Using Hog 1st stage to drive booster pump

[RayfromTX]

I had one with almost similar specs (10 cfm at 110psi if I recall). Worked well for filling RB cylinders and even boosting into single 40s and 80s. Anything more than that and I had to watch that I didn't run it too long continously.

Thank you. I am considering a backup fan and will switch to synthetic oil after 50 hours of breakin time. I'm thinking a continuous run of 45 minutes would be pushing it except in the coolest of conditions. Would you agree?

 

[nadwidny]

Thank you. I am considering a backup fan and will switch to synthetic oil after 50 hours of breakin time. I'm thinking a continuous run of 45 minutes would be pushing it except in the coolest of conditions. Would you agree?

With mine I went 10ish on 5 off. Possibly too conservative.

 

[RayfromTX]

@RayfromTX how much helium are you planning on using? You don't want to pump 12/70 through them, but 21/35 is fine. I have buddies that have done it on a Rix SA6 for years, pumped thousands of cubic feet through it, and have 0 issues with it. The key is keeping it cool. They use a supplemental window box fan when pumping anything since it's hot *in Carolinas, now Houston*, but it works just fine.

The important part of this though is that you really want to be banking EAN32 for all of this. If you subscribe to standard gasses, which in my opinion you should, then all of your trimix comes from EAN32, and it will save your booster when making 50/50.

In that case, you won't be needing your booster until you start doing accelerated decompression and you'll be doing pretty low amounts of use on your booster. For that, I would put a valve going to that cheap welding regulator, and cut it out of the loop until you are done filling your backgas, once that happens, the banks will be lower than 4500psi, and you can open the valve to drive the booster. Compressor won't be able to keep up so it won't get up to working pressure of the banks and you'll be fine. The regulator should be perfectly fine with 300 bar pressures, it's just the gauge that will be very upset and not work properly if you overpressure it.

Thanks several times Tbone

This post has lingered in the back of my mind for the last few weeks as I contemplated all the oxygen cleaning I would be obligated to do. Since this is set up in my house, I have been worrying a lot. I've been reading the oxyhacker and just thinking.....

I've decided to take another step and set up a continuous blender and use my bank for EAN32. It just took me a while to get there in my mind but it makes sense. I'm still thinking to boost the helium PP into my tanks through my panel and I'll limit the bank pressure to some number in the 3,200 range. I'm not sure about the deco tanks in the future but that is another bridge for another day.

Thanks all for your help. I hate when threads die without resolution. I'll keep this one updated. I know, everybody says that.

 

[tbone1004]

@RayfromTX glad it helped. Why limit the bank pressure to 3200?

 

[RayfromTX]

What would you feel ok pumping 32% to through an SA-6? I'm reading 3,200 to 3,400. Most of the mixes I've looked at only need the banked gas to the low to mid 2s and boost helium and a little air on top.

 

[tbone1004]

What would you feel ok pumping 32% to through an SA-6? I'm reading 3,200 to 3,400. Most of the mixes I've looked at only need the banked gas to the low to mid 2s and boost helium and a little air on top.

a buddy runs his to about 4500 and has for years. Think about it this way. The third stage in your Rix is compressing things to 4500psi anyway because that is the outlet pressure. If you are running EAN32 through it, then you are compressing it to 4500psi, so there is no issue banking it to that pressure other than compressor wear and tear from running at max pressure due to it being slight out of balance
Rix is going to say not to continuous blend through their compressors, but then again, neither does anyone else....

 

[RayfromTX]

What I remember has to do with the safety of pressurizing high PPo2. It seems there is a consensus about the safety of <ean40 but only up to a reasonable pressure. I'll find some links instead of relying on my memory. It has failed me in the past a time or two and I could be confusing pure o2 pressures with nitrox pressures.

 

[tbone1004]

What I have read has to do with the safety of pressurizing high PPo2. It seems there is a consensus about the safety of <ean40 but only up to a reasonable pressure. I'll find some links instead of relying on my memory.

in cave country the banks of EAN32 are kept at 5k psi or higher if they have 6k compressors. They have been doing this for decades with no issues. We regularly fill to close to 4k in the bottles, again with no issues...

 

[RayfromTX]

I edited my post. Thanks for your help.

 

[tbone1004]

I edited my post. Thanks for your help.

it depends on what order you fill. If you fill He first you save stress on your shop compressor and booster and put a bit more on your Rix. If you fill the other way around, you put a lot more stress on the shop compressor and booster but keep it low on the Rix. I'm personally in the Helium first and top off camp