Cal Club Autocross Forums

I bought a small 20 lb tank and regulator for nitrogen.

Now I need to fill it somewhere.

Google is not helping so far.

Anyone have any advice on where to go near Redondo?

Thanks in advance....

Look for a welding supply shop.

Johnstone Supply or Grainger Supply.

Most places only do exchanges Pete. You'll probably have to say good-bye to your nice new tank. A welding supply would be your best bet if you want to keep the new one.

I know it sounds crazy but try Costco, they use nitrogen to fill tires.

http://www.airgas.com/" onclick="window.open(this.href);return false;

Arthur Grant wrote:I know it sounds crazy but try Costco, they use nitrogen to fill tires.

I checked there. They only have normal pressures i.e. 80-90 psi.
I need 4500 psi

Going to call around on Tues. for welding supply spots near me.

Sims Welding supply looks promising.

What about this place: http://air-source.com/" onclick="window.open(this.href);return false;

Not too far from you.

Pete Loney wrote:

Arthur Grant wrote:I know it sounds crazy but try Costco, they use nitrogen to fill tires.

I checked there. They only have normal pressures i.e. 80-90 psi.
I need 4500 psi

Going to call around on Tues. for welding supply spots near me.

Sims Welding supply looks promising.

Normally tanks are charged to approximately 2500 PSI. I'm not into physics or engineering, but I would think that compressing a bottle much higher than that would diminish the liquid/gas safety buffer to the point of it being unsafe. Another warning Pete, safe handling is critical. If somehow the valve breaks off, the resulting missile could knock the wind out of you......or kill you. Maybe some of our engineering types can chime in and give us all a safety briefing.

George Schilling wrote:

Pete Loney wrote:

Arthur Grant wrote:I know it sounds crazy but try Costco, they use nitrogen to fill tires.

I checked there. They only have normal pressures i.e. 80-90 psi.
I need 4500 psi

Going to call around on Tues. for welding supply spots near me.

Sims Welding supply looks promising.

Normally tanks are charged to approximately 2500 PSI. I'm not into physics or engineering, but I would think that compressing a bottle much higher than that would diminish the liquid/gas safety buffer to the point of it being unsafe. Another warning Pete, safe handling is critical. If somehow the valve breaks off, the resulting missile could knock the wind out of you......or kill you. Maybe some of our engineering types can chime in and give us all a safety briefing.

I actually used to carry around a compressed air tank with a max pressure of 4500 PSI while playing paintball.
It was made of fiberglass if I recall.

This tank is HEAVY duty. When I unpacked it on my carpet, I set it down without the stand and turned my head for a sec. and OWWWWW, it fell on the top of my foot.

Here is what I bought.

http://www.harborfreight.com/nitrogen-t ... 97061.html" onclick="window.open(this.href);return false;

NOT made in China. Made in good old SoCal.

I'll ask around when I get to the refill spot.
The safety info. with the tank was pretty good. No temps over 120 for storage was one of the items that stood out.

Solo Rules 1.3.2.L. Pressurized gas and air bottles with a pressure in excess of 200
psi must have a protective structure around their gauge and
valves.

typo????
from the HF specs: Max Pressure 450 PSI

I'll jump in here as well...... NO, NO, NO, that tank you bought is a max 450PSI which is typical for n-tanks used for tire inflation. That 4500psi tank is for guns (paintball) because it's being used in place of gunpowder! And like gunpowder, anything over 200 psi is pretty deadly in an accident. Hence rule 1.3.2.L. I'd be very careful around those pressures.

Steve caught it before I posted.

t

Tom Tanquary wrote:I'll jump in here as well...... NO, NO, NO, that tank you bought is a max 450PSI which is typical for n-tanks used for tire inflation. That 4500psi tank is for guns (paintball) because it's being used in place of gunpowder! And like gunpowder, anything over 200 psi is pretty deadly in an accident. Hence rule 1.3.2.L. I'd be very careful around those pressures.

Steve caught it before I posted.

t

Looks like the tank comes with a regulator that limits the maximum outlet pressure to 450 lbs. The tank itself would be filled to 2500 lbs when full and has a test pressure substantially higher than that. Filling it to only 450 lbs. defeats the purpose of having a nitrogen tank at all as at normal working temperatures, there will be little or no liquid in the tank to evaporate. This is where the engineers come in. I have no clue at what pressure the liquid will evaporate at normal air temperatures nor the curve at which the dew point changes with temperature. With a tank that small, unless it was pressurized to the point of at least some liquid, it would be no more useful than a larger air tank filled to 150 PSI.

The weak point it the brass valve. The problem I see with the tank pictured is that if dropped and the brass valve breaks off, it may become a missile. To be safe, the valve and regulator should be protected within a cage or the tank permanently mounted in a location that protects the valve and regulator from damage.

so what's wrong with filling a tank up to it's rated pressure?

When I was scuba diving a lot, IIRC we filled the tanks to about 3000 psi (rated for 4000 psi) and we did not have any rules about building any cage around the valve. Of course a multi stage compressor was required to get (any) gas up that high. We used a 4 stage in Saudi Arabia when I worked for Parsons Construction & Engineering (British Sub Aqua Club owned it). We were all qualified to run the compressor & fill tanks. Tanks were placed in a water barrel for safety when filling & to cool. We handled them carefully, but on a boat dive in choppy seas it was not unheard of for a tank to be dropped to the deck on it's valve. If you have ever taken one apart (I have) they are pretty damn heavy duty.

Having said that, it does not suprise me at all that SCCA would have a RULE about such things.

Steve Ekstrand wrote:typo????
from the HF specs: Max Pressure 450 PSI

Max. Output pressure from regulator is 450 psi. That part is adjustable from 0 to a max. of 450.

The other gauge, storage side, goes up to 5000 psi.

Pete Loney wrote:
Max.

Yes?

Max Hayter wrote:

Pete Loney wrote:
Max.

Yes?

Short for maximum you lug nut.

Well, shows you what I know.

Tom Tanquary wrote:I'll jump in here as well...... NO, NO, NO, that tank you bought is a max 450PSI which is typical for n-tanks used for tire inflation. That 4500psi tank is for guns (paintball) because it's being used in place of gunpowder! And like gunpowder, anything over 200 psi is pretty deadly in an accident. Hence rule 1.3.2.L. I'd be very careful around those pressures.

Steve caught it before I posted.

t

Paintball gun tanks have a regulator that controls and reduces the output down such that the Paintballs fly at 200 Feet per second or less.
Also, the gun itself has another regulator to fine tune the speed too.
You actually have to do a radar gun type speed check of your flying paintballs before every game basically.

Anything over 200 FPS REALLY F'ning hurt...especially in those special places like your neck and nads

Yeah, I got tank pressures and regulator pressures mixed up but the thought of pressures that high just seemed scary to me. My pelt gun does a 1000fps with just one pump so when you get up to the pressures we're talking about ....... blah, blah, blah.... it's my paranoid SSS side coming out. So one more thing for me to learn about.

;)