into
the neck of the cylinder. There is usually a plastic ring around where the
valve meets the cylinder body indicating when the next test is due.

Dave

"crb" wrote in message
oups.com...
I recently changed the oxygen bottle on my gas welding setup, and felt
a significant leak onto the back of my hand from the coupling between
the regulator and the oxygen bottle. This turned out to be a fault
with the oxygen bottle itself, which was replaced by the supplier.
Being a bit hard of hearing, I would not have heard any hiss (even if
there was one), and it was lucky I wasn't wearing my welding gloves at
the time otherwise I would have been none the wiser about the leak.
The question arose in my mind about routine checking for leaks (or at
least when changing bottles in the future). My supplier suggested that
water could be used, but cautioned against adding washing-up liquid;
he did not know of any commercial leak-detecting liquid.
Any suggestions?
CRB

most plumbers places sell aerosol leak detector that is safe for any gas
(Mark Vittow), or a very dilute washing up solution is the most commonly
used.

The leak you describe is often caused by the taper insert in the outlet, it
comes loose easily, you 'can' tighten it with an allen key, but getting them
to change the bottle is better.

mrcheerful

Patrick wrote:

Something like this might be of use;

http://www.toolstation.com/index.htm...4rA81HTMS3Kimm


Thanks for the suggestion. I already have a can of that, and have
successfully used it on natural gas installations, but it does not
specifically mention oxygen, so I was wary about using it. I have
asked the manufacturer/distributor for their opinion - no reply yet.
CRB

Grunff wrote:
What was his reason behind "don't add washing up liquid"?

Grunff

He didn't give a specific reason, only that "oxygen is funny stuff".
Perhaps he was just being super-cautious, as he said he might use
washing up liquid himself, but he wouldn't advise anyone else to, and
recommended just plain water.
CRB

Grunff wrote:
crb wrote:
I recently changed the oxygen bottle on my gas welding setup, and felt
a significant leak onto the back of my hand from the coupling between
the regulator and the oxygen bottle. This turned out to be a fault
with the oxygen bottle itself, which was replaced by the supplier.
Being a bit hard of hearing, I would not have heard any hiss (even if
there was one), and it was lucky I wasn't wearing my welding gloves at
the time otherwise I would have been none the wiser about the leak.
The question arose in my mind about routine checking for leaks (or at
least when changing bottles in the future). My supplier suggested that
water could be used, but cautioned against adding washing-up liquid;
he did not know of any commercial leak-detecting liquid.

What was his reason behind "don't add washing up liquid"?

Washing up liquid has enough organic content that it could concievably
burn in high pressure oxygen. (practically anything will)
Once the detergent-water falls off, a film of water/detergent will be
left, and it'll leave a thin film of 'pure' detergent, once it dries.

While this is _probably_ not a risk, especially if you use it at the bare
minimum concentration, where it only reduces the surface tension, without
any extra, putting films that could concievably burn on a surface that'll
be exposed to 3000PSI oxygen is something that is generally only done after
extreme thought.

On 22 Dec 2005 22:53:45 GMT, Ian Stirling
wrote:

Washing up liquid has enough organic content that it could concievably
burn in high pressure oxygen. (practically anything will)
Once the detergent-water falls off, a film of water/detergent will be
left, and it'll leave a thin film of 'pure' detergent, once it dries.

So what ? _Fingerprints_ will burn in high pressure oxygen. But
there's little fuel mass, so it's no big deal. Same for detergent traces
- the salt worry is about corrosion of the fittings.

PTFE tape cant be used on high pressure oxygen because of its cold flow
behaviour - it can literally be squeezed out of the joint. For tapered
threads after the first reducing orifice (such as the gauges) it's OK.
Fluorine compounds aren't really interested in burning in mere oxygen.