Booster Pumps

[I Dive Solo]

Can somebody please explain to me why all Air/O2 booster pumps, (apart from one Russian one) are powered by air.

I guess that there is a good sensible reason for it. But what is it?

If I am wrong and some are made that use another power source, a few pointers in the right direction would be appreciated.

Thanks a lot

[Chris aka divingchef]

Can somebody please explain to me why all Air/O2 booster pumps, (apart from one Russian one) are powered by air.

I guess that there is a good sensible reason for it. But what is it?

If I am wrong and some are made that use another power source, a few pointers in the right direction would be appreciated.

Thanks a lot

Itīs to reduce the chance of a spark causing an explosion.
A small spark in an 100%O2 environment will make quite a flame !!

And yes as far as I am aware there are air and manual powered booster pumps,,,,petrol is defiantly a no-no:)

Chris

[Chris Cherrington]

The KISS rebreather guys do an electric one, but its small capacity IIRC.

Chris

[iain/hsm]

Can somebody please explain to me why all Air/O2 booster pumps, (apart from one Russian one) are powered by air.
I guess that there is a good sensible reason for it. But what is it?
If I am wrong and some are made that use another power source, a few pointers in the right direction would be appreciated.
Thanks a lot

In a word I suppose you should say there not. Most industrial, commercial and offshore diving units including some dive shops use electrical driven units that plug into 3 pin 240 volt domestic sockets.

The photo enclosed shows a typical two stage high pressure 350 bar booster pump driven with a small 240 volt single phase 2HP motor domestic socket. At 500 rpm with an average supply pressure the charging rate is 16 cu foot/min and would fill a 3L from 100 bar to 232 bar in less than 1 minute, (hence why a bank is normally used) or the RPM is lowered for oxygen. Electrical running cost is negligible when compared to the most inefficient air driven motors hence why they are used mostly in professional diving.

[Janos]

In a word I suppose you should say there not. Most industrial, commercial and offshore diving units including some dive shops use electrical driven units that plug into 3 pin 240 volt domestic sockets.

The photo enclosed shows a typical two stage high pressure 350 bar booster pump driven with a small 240 volt single phase 2HP motor domestic socket. At 500 rpm with an average supply pressure the charging rate is 16 cu foot/min and would fill a 3L from 100 bar to 232 bar in less than 1 minute, (hence why a bank is normally used) or the RPM is lowered for oxygen. Electrical running cost is negligible when compared to the most inefficient air driven motors hence why they are used mostly in professional diving.

Not particularly portable though is it? :D:D:D

The Jetsam air powered booster weighs 3kg, their electric version weighs 33kg.

I'd like a booster, but for the diving I do, the time I'd spend getting it serviced, and servicing the compressor I'd have to get to supply it with drive gas isn't worth it. I just have a few J's of premix, O2, and one of air (for my suit) in the shed.

Janos

[iain/hsm]

Not particularly portable though is it? :D:D:D
(edit)
Janos

Sorry didnt read anything about portable in dive solo's post. My revised post: a smaller "Portable electrical" at 20 kg unit, Using a 1/2HP motor and still plugs into that domestic 3 pin socket.:p
Model Microboost: Fully automatic, auto stop, complete with high pressure cut off switch, HP/IP safety relief valves, 2mu inlet micronic filters, high temeprature safety RTD cut out (high temp).

[I Dive Solo]

Sorry didnt read anything about portable in dive solo's post. My revised post: a smaller "Portable electrical" at 20 kg unit, Using a 1/2HP motor and still plugs into that domestic 3 pin socket.:p
Model Microboost: Fully automatic, auto stop, complete with high pressure cut off switch, HP/IP safety relief valves, 2mu inlet micronic filters, high temeprature safety RTD cut out (high temp).

Iain/hsm
Are you associated with microboost? If so can you advise if it can be used for boosting Nitrox ( max 40%) to approx 200bar?

[Janos]

Sorry didnt read anything about portable in dive solo's post. My revised post: a smaller "Portable electrical" at 20 kg unit, Using a 1/2HP motor and still plugs into that domestic 3 pin socket.:p
Model Microboost: Fully automatic, auto stop, complete with high pressure cut off switch, HP/IP safety relief valves, 2mu inlet micronic filters, high temeprature safety RTD cut out (high temp).

And CE marked no doubt :D

Just out of interest, but do you know how much the Microboost is? (I'm not seriously interested as decanting means I don't have to worry about getting compressors or boosters serviced)

Janos

[Nigel Hewitt]

To drive my Haskell takes a 10hp air compressor and the Haskell has no problem catching up with the supply even with the motor running.
Compressing gasses uses an incredible amount of power and a simple piston does the job very efficiently.

[Beanie]

And CE marked no doubt :D

Just out of interest, but do you know how much the Microboost is? (I'm not seriously interested as decanting means I don't have to worry about getting compressors or boosters serviced)

Janos
Not cheap I guess as its Rix ;)

Would be interested to know though

[iain/hsm]

To drive my Haskell takes a 10hp air compressor and the Haskell has no problem catching up with the supply even with the motor running.
Compressing gasses uses an incredible amount of power and a simple piston does the job very efficiently.

An interesting point there Nigel, as there is little or no written direct comparison charts of air driven against electrical driven boosters. In fact it is very difficult to get in writing the amount of drive air consumed with low supply gas pressure ranges. Your example needing a 10HP low pressure air supply to drive your air driven booster is still less than the pump needs for full capacity but what are the charging rates how long, what start pressure, how big the cylinder. For example a Haskel AGT 15/30 can consume up to 90 cu ft per minute to produce 15 scfm, you would need a road drill compressor to keep up. Something an electrical pump will produce with a 2HP motor.

[Nigel Hewitt]

Something an electrical pump will produce with a 2HP motor.We have to be careful here.
Boosting is so hugely dependent on the supply pressure.
15cuft/min is a big butch compressor going from 1bar but topping off a 232 tank from a 180bar J is nothing like that.

The problem is that you junk so much energy as heat it's impossible to do much of a power comparison chart which is probably why nobody bothers. I once roughed up the stored energy in a 12L/232 as 1.2Mjoules but my compressor keeps the shed nice and warm so I bet I pay the electricity company for three times that at least.

[I Dive Solo]

Thanks divers for your input.
Perhaps I have asked the wrong question when I asked about the power source as I really needed to find out how many pulses per minute a booster normally makes. I realise (think) that the pulse rate will slow as the output pressure increases but at least it will give me a starting point if I decide to build one myself using an electrical power source.

If any of you that have one would time the Pulse per min and pass it on I would appreciate it.
Thanks