For you "I fill my own tanks" PSA

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grackleblast

grackleblast

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Jan 8, 2017
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North Carolina, United States
I don't want to come across as too preachy here , but it needs to be mentioned again and again ...............................control the moisture output to your tank or airgun..............

Compressing air extracts any and all moisture from it.............WATER............... Unfortunately , water and highly compressed air = BAD MOJO for the aluminum liner in your tank and

airgun . I have purchased and sold a bunch of tanks and always remove the valve and take a peek inside. If it looks sparkling new and shiny , we're full steam ahead . Should there

be any oxidation (rust) or signs of contaminates...........a no - go . So far the only issues I have found are moisture contamination in a couple of tanks.............they will not be sold...

The liner is the vessel that contains the compressed air , the carbon fiber wrap is what keeps the liner from becoming an overstretched balloon and rupturing . This is why you never

read about exploding carbon fiber tanks , only on occasion an aluminum tank.......a couple of years ago. So my lesson is to control the moisture and keep your tank and airgun happy

and functioning the way that you expect . Lesson over . Here's one tank that is now a paperweight..........

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Totally agree, 120%. Got into airguning last year and after getting water into my big bore twice, I've maybe went a bit overboard on filtration. But not getting any now.
1st is centrical filter, 2nd has color changing silica beads, 3rd has moleculer seave.
I'd rather have a the longer run time filling the filters verses cleaning out the gun or tank. Or creating a bomb thru the negligence of not doing that little bit extra.
Was shooting on my range this morning after it rained overnight, obviously lots of moisture still in the air, but no worries. Checked silica beads after coming in and barely any change in 1st 1/2 inch after shooting 100 rounds.

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Good for you , and you are not creating a "bomb" by introducing moisture into the tank . What will happen over time is that as the liner corrodes , the it will eventually leak. The tank will not explode or create any danger.................it just won't be airtight ...............and after all , that's what we seek >
 
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I have never had a drop of air / a mist of air come out of my fill bottles, i often turn them upside down and open the valve to see if there are any air in there.
Also never seen any form of moisture or dirt in the pipe tanks on my Cyclone and lately Epic Two rifles that i have had apart.
Changing valve / valve / fill station on my 9L tank i did stick a bore scope down inside it, and saw what i would assume a bottle should look like on the inside, but this 9L bottle also only seen 1 year of use until now.
So bottles filled by dive shop.
Bottle filled by Viking airgunner.
And now bottles filled by myself, have no moisture.

Mind you looking at the valve on the #4 stage of my compressor clearly indicate that something pass by there, this something also find its way to the vapour trap on my compressor, but the drain on the filter just have air coming out when i "drain " it during fills.

Stage #4 return valve spring after 20 hours of use.

Return valve spring.jpg
 
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DNF said:
I’m pretty sure any “water” doesn’t remain liquid under pressure. I don’t think turning it upside down and opening valve and not getting water out is an indicator of dry air.
Might be wrong but I don’t think that’s how that works.
Click to expand...
It doesn't. There is also the condensation created from ambient when compressed air is released. The appearance of "mist" when degassing does not mean there was moisture in the tank. Very cold air hitting ambient air will create that mist.
 
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I can agree that moisture in your air tank is bad, but where would you be seeing rust? The aluminum liner does not rust. It will oxidize, but that oxidation layer just creates a protective layer for the rest of the aluminum. Brass parts will tarnish, but not rust as well..

I'm assuming you are referring to other smaller parts that contain iron of some level that can rust over time?
 
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grackleblast said:
I don't want to come across as too preachy here , but it needs to be mentioned again and again ...............................control the moisture output to your tank or airgun..............

Compressing air extracts any and all moisture from it.............WATER............... Unfortunately , water and highly compressed air = BAD MOJO for the aluminum liner in your tank and

airgun . I have purchased and sold a bunch of tanks and always remove the valve and take a peek inside. If it looks sparkling new and shiny , we're full steam ahead . Should there

be any oxidation (rust) or signs of contaminates...........a no - go . So far the only issues I have found are moisture contamination in a couple of tanks.............they will not be sold...

The liner is the vessel that contains the compressed air , the carbon fiber wrap is what keeps the liner from becoming an overstretched balloon and rupturing . This is why you never

read about exploding carbon fiber tanks , only on occasion an aluminum tank.......a couple of years ago. So my lesson is to control the moisture and keep your tank and airgun happy

and functioning the way that you expect . Lesson over . Here's one tank that is now a paperweight..........

View attachment 560202View attachment 560203View attachment 560204View attachment 560205
Click to expand...
Like your lighting solution .
 
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I don't totally understand why or how water in high pressure vessels damages them but the pressure enhances the normal oxidation of aluminum which makes the oxide layer and also hydrogen gas. So the oxide layer is not protective enough at high pressure and the oxidation continues.

The way the water gets into the bottle is not a mystery. Our compressors raise the pressure (that's their job) and the ability of the oxygen in the air to carry moisture goes down with pressure but up with temperature. So at the outlet of the compressor there is still more moisture than the air can support because the temperature is elevated. When the air cools, the moisture comes out. So we filter the air to reduce the moisture so it does not come out of the oxygen at room temperature. One way the filter removes moisture is just condensation. The filter is relatively cool so it reduces the air temperature and moisture comes out. Additional moisture is trapped in absorbent media and dessicant.

Nitrogen works because it does not transport moisture.
 
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JimD said:
I don't totally understand why or how water in high pressure vessels damages them but the pressure enhances the normal oxidation of aluminum which makes the oxide layer and also hydrogen gas. So the oxide layer is not protective enough at high pressure and the oxidation continues.

The way the water gets into the bottle is not a mystery. Our compressors raise the pressure (that's their job) and the ability of the oxygen in the air to carry moisture goes down with pressure but up with temperature. So at the outlet of the compressor there is still more moisture than the air can support because the temperature is elevated. When the air cools, the moisture comes out. So we filter the air to reduce the moisture so it does not come out of the oxygen at room temperature. One way the filter removes moisture is just condensation. The filter is relatively cool so it reduces the air temperature and moisture comes out. Additional moisture is trapped in absorbent media and dessicant.

Nitrogen works because it does not transport moisture.
Click to expand...
Yes, the oxidation of aluminum creates a negligible amount hydrogen gas. For an air rifle anyway. If you are filling an aluminum scuba tank, you don't want any aluminum oxidation as you would be breathing the hydrogen.

The only information or evidence that high pressure enhances the normal oxidation that would change the oxidation properties is with high temperature as well. I'm wondering what kind of testing has been done (if any) to determine how many fills an PCP tank of a given size it takes to cause issues of any kind. Even if there is a extremely small amount of moisture introduced to the tank each time. It would have to be done in a controlled environment (temp, humidity, altitude, barometric pressure, etc.) and the same filling process an equipment.

It would be nice to be able to have a safe, reliable, easy to come by source or clean moisture-free, clean air for a PCP. It seems that nitrogen rifles solves issues with moisture and being a cleaner gas, but could also introduce some safety concerns if there is a leak.

With all of that said, I've seen some pretty neat setups members have hear to combat the moisture issue. I've been looking into the alpha filter to pull the moisture out during fills. Anyone here have experience with them?
 
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shakezoola said:
Yes, the oxidation of aluminum creates a negligible amount hydrogen gas. For an air rifle anyway. If you are filling an aluminum scuba tank, you don't want any aluminum oxidation as you would be breathing the hydrogen.

The only information or evidence that high pressure enhances the normal oxidation that would change the oxidation properties is with high temperature as well. I'm wondering what kind of testing has been done (if any) to determine how many fills an PCP tank of a given size it takes to cause issues of any kind. Even if there is a extremely small amount of moisture introduced to the tank each time. It would have to be done in a controlled environment (temp, humidity, altitude, barometric pressure, etc.) and the same filling process an equipment.

It would be nice to be able to have a safe, reliable, easy to come by source or clean moisture-free, clean air for a PCP. It seems that nitrogen rifles solves issues with moisture and being a cleaner gas, but could also introduce some safety concerns if there is a leak.

With all of that said, I've seen some pretty neat setups members have hear to combat the moisture issue. I've been looking into the alpha filter to pull the moisture out during fills. Anyone here have experience with them?
Click to expand...
What safety concerns with a nitrogen leak ?
 
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shakezoola said:
Well, according to the inter-webs... Nitrogen gas can displace oxygen. Depending on where and how much is leaked it could cause asphyxiation. I also read that a leaking nitrogen tank can become unstable and rapid expansion could rupture a tank.
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I believe tank ruptures only occur with liquid nitrogen conversion to gaseous nitrogen.

We do not use liquid nitrogen.
 
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79% of the air we breathe is nitrogen. It is totally safe and is the perfect solution to our moisture problem. Unfortunately, it has gotten too expensive for us around here. Our local gas supply company has been bought out by a big national chain and the guy who used to give us a good deal on it told us that he can no longer help us out. I hate it but that’s the way the world is now. To those who can get a decent deal on it, it’s the only way to go.
 
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shakezoola said:
It would be nice to be able to have a safe, reliable, easy to come by source or clean moisture-free, clean air for a PCP. It seems that nitrogen rifles solves issues with moisture and being a cleaner gas, but could also introduce some safety concerns if there is a leak.

With all of that said, I've seen some pretty neat setups members have hear to combat the moisture issue. I've been looking into the alpha filter to pull the moisture out during fills. Anyone here have experience with them?
Click to expand...
Adding a desiccant filter to any compressor makes for a safe, reliable, easy to come by source of clean moisture-free clean air. The Alpha will work, as will most other brands too. My compressor is s Shoebox so I filter before the compressor, but if I were looking to buy a post compression filter and wanted something better than the simple Tuxing style ones availabe on Amazon or other places, I would probably go with the one from Nuvair: https://nuvair.com/personal-filter-din.html
 
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