Co2 Cylinder Screw-down Valve: Your Worst Nightmare

[claymen]

Exactly!

Better still, $15.000 boat over 10 years will "only" cost you $4 per day....

Now, try to convince you wife in this sort of math

You don't sell it to her on the math, sell it to her with the diamonds and jewelery she gets. "Hi hun I bought you a diamond necklace, now don't worry it wasn't too expensive only $5/day over 10 years AND we get a free boat with the necklace!"

 

[claymen]

Fair point claymen. I was probably a bit blunt before, and i apologise for that. You are right in that in has been blown out pf proportion. I wouldn't use an extinguisher, but then again, i no chill, and we all know the dangers of that!!.

Cheers

No worries

I had my hesitations at first about it as well which is why I asked the place I bought it from specifically about it. And he said there wasn't any issues with it, its a fully tested tank and has all the correct fittings. And he was right, I just hooked up my reg and it worked perfectly. Just need my keg fittings and I can start carbonating some beer!

 

[KHB]

Im in the camp where i dont have a prob using one but the valve has failed on mine for the second time, it came from the same place as crundle who has had it happen 5 times! Gets me wanting to buy a kegonlegs cylinder.

 

[claymen]

Im in the camp where i dont have a prob using one but the valve has failed on mine for the second time, it came from the same place as crundle who has had it happen 5 times! Gets me wanting to buy a kegonlegs cylinder.

What's actually failing?

 

[paul]

It seems that people are too tight to pay the rent on a cylinder.

Rather than dicking around with fire extinguishers why don't people just acquire an empty co2 cylinder, in the same manner that they acquire pub kegs?

Once you have a cylinder you can either get it filled by your fire extinguisher mate or hire one from the company whos cylinder it is and return the empty. This gets you into kegging with the right gear to do the job and away from the hassles of paying rent.

 

[crundle]

In the pictures that I posted on this thread, there is one of the pin inside the handle assembly. The O ring near the top of the pin eventually lets gas past it, and this vents the cylinder, slowly, but surely. Another forum member has fixed his problem by using a slightly larger O ring, so it gives a more positive seal, as when I checked mine once it had emptied, it gave almost no resistance against the tunnel it travels in.

Crundle

 

[claymen]

I think everyone is forgetting that a fire extinguisher is still just a CO2 bottle with a different fitting for dispensing the gas.

As paul changed his post I cant quote him but there are single use extinguishers and there are those that can be refilled.

Turning it on and off shouldn't be an issue if the right fitting is used on the bottle which I think is where people are getting confused. Hacking up the standard fitting isn't a good idea, using a proper fitting should be fine.

 

[cooperplace]

I think everyone is forgetting that a fire extinguisher is still just a CO2 bottle with a different fitting for dispensing the gas.

As paul changed his post I cant quote him but there are single use extinguishers and there are those that can be refilled.

Turning it on and off shouldn't be an issue if the right fitting is used on the bottle which I think is where people are getting confused. Hacking up the standard fitting isn't a good idea, using a proper fitting should be fine.

Claymen,

you're 100% right, but getting that correct fitting is well-nigh impossible, it seems.

Peter

 

[Justin]

Lots of discussion here and lots of arguments. I have no concerns with using a fire extinguisher, it is safe if used properly like any pressurized cylinder. It may leak eventually but it is a safe CO2 bottle as it was designed, the possibility of leakage is the trade off with an extinguisher. Modifying was not in the design parameters however.

My point of concern is those people "trying" to match up the right thread wondering if tapered will work with parallel, 3/4 this 5/8 that, whatever they are trying to do. This is absolutely the wrong area to entertain your DIY brilliance. You are dealing with threads cut in aluminium, it is an incredibly soft metal and it's strength is pathetic. If you dont get the exact correct threads you run a huge risk of the thread cut in the aluminium cylinder stripping out and then you have a rocket on your hands (or out of your hands as the case will most certainly be) and one hell of a lot of not-so-contained energy. Use the correct original fitting or a original equivalent (eg. the screw down valve) designed for the cylinder or dont do it at all. If you mess up with your calculations you place a lot of people at risk. "It looks pretty close" is a recipe for disaster with potentially fatal consequences, it's just not an area where she'll be right works. I acknowledge the efforts to try to get the correct information on the thread type, it's unfortunate it seems to be a tough one to find an answer to, but if any of you even thought "it looks pretty close" then you dont know what you are dealing with and I suggest you go get a cylinder from BOC and live another day.

FWIW, just because someone works/runs the place that fills the cylinders does not necessarily elevate them to an expert and it would be foolish to assume that they actually know what they are doing or qualified to make the call on what you can get away with. Hell, there has never been a work place accident from an "experienced" person or some one who should have known better and even the best make mistakes or use poor judgement.

Now using the cylinder without modification poses no greater risk. If you can deal with the likely eventual leak then your golden. If you dont want to do that then get a kegsonlegs or BOC. Just whatever you do please dont try to get creative with a valve fix. The guy filling your cylinder is going to be a great risk and I think if you told him you switched out the fitting he'd be none to impressed to put his life on the line.

Sorry for being the party pooper and assuming the worst but you may only get one shot at this and worst still you may put someone elses life unwillingly at risk. Good luck in your search for solutions.

Justin

 

[claymen]

Lots of discussion here and lots of arguments. I have no concerns with using a fire extinguisher, it is safe if used properly like any pressurized cylinder. It may leak eventually but it is a safe CO2 bottle as it was designed, the possibility of leakage is the trade off with an extinguisher. Modifying was not in the design parameters however.

Again it shouldn't leak if done properly. I am not advising people to use the wrong thread or guestimate one. You can still get a leak on any tank just as easily as anything else if things aren't done right.

FWIW, just because someone works/runs the place that fills the cylinders does not necessarily elevate them to an expert and it would be foolish to assume that they actually know what they are doing or qualified to make the call on what you can get away with. Hell, there has never been a work place accident from an "experienced" person or some one who should have known better and even the best make mistakes or use poor judgement.

That may be the case but we aren't asking him to do any of the mods with fittings we provide. We are asking a licensed workshop to tests cylinders for a tank suitable for homebrew. If it's not safe then he is selling a defective and dangerous product and I doubt any business would want to risk the liability of doing so. It's the same reason places won't fill unknown tanks which is fair enough (although annoying if its stamped right and has the right fittings).

Now using the cylinder without modification poses no greater risk. If you can deal with the likely eventual leak then your golden. If you dont want to do that then get a kegsonlegs or BOC. Just whatever you do please dont try to get creative with a valve fix. The guy filling your cylinder is going to be a great risk and I think if you told him you switched out the fitting he'd be none to impressed to put his life on the line.

I don't see how there will be a leak if the fittings are done properly. Any tank can leak for a variety of reasons.

Sorry for being the party pooper and assuming the worst but you may only get one shot at this and worst still you may put someone elses life unwillingly at risk. Good luck in your search for solutions.

Justin

I'm all for being safe, hence why I went to a place to buy the tank for a specific use. Whilst I agree that doing a DIY and attempting to match threads is a recipe for disaster I don't believe that a fire extinguisher tank is any more likely to leak if the correct fittings are used and its done by a professional. A tank is a tank, and saying that a fire extinguisher is more likely to leak just because its a fire extinguisher is false logic. If that were true then they wouldn't pass the proper testing ever. You don't exactly want a leaking CO2 tank, especially one that for most people will be indoors in the case of an extinguisher.

 

[Justin]

Hi mate, I dont disagree with any of your points and in fact most of my comments were not even really directed your way. I acknowledge your efforts to do it properly and you are being very thorough, it was some of the other comments of what the thread "might" be and what other people were doing to try and make these work that were worrying particularly those instances where regulators have blown off. F$&k me, if the threads aren't right do you think a bit of teflon will hold 800psi on a thread that you can basically rattle the fitting loose on? These are the worrying actions. However in your specific aim I wish you luck and hope you can find a solution, you certainly are going about it the right way. It's just the other stories that scare the life out of me and it worries me what people will do and what they think is safe.

Regarding the leaking fire extinguishers, i agree there is nothing about the fact of it being a fire extinguisher that means it will leak. If you have the right fittings and set up it wont leak, it's just a tank. I'm refering to the use of the original squeeze grip valves which seem less than ideal for our use, obviously they aren't designed to be repeatedly opened and closed and thus they end up leaking past the oring. If you can get a better valve (screw down/gate valve) it will work much better for longer. I have a Chubb 5kg cylinder that has a slow leak past the oring, next time I fill it I will replace the oring and I will make particular note to not use the valve to open and close the cylinder but will instead just use the regulator. Someone else mentioned they still leak if used like this, to be honest I dont know if it will solve it or not but I initially didn't use the valve for exactly that reason and just used my regulator to turn it off and it was working fine for a very long time. I eventually got a bit lazy and started using the valve to give bursts for whatever I was doing at the time and it eventually started leaking. I've had my extinguisher for probably 6(?) years now and been using it for a very long time. If you search back you can even find my original posts on the chubb extinguishers fitting CO2 regulators directly.

Good luck with it. Justin

FWIW I know just how dangerous pressure can be. I've had a 4500psi 44cuft scuba tank shift in the car and crack the valve open, it didn't open fully but it dumped probably 3500psi in a few seconds before I could shut it, it fogged all the windows in the car, froze the bottle and was unbelieveably loud. Luckily I was still in the car park and not on the freeway and luckily I had secured the bottle or it may have taken off, it had just shifted slightly and knocked open the valve when something else moved past it. In the same week the airgun shop I go to was filling a 4500psi bottle when the line blew, it sat spinning at god knows what speed on top of the work bench before it flew out the door across the car park and slammed into a parked car. Yes this is 4500psi, but even 800psi with 5kg of CO2 is a massive amount of energy and if your reg blew off you now have unregulated gas venting that could cause a flying cylinder. Just passing on a few personal experiences.

 

[claymen]

Fair enough, apologies if you took offense in any way.

You are 100% correct, the DIY way that some are attempting is not cool with the wrong fittings. It has to be the correct fittings or nothing. Coming from a background building up my car there is no way in hell I would use the wrong fitting for any fluid connections, and CO2 tanks are no different (albeit gas connections). Maybe people see CO2 as "harmless" or something, but you wouldn't use an incorrect fitting on say your fuel line/fuel rail would you? So why do the dodge on a CO2 tank that's probably even more dangerous.

In any case, I would suggest people get a professional to install the correct fittings and test things properly. Not that expensive to get done. And if you can't spend the time to chase that up just buy a mykegsonlegs or similar. Do a little research and do things properly and we can all enjoy a nice cold beer at the end of the day

 

[KHB]

What's actually failing?

The little button that depresses when you push the handle down.

 

[MHB]

What I was trying to get across is that "Work Cover" is taking an interest. They will be looking at bottle refillers and I hear sending in mystery shoppers to see if refillers are complying with the rules and handing out fines if they aren't.
Be aware that if this starts happening it might start getting a lot harder to have questionable bottles filled.

If you are thinking of buying or modifying an extinguisher take this into account.

Hay I'm not saying that the law is always sensible, but I once got a ticket and a defect notice slapped on my old jeep, for fitting "Lap Sash" seatbelts, the car came with only a lap belt, I had to go and get an engineer's certificate to change the car to make it safer. Crikey this thing had no doors, sharp cornering got real scary real quick.
OK I was young and stupid and I wound the copper up lesson learned.

MHB

 

[claymen]

I still think there is something missing here...

Even that certification doesn't sit right. Upon further reading it is simply stating that the product being sold as a fire extinguisher complies with AS 1841.6:1997. This seems to be more to define it as a suitable fire extinguisher, not that the bottle is certified. If you check out the firebox website they list all their certificates and they cover everything from tanks to hose reels and that they are suitable for use as fire suppression devices. I can dig further but my guess is this would tie into the legality surrounding businesses and the requirements to have adequate fire safety and probably work cover ties in there also.

Also, further to your original post regarding the work cover aspects on page one.

Further reading of point 1 indicates that no pressure vessel may be used for any purpose other than that for which the certificate was issued.
My reading of this clause leads me to believe that modifying a fire extinguisher for any other use is illegal.

This looks possibly incorrect as per "The Occupational Health and Safety Regulation 2001" Section 136A Use of plantparticular risk control measures sub section 1b it would imply otherwise.

136A   Use of plantparticular risk control measures

		(1)  An employer must ensure in relation to use of plant that:

			(a)  plant (with the exception of lifts that are operated by members of the public and coin-operated amusement devices) is not operated by a person unless the person has received adequate information and training and is supervised to the extent necessary to minimize the risks to health and safety, and

			(b)  plant is used only for the purpose for which it was designed unless a competent person has made an assessment that the change in use does not present an increased risk to health or safety, and

In our case a plant is defined as a gas cylinder as per section 107 table Part 1 General Plant

Part 1   General plant

Boilers and pressure vessels categorized as being of hazard level A, B, C or D according to the criteria in AS 43431999

Gas cylinders

After reading that, it would appear that it is legal and completely within the guidelines so long as a competant person has checked it out. However, this does not cover a home DIY job. I can only see this being valid in the case of say a cylinder testing shop or someone else accredited checking it.

Short of the tank being in breach of AS 2030 Workcover would have no grounds in issuing a fine for filling these types of bottles. Now the only outstanding part is reading up on AS 2030 which I hopefully should have a copy of soon.

References:

• Occupational Health and Safety Regulation 2001

 

[Leigh]

Claymen,

Your interpretation may well be valid, and many may operate in this manner under the assumption that the courts will agree, but until the courts make a ruling, it is only an interpretation, and not the current legal status...

Legal advice we get at work always revolves around precedents set in other cases or the level of comfort the lawyers have that we will be able to convince the courts to agree with us.

The law works in mysterious ways...

Cheers

 

[claymen]

Seems pretty clear to me, the only issue is the definition of "competent"

It does concern me a little that it says competent and not "licensed" as that would have been even clearer that DIY @ home is not ok. However as it stands it could be argued either way. With that said, I don't see there being any issue with a licensed/accredited person or workshop making the assessment that it is ok, else why bother having people accredited at all.

The law does work in mysterious ways, but its bent and twisted by lawyers who want to get the best result for "their" client regardless of what side they may be on. So the question comes down to, who would benefit the most by swinging it one way or the other?

 

[crundle]

Just to clarify things as to what I am hoping to achieve, I was researching on ways to overcome the inherent problem with using a CO2 extinguisher as a kegging cylinder, namely that the O ring in the valve pin eventually fails as it was not designed to hold pressure for long periods or (many) repeated uses. I was open to many ways of overcoming this, from using screw down valves rated for CO2 at typical cylinder pressures, through to using a slightly larger O ring to give a tighter seal and retain pressure longer.

In all these ideas, I have been communicating with the licensed filler who has worked with fire extinguishers for many many years. He is no fool, and would not agree to anything that would be dangerous or suspect in his opinion. He sees that using a screw down valve may be quite suitable, and this has been done by other licensed fire extinguisher refitters/refillers with success. However, the valves are hard to come by these days, and there are many different threads to deal with also, so this may not be the best way to pursue the matter.

On the other hand, if the original O ring could be *safely* replaced with one that is slightly larger, and therefore able to give a better seal for a longer amount of time, then what is the harm? Fire extinguishers used for kegging seem to eventually leak through the O ring, so if the larger one leaks eventually you are still in the same position you were before, but if it can seal long enough to allow the gas to be used before it fails, then it can simply be replaced at each filling. A larger O ring is not likely to cause any other issue that I can see, as long as it is able to travel up and down the tunnel without deforming in the process.

As always, I will discuss the use of the larger O ring with the licensed refiller first.

Crundle

 

[crundle]

The law does work in mysterious ways, but its bent and twisted by lawyers who want to get the best result for "their" client regardless of what side they may be on. So the question comes down to, who would benefit the most by swinging it one way or the other?

Being a lawyer, I agree with you that the law is bent by lawyers for the benefit of their clients. We like the law to be grey as that gives room to maneuver. As homebrewers, it is in OUR best interests to find safe ways to use fire extinguishers for kegging, and having an open discussion on how to improve the mechanics of the fire extinguishers is part of that process. I appreciate the comments of those who don't advocate using fire extinguishers as they provide balance, but perhaps combined, we will be able to find a solution that is safe and effective.

Crundle

 

[claymen]

Being a lawyer, I agree with you that the law is bent by lawyers for the benefit of their clients. We like the law to be grey as that gives room to maneuver. As homebrewers, it is in OUR best interests to find safe ways to use fire extinguishers for kegging, and having an open discussion on how to improve the mechanics of the fire extinguishers is part of that process. I appreciate the comments of those who don't advocate using fire extinguishers as they provide balance, but perhaps combined, we will be able to find a solution that is safe and effective.

Crundle

Is your guy just a filler or a cylinder tester as well? Just wondering because if he isn't a tester maybe it would be worth a call to one to pick their brain on getting the right fitting. Never know might get lucky and they have done it before Alternatively what about a fitting place? Something like Enzed who do hose and fittings, it may not be something they cater for but only the cost of a phone call to find out. Last I remember they did high pressure hydraulics, fuel and air lines etc.