LP tanks

[oldguy]

I have read so much debate about tanks on the net that I just fill my 104's to 10,000 psi, turn at 6,600, and do my deco with the left over 3,300 during an OW dive the next week !!!! So much for my cavern training.......

[lonestarfl]

I use Faber tanks. They are lighter than the Pressed Steel and easier for me to carry out of the water.

Are there any Faber type (weight) tanks that have the rated fill pressures of the new E series tanks?

Richard

Richard,
It is interesting to note that when Faber tanks were originally imported to the USA by Cressi-Sub over 15 years ago they had no DOT stamp and and a rated fill pressure of 200b or 3000psi without a 10% overfill. When Scubapro began importing the tanks they had a DOT stamp and were derated to 2640psi with the 10% overfill....same tank just derated to fit existing regulation and a change in color from yeloow to white. When OMS put their name on the Faber tanks the color changed from white to grey but not the fill ratings.
The Faber tanks are still sold in Europe today with a 200b rating and typically filled to 232b...a little over the 10% overfill.
So, the Faber tanks are engineered to withstand 3000ps1-3500psi fills as routine duty. It is only manufacturers jumping through goverment regulatory hoops that have them derated, not safety issues.
Kind of like the need for burst disc in valves...but that is a whole different can of worms!!!
Lee

I have heard so many different versions of this tale that it is hard to know what to believe these days. Seems like most folks say that the cylinders we have here and those in Europe are exactly the same, while others state that there is a difference between the two and thus the US cylinders are not capable of being repeatedly filled to the much higher pressures; different alloys and different specs such as wall thickness seem to be the most offered variances that I have heard. I have been filling my Fabers to typical "cave fill" pressures and have yet to notice any problems with them, but it would be nice to be able to read some "official" report to know which version of the marketing story is true. Do you know of such a source Lee?

My source is that in 1985 I used a pair of Cressi-Sub yellow 108's. These were Faber tanks and did not have a DOT stamp. They were purchased in Miami by a fellow cave diver and light builder, Bob Duncan, and some of the first Fabers in the US. They were stamped 15 L and 200b....we filled them to +10%, 3200psi. A few years Later Scubapro imported these cylinders in white with DOT stamp. To comply with current DOT specs/approval they had a rated fill pressure of 2400psi which gave 95cuft at 2640. These tanks were then imported by OMS in grey.
I dive in both the US and Europe. I can promise you that the Faber tanks are the same steel on both sides of the Atlantic. The size, weight, and bouyancy are identical. The differences are color and stampings except that tanks with valves in Europe have no burst disc. In Europe the tanks are marked in liter capacity, and bar fill pressure with a CE approval.
In the US the tanks are marked in cuft, psi fill pressure and DOT approval.
In Europe there are heavier tanks that are rated to 300b by Beauchat and Heiser. But there are only a few first stages rated to handle 300b and limited dive shops that bank +300b for filling.
In addition to these European tanks there are the HP steel tanks from Japan by Asahi which are rated at 3500psi and have the 5/8" tank thread.
The new PSI steel tanks rated at 232b are a new DOT class/approval. I don't know if the alloy has changed, but I can tell you that the weight, size and bouyancy of this new E-series has changed minimally. They may have just retested and uprated the old tank design at a highter working pressure.
I have yet to have much exposure to the Worthington steel tanks.
I am giving you the facts as I know them from my experience. If you have further questions let me know.
Lee

[Puttzer]

OK, now that I'm really confused I decided to contact Faber directly. Here is what they told me by email:

"When we receive an enquiry like yours one regarding our cylinders, in order to be precise we need to have the serial number of the cylinder(s) the sender is referring to.
Generally speaking the threads of the cylinders we sell in Europe are normally requested to be M25x2 DIN 477 or a M25x2 EN 144-1 while normally the thread of the scuba diving cylinders we have been selling and we are selling in the US market is requested to be a 3/4"-14-NPSM CGA V1.
Concerning the manufacturing standards, the cylinders we sell in the US market must comply with the DOT 3AA standard.
In Europe there are different European standards and also national standards that may vary country by country even though since June 2002 the scuba diving cylinder sold inside the European Union must comply with the European Directive 97/23/EC Pressure Equipment Directive. However the standard DOT 3AA is not among the ones used and/or allowed in the different European countries.
A comparison among the different manufacturing standard is in any case practically impossible."

So I guess the next question is: how does the standard DOT 3AA compare to the European Directive 97/23/EC Pressure Equipment Directive?

[Puttzer]

Ok, I give up.

Below is the second reply I got directly from Faber. FWIW, they are nice to take the time to reply and I appreciate that. Some of you may be able to better "word" your questions. Just wish I could ask more directional questions that could get more direct answers. (I didn't think asking them if I can overfill my US tanks, would get a candid answer.) But here 's their last response.

"As I wrote you in my mail of today the cylinders we sell in the US market are manufactured according to the DOT 3AA standard (recently we got also a DOT exemption so we sell also DOT exemption cylinders).
The cylinders we sell in Europe are not manufactured according to DOT 3AA or DOT exemption standard.
"