Do You guys think this would be a good first scba tank for 3000psi guns?
after its unable to be recertified is it still safe too use?will you be able to tell when the tank is failing before it goes boom ?
okay hmmm decisions decisions it says in the description that they were hydro and will be good for another five years so it will be okay for five years. maybe I should call and talk to him directly...
(CFRP) SCBA cylinder maintenance requirements were established in the early 1990s based on cylinder manufacturer input. At thattime, there was extensive experience with aluminum-alloy tanks but very little knowledge of the long-term durability and strength characteristics of fiberglass or carbon fiber. A lower limit on the service life of composite-wrapped cylinders was established at 15 years based on limited studies on the durability of fiberglass observed in testing for NASA aerospace applications. The 15-year cylinder life is also linked to cylinder cycle testing (fill-and-empty cycles) at the time of manufacture, when two percent (2%) of all cylinders manufactured are cycled 10,000 times (corresponding to about one cycle per working day for 40 years), then subjected to a number of strength tests. Cylinder manufacturers submitted that this testing established a threshold level of acceptable safety that can be reasonably expected over a 15-year service life (regardless of the working gas).
15 year life was determined in 1990 based on non carbon fiber tanks and 10,000 cycle life at which point 222% wouuld fail during Hydro testing which is 5/3 of rated max. working pressure.The metal becomes fatigued and work hardened due to expansion and contraction. When Hydro test is done they check for the amount the tank expands and if it does not expand enough then it fails. Most air gunners tanks do not get discharged to near zero like fire fighters and other who use them for a breathable air source. Most of our tanks do not get filled an average of 5 times a week which is where the 15 years came from with a rather large safety margin.Quote(CFRP) SCBA cylinder maintenance requirements were established in the early 1990s based on cylinder manufacturer input. At thattime, there was extensive experience with aluminum-alloy tanks but very little knowledge of the long-term durability and strength characteristics of fiberglass or carbon fiber. A lower limit on the service life of composite-wrapped cylinders was established at 15 years based on limited studies on the durability of fiberglass observed in testing for NASA aerospace applications. The 15-year cylinder life is also linked to cylinder cycle testing (fill-and-empty cycles) at the time of manufacture, when two percent (2%) of all cylinders manufactured are cycled 10,000 times (corresponding to about one cycle per working day for 40 years), then subjected to a number of strength tests. Cylinder manufacturers submitted that this testing established a threshold level of acceptable safety that can be reasonably expected over a 15-year service life (regardless of the working gas). 2% failure after 10,000 cycles which is 260 per year for 40 years. 260 per year (one per week) for 15 years is 3,900 fills or right at 40% of full 0 to max. pressure cycles for 2% failure rate to be reached.
His ad used to say "1 to 2 years left", if you call I think he will tell you that the DOM is either 2000 or 2001. Which means they "expire" (according to DOT regulations) in 2015 or 2016, no matter what the Hydro is.
These are 4500 psi 45 min. SCBA carbon fiber tanks. They hold 66 cubic feet. The valves have been gone through and resealed and the tanks are under a new hydro test in Jan/2015, or 4/2015. These tanks are intended to get new-comers, on a budget, into the sport.
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