Boosting

[aknelsonone]

Would like to know how everybody is filling their RB tanks. Anyone owning a Booster pump ? Or just trans filling from larger tanks?

Cheers Andreas

[john j]

I'm using boosters.  I use the Jetsam Technology "baby booster".  I also have a two-stage haskel that I use to feed the baby booster enabling me to use all but 100 PSI from a source tank. The baby booster doesn't do much once the source tank falls below 600 PSI. 

If I could do it all over again, I'd buy the Jetsam "microbooster" which is an electrically driven booster pump that has higher throughput than the baby booster and you don't need an air compressor to run it.  It just plugs in to a 120 volt outlet.  Very nice.

Jetsam has been good to me-they stand behind their products and repair costs are quite reasonable.




Many of the CCR people I know are just trans filling unless they have some special long road trip to a remote location.  In that case, they will go to a shop that has a booster and get their tanks completely full.  If they are flying somewhere, they can't do that of course. 

Some folks never use boosters-they just have their old OC tanks filled with oxygen or diluents and trans fill in the field or they trans fill at whatever dive shop they can find at their destination.

I love my boosters, but they are not cheap and they have, on occasion, failed when I needed them most.  I never completely count on a booster to work, so I always have a backup tank filling plan if I am on an important dive trip.

[aknelsonone]

I love my boosters, but they are not cheap and they have, on occasion, failed when I needed them most.  I never completely count on a booster to work, so I always have a backup tank filling plan if I am on an important dive trip.

John,
Thanks for the replay. I have done some of the trans-filling and  learned pretty quick this not a good way to go. It might not count since I used relative small cylinders in trans filling.
Back to what you mentioned above what did fail that the Baby Booster did not work? Issues with the check valve sets?
I did some research and collected quite some info about the Boosters we can get locally and there are at least four different manufacturers. I did not look closer at the Jetsam model. At the moment the Haskel 4AG25 (MSB9000) is the favorite regarding price and value.
Maxtor is a affordable but small machine. The Hydraulics International and the Jetsam I found affordable but with references about mechanical issues. The Haskel is clearly the largest of all three with 1.2 cuin
What I have not tackled is were to get the hoses and fittings locally. I know a few places to get fill whips but price value ratio is most of the times at odd.

Any suggestions to the whips?

Regards,  Andreas

[john j]

Regarding the failures on the baby booster.  The first failure I had was a worn our check valve.  I had spare parts and fixed that easily in a few minutes.  The second problem I had was that the pump locked up.  I sent it back and they had to replace the piston, cylinder sleeve and all the valves.  For some reason, it just jammed up and severly damaged itself.  I filter the gas going in, so I don't think I got a piece of sand or other particle in there.  I have no explanation for that problem.  The total bill for that repair including shipping from Canada was only about $130.00, which I thought was quite reasonable considering that they replaced almost all of the internal components of the pump.

Regarding fill whips, I avoid buying fittings and hoses from diving places whenever possible because they are too expensive and many times inferior quality to what I can get for industrial applications.  Some things like yoke and DIN fittings are only sold through dive shops, so you have to go that route on those.  However, many of the fill whips sold through dive shops have carbon steel ends.  These always rust inside and are thus a major oxygen fire hazard because they send rust particles through all your valves and fittings.  For whips, I use electrically conductive CNG (compressed natural gas)  hose with stainless steel ends.  I get that through a local Parker distributor called Quest Engineering.  This hose is custom made with whatever ends you ask for.  I get stainless steel 1/4 male NPT ends with strain releif.  However, you must special order such that they do not use any lubricant when they make up your hose assemblies.  They will gladly do that but you have to ask for it specifically.  If you do not ask for that, they will use hydrocarbon oil as a lubricant when they make up your hoses and there will be lubricant trapped on the barb inside the hose fitting.  You will find that unpleasant when you pump oxygen through it.  The CNG hose is super tuff and lasts for years-it absolutely blows away anything I have ever seen from the dive industry and Parker Engineers approved it for my application, so I trust that it is OK for what I am doing.

For things like gauges and pipe thread fittings, I also get them from Parker via Quest Engineering.  I like brass fittings because stainless steel threaded to another stainless steel fitting tends to gall during assembly if it has been cleaned for oxygen service.  What I mean by "gall" is that the threads cold-weld together and you can't ever get them apart again.  I have tried to find an effective oxygen compatible anti-galling agent but I don't think there is one.  I dont really like pipe threads becasue they are hard to get gas tight and they always create metal shavings when they are assembled (not the best for oxygen applications), but they are so much cheaper than the alternatives, that I give in and use them. 

I don't have part numbers with me right now, but if you want more detail, I would be glad to provide it.

[john j]

Attached are photos of my baby booster, fittings and whips.  I have used male and female DIN fittings all over to make the system modular, so components can be intermixed or attached to each other without any tools other than a wrench for attaching the CGA fittings to the supply tanks.  This provides maximum flexibility in the field.  I can quickly connect components together in whatever mixed up fashion I need to get the job done and I don't have to make and break pipe thread fittings to change the setup.  Pipe threads create lots of metal shavings every time they are turned and that is very bad for oxygen systems.  I also incorporate filters upstream of valves and at the input of the booster to capture particles that can damage these components. 

Some folks use hydraulic quick coupler fittings so they can disconnect things fast.  These were designed for pressurized liquids, not gases.  In my opinion, that is very dangerous.  If they ever break loose under pressure (which I have seen them do), they will fly off with incredible force.  If you want a "quick coupler", use a male and female DIN fitting.

The photo of the hose shows the stainless steel crimped hose ends that Parker can provide.

None of these fittings or hoses were cheap, but they have worked flawlessly for years.  The only failures I have had were with the booster itself as I described previously and one time I broke a digital pressure gauge when I dropped it.  That was my fault though.

I hope this helps;

Regards;

John

[aknelsonone]

John,
Thank you for the hint with the din connectors this gives some directions. I have the source for the DIN coupler. But have not decided nor finished search for the source of the hoses.

Andreas

[rcojr]

This summer I built a booster using directions from the Oxy Hacker book.
I bought 60 inch braided 5000 psi stainless steel oxygen hoses from my local gas supplier. (Oxygen Service Company)
Bob

[aknelsonone]

Attached a picture how I got along with the booster project.
The project started by getting the 4AG25 booster. What is the biggest challenge is getting the connectors and the Hardware.
A starting point for many of us is trans-filling. This method is widespread and most of the stores filling Nitrox are trans-filling.
However the big disadvantage is you need a high and low pressure gas source. This to fill your tank efficiently.
Once done the trans-filling you will get to the conclusion, there is another way... and a faster way....

The tool has save some trips to the store.
The shop compressor has to run around 140 psi to get to 3000psi. The adaptor for the low pressure air allows to connect an inflator hose. Therefore the "Magic toolbox" is protable and allows to refill tanks anyplace. However you will need a drive gas source.
DIN adaptors are used for all connections. I used the same concept like John J. uses above.

My local welding shop was very helpful getting not only gases but also the hardware. The Hardware is all SS and O2 clean. With the fun of building and owning such equipment there is also learning about the how-to. 
The DIN fittings are all from GMC other hardware Swaglok, Western Enterprise, Decker etc.


Andreas