Hydro testing Carbon Fiber Tanks

[nomadicone]

I apologize for making this my first post but find myself in need of some information.

I purchased an Omega carbon fiber 4500psi tank a few years back and haven't been shooting much due to life getting in the way. When I looked at the manufactuer date it was a bit over 6 years old. I took it to a local dive shop that does hydro testing and they informed me it should be tested every three years and can only be tested three times before being taken out of service. I was under the understanding when I purchased, it needed to be tested every five years and after 15 years it should be taken out of service. Which is correct?

Mod Edit: Moved to Air Tanks, Pumps, Compressors and Filters forum

 

[T3PRanch]

Every 3 years and out of service for a public filling facility after 15 years from the "Born On Date" for Fiberglass and Kevlar Composite!

Luxfer Carbon Fiber Bottles are Hydro Tested every 5 years and out of service at 15!

Short answer: for DOT Carbon Fiber Wrapped Cylinders Hydro Test Every 5 years and service life is 15 years!

The Dive shop is certainly in error about the service life!

 

[Centercut]

5 years is correct. 

DOT standards state that tanks must be hydro’d every five years. At that time they will filled with water and pressurized to 5/3rds the tanks working pressure. (7500psi) They are held at that pressure for a predetermined amount of time, at least one minute. What they are looking for is tank wall expansion. It’s the REE number on your tank label. 

Omega tanks are standard CFFC tanks subject to the 5 year hydro requirement. 

 

[BigTinBoat]

Every 3 years and out of service for a public filling facility after 15 years from the "Born On Date" for Fiberglass and Kevlar Composite!

Luxfer Carbon Fiber Bottles are Hydro Tested every 5 years and out of service at 15!

Short answer: for DOT Carbon Fiber Wrapped Cylinders Hydro Test Every 5 years and service life is 15 years!

The Dive shop is certainly in error about the service life!

Thurmond,

SCUBA tanks need to be Hydro'd every 3 years and this is what dive shops normally deal with. They are in error about the CF being every 3yrs as opposed to every 5 years, but they would be correct on the life service. Remember he is not starting with a new tank, it's 6 years old. So add to that the 9 yrs (3 Hydro's at 3 yrs each) they are telling him and you get the 15yrs.

 

[nomadicone]

Actually he didn't know the age of the tank when he quoted the 3 hyro test rule as we were talking over the phone. Now I have another concern. Is he going to ding me for 2 hydo tests since the tank is 6 years old and he firmly believe it needs to be tested every 3 years. If so is that indicated on the tank or in some data base so I'm stuck even if I take it to another shop next time? I guess while I thought I was educated on these tanks until today.

 

[BigTinBoat]

Actually he didn't know the age of the tank when he quoted the 3 hyro test rule as we were talking over the phone. Now I have another concern. Is he going to ding me for 2 hydo tests since the tank is 6 years old and he firmly believe it needs to be tested every 3 years. If so is that indicated on the tank or in some data base so I'm stuck even if I take it to another shop next time? I guess while I thought I was educated on these tanks until today.

Look at your tank, it should be on the label. (or post pics of the tank here if you can't find it) I would take it to an actual Hydro tester 'cause that's all they are going to do is send it out. Look for Fire Service places they usually do them, or have good contacts.



Edit to add I thought he would have seen the tank since you posted " I took it to a local dive shop that does hydro testing........"

 

[T3PRanch]

Every 3 years and out of service for a public filling facility after 15 years from the "Born On Date" for Fiberglass and Kevlar Composite!

Luxfer Carbon Fiber Bottles are Hydro Tested every 5 years and out of service at 15!

Short answer: for DOT Carbon Fiber Wrapped Cylinders Hydro Test Every 5 years and service life is 15 years!

The Dive shop is certainly in error about the service life!

Thurmond,

SCUBA tanks need to be Hydro'd every 3 years and this is what dive shops normally deal with. They are in error about the CF being every 3yrs as opposed to every 5 years, but they would be correct on the life service. Remember he is not starting with a new tank, it's 6 years old. So add to that the 9 yrs (3 Hydro's at 3 yrs each) they are telling him and you get the 15yrs.

Well then as Emily Litella used to say long long ago: "Never Mind"!

 

[Centercut]

Hydros for CFFC tanks are 5 years. 15 year service life. Look at the DOT regs. It’s been covered with references on AGN many times in the past couple of years. 20 years ago it was 3 years but that’s been changed for a long time. ..

These are the manufacturers government requirement:

https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/docs/technical-resources/55751/basic-requirements-fully-wrapped-carbon-fiber-reinforced-aluminum-lined-cylinders.pdf

Periodic test Requirements from DOT-E-11194

E-11194 Carbon filament "CFFC" cylinders: 

Manufactured or tested after July 1, 2001 must be reinspected and hydrostatically retested at least once every 5 years. If the retest was done prior to July 1st, the next retest must be done within 36 months. All subsequent retests must then be done every 5 years. 

Have a maximum service life of 15 years from the month of manufacture. DOT may, in the future, extend the service life of these cylinders. 

Are tested at 5/3 times the marked service pressure and held at test pressure for a minimum of 60 seconds. 

Are rejected if the rejection elastic expansion "REE" that is marked on the label is exceeded. 

May only be retested two times (EQUIPMENT FAILURE CAUSE ONLY) at a maximum of 200 psi over the original test pressure, to avoid damage. 

Must have the test date marked by the label and epoxy covered.