Using tanks with no VIP/ Hydro?

[reefrat]

I live and dive in a place (TCI) where there is no actual requirement to do VIP’s or hydro’s on tanks and no facilities or qualified personnel to do them even if I wanted to! The local dive operators tell me that they take a peep inside their AL 80 tanks every now and then with a light and generally change them out after about 10 years of constant usage.
I own six AL80’s that I fill with my own compressor to 3000 psi for our private use and they are in good shape, never had a drop of water in them. Some of the older ones have bubbled and peeling paint on the outside and they range in age from ten years old to a few months old.
Is what I (we) are doing here genuinely unsafe or reasonable under the circumstances?

 

[captain]

I have gone for many 5 year cycles without hydros on my steel 72’s. I like you would look inside yearly for signs of water. I can’t speak for aluminum but I feel it is safe if you know the history of the tanks. If I bought a used tank I would get it tested then don’t worry about it after that. I have steel 72’s that are over 60 years old.

 

[Scared Silly]

I think the key is knowing the cylinder's history. If I could not get a hydro but was able to get fills and could peek inside regularly missing a requal hydro would not bother me.

 

[Rred]

Reefrat-
As long as you stay aware of your tanks' usage and condition, inside and out, there's nothing unreasonable. One could argue that for a recreational diver, one hydro per year is excessive, since tanks are built and tested for 100,000 uses, which is way beyond what one recreational diver is likely to ever put on them. But checking inside and knowing how to do a competent VIP...I'd argue that once a year is a good compromise, and if you don't know your fill source, twice a year might not be unreasonable. If you were traveling someplace and had your tanks filled by ten shops over the course of a year? I'd expect you to find something in the tanks needed cleaning. Contamination seems to be that popular.
As long as you are in control, and comfortable with the amount of degradation that might or might not happen...apparently you're legal. (Of course, if a couple of tanks go BOOM and tourism suffers, you may find the laws change too. The world seems to work that way.)

 

[rjack321]

I have had ali tanks fail hydro. It happens. Although if you are doing vips at least annually and replacing every 10 years I think you are pretty good. That said, when they fail they can often kill someone. So if you are skipping hydros because there is no place to even do them, I would be pretty conservative on the VIPs and replacements.

 

[Rred]

"I have had ali tanks fail hydro."
Particulars on that? Commercial use? Internal corrosion? Pressure test failed?

 

[reefrat]

The only “VIP” I can do is an informal look inside the tank with a thin flashlight. I might be able to see a significant crack or something but basically I just look to see if there is any water ingress (there never has been). So far the inside of all tanks looks like it does when new- shiny aluminum.
I am thinking that the 10 year old ones will be decommissioned and replaced with new, even though they look good!

 

[Scared Silly]

On a trip back to the states toss the older ones into you luggage and sell them state side.

Also look into taking a cylinder inspection course.

An inspection light is cheap. Tobin at DSS made a simple one a while back that is great. It is just a bare bulb on the end of a cord connected to a transformer. Not sure if he still has any.

 

[rjack321]

"I have had ali tanks fail hydro."
Particulars on that? Commercial use? Internal corrosion? Pressure test failed?

Failed VIP from pits and corrosion, internal and external (not the same cylinder, I think I have failed 3 in 15 years). Expoy paint is terrible at hiding corrosion and letting salt sit on the exterior surface.
Failed on permanent expansion, two different cylinders in 25 years
Just personal use, not overfilled or anything. I don't consider a hot fill to 3200psi that cools to 3000 overfilling (and neither does USDOT)

Cylinders sometimes decide to do weird things and need to be removed from service.

 

[rjack321]

The only “VIP” I can do is an informal look inside the tank with a thin flashlight. I might be able to see a significant crack or something but basically I just look to see if there is any water ingress (there never has been). So far the inside of all tanks looks like it does when new- shiny aluminum.
I am thinking that the 10 year old ones will be decommissioned and replaced with new, even though they look good!

Why not get the tools and training to do it right?