New "E" series PST tanks

[lucid]

So will the tank fill up at 3440 or a lower pressure? Sorry I'm tank retarded.

/quote

Its my understanding that they will fill out at 104 at 2640 but will be rated and stamped at 3400 so that you can 'legally' fill them to 3400 psi and yield 133ft^3 of gas. Am I way off?

/quote

 

[pescador775]

That's double talk. When the DOT approves a rating, that's what it is.

Board chatter has it that the new tank will be 100 cu ft at 3440. It may be that PST is still mulling over the final lineup.

 

[Genesis]

The one that the "cavies" are probably interested in looks an awful lot like an LP104 at 2640, but ends up at ~133 cubes at 3400ish - they're calling that their "130" tank..

The HP100/120 line is being redesignated, and apparently the tank threads are going to the standard 3/4" across the board.

PSI told me that some of the new line would be available end of January, with others showing up between then and the end of March.

I have two on order at a shop in PC as soon as they can actually get me a delivery date.

 

[Scuba]

lucid once bubbled...

Its my understanding that they will fill out at 104 at 2640 but will be rated and stamped at 3400 so that you can 'legally' fill them to 3400 psi and yield 133ft^3 of gas. Am I way off?

All tanks are rated at their maximum allowable fill pressure, (ei. 80 cf @ 3000 psi.) with the exception of some steel tanks incorporating a + sign. The + sign allows 10 % overfill beyond the rated pressure.

PST steel 104 + is rated 2400 psi, hence you can legally overfill 10% which comes out to 2640 psi. In addition, in order for this tank to contain 104 cf of gas you must fill it to 2640 psi.

Any tank can be filled to less than its rated pressure, this will give you less gas in cubic feet.

 

[pdoege]

Whilst hanging out looking for spring straps, I stumbled across some specs for the E series at Lloyd Bailey's site.

http://www.lloydbaileysscuba.com/PST E Series Tanks.htm

Peter Doege

 

[pescador775]

Thanks, Peter, great link. I expect that the resale price of used LP 104's may rise in Minnesota and points north. As expected, the new E series 130, is three pounds less negative than the comparable LP 104.. Means six pounds more ballast for a set of double 130's. Overall, the new lineup looks promising.

 

[pescador775]

There may be some extreme rounding off of numbers on that table. Depending on how the numbers game is played, it looks like the 130 is closer to Genesis' number of 133 cf at 3442 psi rather than the furnished number of 130.

 

[SPEEDSTER]

I just rec'd a table from someone on quest supposedly from pst. the empty weights don't jive with Lloyd Bailey's. Here's the info just on the E8-130, I hope it posts ok.


NUMBER E8-130
(DOT) E9791
PRESSURE 3442 PSI
CAP.(ci) 1013
CAP.(lt) 16.60
@ 3442 PSI 130.0
@ 3000 PSI 119.1
@ 2640 PSI 106.1
INCHES 8.0
INCHES 25.56
LBS. 42.2
EMPTY -4.8
FULL -12.6
THD 3/4-14 NPSM

 

[pescador775]

If I were a PST engineer, I would be trying to duplicate the buoyancy of the old LP 104. This seems to be what divers want. However, the high tech alloy E9791 is much tougher than 3AA of which the LP tank is made. The HP tank requires thinner sidewall for the same or higher pressure rating. If the HP tank is indeed the same neg buoyancy where is the extra 3 pounds of steel going, in the sidewalls? The HP and LP have the same internal volume. The LP weighs about 46 pounds and the HP weighs about 42 pounds, dry. So, I don't see how the E130, at 4 pounds less dry weight than the LP104, can be 4.8 pounds negative, or identical to the heavier LP tank. There is no extra steel in the HP tank to produce this much negative buoyancy.

 

[ScubaDan]

pescador775 once bubbled...
If I were a PST engineer, I would be trying to duplicate the buoyancy of the old LP 104. This seems to be what divers want. However, the high tech alloy E9791 is much tougher than 3AA of which the LP tank is made. The HP tank requires thinner sidewall for the same or higher pressure rating. If the HP tank is indeed the same neg buoyancy where is the extra 3 pounds of steel going, in the sidewalls? The HP and LP have the same internal volume. The LP weighs about 46 pounds and the HP weighs about 42 pounds, dry. So, I don't see how the E130, at 4 pounds less dry weight than the LP104, can be 4.8 pounds negative, or identical to the heavier LP tank. There is no extra steel in the HP tank to produce this much negative buoyancy.

If you look at there existing HP tanks they are only 7.3 inch in diameter. And the new HP tanks are 8.0 inch perhaps that's were the extra weight is.