bendyone
Well-Known Member
How many oz's of CO2 would you need to inflate a 9 foot avon dinghy. You can buy 20oz bottles for paint ball guns and maybe these could be used to infate a dinght in an emergency.
CO2 Inflation
- Thread starter bendyone
- Start date
ShipsWoofy
Well-Known Member
Years ago my next door neighbour who was a keen diver decided to pump up his tender in his front garden. Obviously foot pumps are for jessies. He held a dive bottle 'near' the valve and opened it slightly.
I would say the dinghy was up in a second!
Realising that dive bottles are under massive pressure, it still suggests not very big at all. He only aimed the bottle outlet at the valve, not stuffed it in to make a seal.
The difficult bit would be having exactly the right amount of air / co2 as your method would be to fill the dinghy without blowing it to pieces with the bottle connected to the valve directly. Do liferafts have a dump valve to stop them exploding?
It is possible by the way, tinker used to sell a liferaft kit for their dinghies, they have recently stopped, I think because of H&S.
I would say the dinghy was up in a second!
Realising that dive bottles are under massive pressure, it still suggests not very big at all. He only aimed the bottle outlet at the valve, not stuffed it in to make a seal.
The difficult bit would be having exactly the right amount of air / co2 as your method would be to fill the dinghy without blowing it to pieces with the bottle connected to the valve directly. Do liferafts have a dump valve to stop them exploding?
It is possible by the way, tinker used to sell a liferaft kit for their dinghies, they have recently stopped, I think because of H&S.
steve_cronin
N/A
Expansion chamber required.....
...in the line otherwise you could be squirting liquid gas into the raft which will immediately freeze the fabric and make it liable to crack or even shatter into small pieces.
There is no arguement on this point. It happens; it HAS happened; I've done it.
I had a similar idea around ten years ago when there were a lot of spare CO2 extinguishers going around and I happened to notice that the outlet expansion trumpet's attachment nozzle had the same thread as a 1" pipe nozzle so one glorious April morning I connected it all up to an old inflatable and pulled the trigger. Result:- big pile of frost building rapidly on dinghy skin opposite inflation point then a sudden crack sound as the fabric did just that. End of experiment for ever.
Conclusion:- BUY A RAFT - just how much do you value you and your loved ones lives at anyway?
Steve Cronin
...in the line otherwise you could be squirting liquid gas into the raft which will immediately freeze the fabric and make it liable to crack or even shatter into small pieces.
There is no arguement on this point. It happens; it HAS happened; I've done it.
I had a similar idea around ten years ago when there were a lot of spare CO2 extinguishers going around and I happened to notice that the outlet expansion trumpet's attachment nozzle had the same thread as a 1" pipe nozzle so one glorious April morning I connected it all up to an old inflatable and pulled the trigger. Result:- big pile of frost building rapidly on dinghy skin opposite inflation point then a sudden crack sound as the fabric did just that. End of experiment for ever.
Conclusion:- BUY A RAFT - just how much do you value you and your loved ones lives at anyway?
Steve Cronin
Graham_Wright
Well-Known Member
Re: Expansion chamber required.....
So what do life rafts inflate with;- I thought that was CO2?
BTW, dive bottles are great for perking up the barbecue (with care!).
So what do life rafts inflate with;- I thought that was CO2?
BTW, dive bottles are great for perking up the barbecue (with care!).
steve_cronin
N/A
Re: Expansion chamber required.....
Yes but it goes through an expansion chamber and/or regulator first just like your Gaz blowlamp although in that particular case only a primitive regulator which is more of a constrictor. To get the comparative effect (but don't do this at home children!) put a match to an opened propane cylinder. You'll join the space race sooner than you thought possible.
Steve Cronin
Steve
Yes but it goes through an expansion chamber and/or regulator first just like your Gaz blowlamp although in that particular case only a primitive regulator which is more of a constrictor. To get the comparative effect (but don't do this at home children!) put a match to an opened propane cylinder. You'll join the space race sooner than you thought possible.
Steve Cronin
Steve
Rick
Well-Known Member
Re: Expansion chamber required.....
Even rafts freeze when people inflate them ashore - they depend on being in the water to prevent freezing the fabric on inflation.
Even rafts freeze when people inflate them ashore - they depend on being in the water to prevent freezing the fabric on inflation.
hmm
Well-Known Member
DOES THAT MEAN...
...that lifejackets (which have co2 inflation) are fitted with in line expansion chambers?
Would the original poster be able to therefore take one of the fittings off an old life jacket etc (as long as it is for a tender and not as someone said a liferaft).
By the way how do you remember the very old aircrew lifejackets which had a big (a foot long) air cylinder slung at the bottom? Did they have inline expansion chambers fitted.
Very interesting science here.
Glad you mentioned the freezing affect before the chap tried to experiment.
...that lifejackets (which have co2 inflation) are fitted with in line expansion chambers?
Would the original poster be able to therefore take one of the fittings off an old life jacket etc (as long as it is for a tender and not as someone said a liferaft).
By the way how do you remember the very old aircrew lifejackets which had a big (a foot long) air cylinder slung at the bottom? Did they have inline expansion chambers fitted.
Very interesting science here.
Glad you mentioned the freezing affect before the chap tried to experiment.
Drascomber
Well-Known Member
Re: DOES THAT MEAN...
Seriously though chaps, as I understand it, French regs say that if you go six miles off shore you must carry an automatically inflating dinghy.
Now if I kept life raft on the deck of my small boat I would seriously impair my boat's safety at sea - so auto inflation of very small dinghy sounds like a good plan. Is it a practical proposition to arrange something? Would a paint ball gun cylinder and an expansion chamber with a small orifice do the trick?
Seriously though chaps, as I understand it, French regs say that if you go six miles off shore you must carry an automatically inflating dinghy.
Now if I kept life raft on the deck of my small boat I would seriously impair my boat's safety at sea - so auto inflation of very small dinghy sounds like a good plan. Is it a practical proposition to arrange something? Would a paint ball gun cylinder and an expansion chamber with a small orifice do the trick?
