Have a question about tank vis inspection

[Texasguy]

Well, it is more about air than the visual inspection.

Say, when the visual inspection is done. The tech puts a valve on the tank. There is some regular air with some moisture in the tank at this point.

I guess a tech puts compressed dry air inside after. Thus, what happens to the moister that is initially in the tank due to non-dry air in the bottle?

Just curious if it gets extracted some way or it is ignored?

 

[boulderjohn]

Well, it is more about air than the visual inspection.

Say, when the visual inspection is done. The tech puts a valve on the tank. There is some regular air with some moisture in the tank at this point.

I guess a tech puts compressed dry air inside after. Thus, what happens to the moister that is initially in the tank due to non-dry air in the bottle?

Just curious if it gets extracted some way or it is ignored?

When you fill the tank with dry compressed air, the percentage of moisture already in that tank drops from a very small amount to a truly miniscule level. When you use the tank, almost all of it leaves. Every time you refill it, the percentage drops even more.

 

[Wookie]

I ignore it. The air I add is way less than the dewpoint of the ambient air in the tank, and what is in the tank is a small fraction of the total air when the cylinder is filled. I am very careful with cylinders left at ambient pressure, but not if I will fill them right away.

Edit. Yeah, what he said^^^

 

[Scubatude]

We have a secret way of extracting all the moist air. It is only available at Scubatude and we charge extra for it.

 

[Scared Silly]

I create a hermetic seal and hook the cylinder up to a vacuum to remove the air. It then filled to 100 bsi and purged three times. Once completed, I refill the cylinder. I thought that was standard? Are shops doing something different????

 

[Scubatude]

So much for my secret.

 

[spectrum]

Some will have an air hose that they insert to flood or purge the tank with dry scuba air, add the valve and fill. In general dilution is the solution with the fill against the base volume ratio being on the order of 200:1

Pete

 

[oldschoolto]

I assemble the tank in an autoclave in a total vacuum...

Jim...

 

[WarrenZ]

I live in the desert so there is no humidity to keep out of the tank. I just spin the valve on and fill.

 

[Chugwhump]

I assemble the tank in an autoclave in a total vacuum...

Jim...

I would like to see a picture of you in your vacuum suit while you are within the vacuum environment of your giganto autoclave, if this is not a trade seee-cret.
Or do you just wrap yourself in bubble wrap and hold your breath?

Chug
Opens them up, looks inside, closes them up, in humid SoFla.