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Conundrum

Thu Aug 09 2018, 09:54AM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4062

Hi, I recently had an intriguing discussion regarding the mire of legal regulations surrounding gases, both inert and otherwise.

As far as I can make out, shops are allowed to sell cylinders fine as this is a "low risk".

If you have an existing oxy-acetylene system which is at least approved, provided it is maintained correctly by an engineer who has the "Gas Safe" certification then this can be used as long as it is 1) outdoors, and 2) clearly cordoned off and secured so silly fools can't mess with it.
One biggie is to ensure that only safe carriers are used. Anything that can tip over or fall is unsafe.

Oxygen *systems* are permitted if for medical use: see appropriate regulations and in fact the cylinders for such use are higher grade and often far more suitable (and expensive!) due to low CO2/etc contamination.
Any other use depends on the exact configuration.
The difficulty I have is getting parts: buying a used oxy setup is possible but the second I buy it the chances are it will become illegal and need to be re-certified due to the Gas Safe issue.
If the acetylene part is empty (likely) then this is even more complex as it would be an off-label use and I'd be at risk of legal repercussions even if following best practice.
One thing I must *never* do is leave it in a vehicle, etc unattended as this would be considered "failure to adequately secure" and as such a certified padlock would then be needed on both regulators to ensure this can't be turned on by accident.

The regulators sold specifically for oxygen are "idiot proof" and thus far more expensive.
One thing they do insist upon is using correct lubrication and never to use anything else as this *WILL* void warranty and other
such legal protections in addition to being a severe fire risk.
Buying from overseas may be feasible but its a risk given the above.

Sorry to rant but have I missed anything?

Sulaiman

Thu Aug 09 2018, 10:00AM

Registered Member #162 Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140

About one year ago I telephoned my local B.O.C. depot;
. for private use they can deliver oxygen, acetylene, regulators etc.
. no license required for ownership, storage or usage
. may invalidate insurance and mortgage policies

Ash Small

Thu Aug 09 2018, 06:02PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

Due to the unique hazards associated with acetylene cylinders, surely it makes more sense to use oxy-propane these days, as it is at least as readily available as acetylene, and at least as efficient?

Sulaiman

Fri Aug 10 2018, 08:01AM

Registered Member #162 Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140

oxy-propane seems to be favourite for scientific glass blowers / lampworkers,

the risks associated with acetylene cylinders are quite low,
by my amateur science and engineering standards - very low.

if you are going to have a home gas torch then why not go for the highest temperature practicable

moderately priced used oxy-acetylene torches are available via eBay.

Conundrum

Sat Aug 11 2018, 05:45PM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4062

As its the oxygen I need (for HTSCs) this may simplify things.

Hazmatt_(The Underdog)

Sat Aug 11 2018, 06:08PM

Registered Member #135 Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735

Oxy Propane is ~ 4800 F, There's no need for Acetylene.

I'm not a good glassblower, but propane works fine.

I was given a bottle of Propylene, but it is a miserable gas to burn, it is very sooty and clogs the torch, so it forces you to shut down every so often. I never had that problem with Propane.

The other issue is you are wearing Dydimum glasses to block out the soda flare, but guess what, Acetylene burns with such intensity (breaking triple bonds) that you get a LOT of UV coming off that cone, so you're staring at UV for hours on end with the wrong protection on your eyes... NOT A GOOD IDEA!

And you wouldn't be able to 'read' the glass with a shade 3 And Didymium glasses on at the same time.

So just use Propane.

With a multi-fuel tip you can cut steel (we cut up to 1/2" thick with a cheapo torch handle)

And mostly what I use are the National Blowpipes. They are reasonably priced, and you can change the tips easily.
I like the #3 tip for most jobs, that's small tubing.

For any real work you do need a foot switch for an oxygen boost, which is better to be an electric solenoid over a mechanical hydraulic switch. I have to rig up an electronic solenoid some day, I use the mechanical switch for a long while but it can be awkward.

radiotech

Mon Aug 13 2018, 05:13AM

Registered Member #2463 Joined: Wed Nov 11 2009, 03:49AM
Location:
Posts: 1546

In the first place, I am not a welder. But have worked with them in many
aspects of industrial electricity. Often in dingy dark places when something broke down.

A welder can quickly adjust his torch to produce a brilliant light so others can see.

He holds it aloft.

Can oxy-propane do this as well ?

The welder doesn't need light to weld. All his comes through his mask glass.

Ash Small

Mon Aug 13 2018, 09:14AM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

radiotech wrote ...

In the first place, I am not a welder. But have worked with them in many
aspects of industrial electricity. Often in dingy dark places when something broke down.

A welder can quickly adjust his torch to produce a brilliant light so others can see.

He holds it aloft.

Can oxy-propane do this as well ?

The welder doesn't need light to weld. All his comes through his mask glass.

Oxy-propane is just as bright as oxy-acetylene.

A foot switch was mentioned above, but the torches I've used had a trigger to control oxygen feed.

the_anomaly

Mon Aug 13 2018, 11:51AM

Registered Member #19 Joined: Thu Feb 02 2006, 03:19PM
Location: Jacksonville, FL
Posts: 168

Oxy Propane is ~ 4800 F, There's no need for Acetylene.

For glass blowing I'm sure its fine but for steel work you want acetylene. That extra flame temp makes a difference when trying to locally heat a spot.

As its the oxygen I need (for HTSCs) this may simplify things.

What is HTSCs?

Ash Small

Mon Aug 13 2018, 01:47PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

the_anomaly wrote ...

Oxy Propane is ~ 4800 F, There's no need for Acetylene.

For glass blowing I'm sure its fine but for steel work you want acetylene. That extra flame temp makes a difference when trying to locally heat a spot.

This is rubbish, oxy-propane will cut through inch thick steel instantly if you want it to.

Do you actually have experience of using an oxy-propane torch?

I don't think I've even seen an oxy-acetylene set in forty years, I used to regularly use oxy-propane for cutting in places I worked during the noughties.

EDIT:- "A common propane/air flame burns at about 2,250 K (1,980 Â°C; 3,590 Â°F),[2] a propane/oxygen flame burns at about 2,526 K (2,253 Â°C; 4,087 Â°F),[3] an oxyhydrogen flame burns at 3,073 K (2,800 Â°C; 5,072 Â°F), and an acetylene/oxygen flame burns at about 3,773 K (3,500 Â°C; 6,332 Â°F).[4]"

oxy-acetylene is hotter than oxy-propane, but when are you going to need more than 2,250C?

Propane is cheaper than acetylene, and easier to transport/store. Propane uses more oxygen, but is cheaper and easier to live with.

EDIT:-

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