Worthington LP7-77

[Rainer]

Actually you can only "overfill" to the plus rating if it has the plus on it after hydro. At the second hydro, it might not pass the plus rating and only be rated for 2400psi (instead of 2640psi).

It *could* lose the plus rating, but it's not that likely...

Some folks however pump up LP tanks to 3000psi or 3500psi, or even higher such as 4000psi. Pretty common in cave country. Now that's overfilling.

Yeah, and so what? If the tank has the + rating, then filling to that pressure leaves the tank as a 77cf. That's not over-filling.

 

[mike_s]

It *could* lose the plus rating, but it's not that likely...



Yeah, and so what? If the tank has the + rating, then filling to that pressure leaves the tank as a 77cf. That's not over-filling.

my point was that people often fill tanks past 2640psi up to 3000-4000psi. that's overfilling. (of course you get more than 77cf that way, but that's the point of overfilling).

 

[SparticleBrane]

Most shops will fill for the + even if it doesn't have it.

 

[XS Scuba]

Hey Mike:
The Nominal Internal Volume of the LP77 is 737 cubic inches. That is, if you filled it full of water that is the what it would hold. If you were to measure the Internal Volume of an old Steel 72, you will find it holds less water. So the Steel 72 will always hold less gas then the LP 77 if the two cylinders are filled to equal pressures. Remember, the Steel 72 holds 71.2 cubic feet at 2475 psi (2250 + 10%). The Steel 72 is a 6.9" diameter cylinder and the LP77 is 7.25". The majority of Steel 72's were manufactured by PST. It has been many years since this cylinder was manufactured. The LP77 when compared to the Steel 72 is a better designed cylinder for the average diver.

since you're asking comparison against the old 72's...

if you only fill the LP-77 to 2400psi, you only get 70cf. (some shops won't overfill).

So what's the advantage of this tank over an old steel 72? (besides it just being newer ?)

 

[mike_s]

Hey Mike:
The Nominal Internal Volume of the LP77 is 737 cubic inches. That is, if you filled it full of water that is the what it would hold. If you were to measure the Internal Volume of an old Steel 72, you will find it holds less water. So the Steel 72 will alway hold less gas then the LP 77 if the two cylinders are filled to equal pressures. Remember, the Steel 72 holds 71.2 cubic feet at 2475 psi (2250 + 10%). The Steel 72 is a 6.9" diameter cylinder and the LP77 is 7.25". The majority of Steel 72's were manufactured by PST. It has been many years since this cylinder was manufactured. The LP77 when compared to the Steel 72 is a better designed cylinder for the average diver.

ahhh... good point you make. The 72 was 2250psi +10% (2475 total) to get the 72 (or 71.2cf).

So seeing how many/most 72's I'm betting aren't plus(+) hydro'd anymore, no comparision. It should be a volume difference from 2475psi @ 71.2cf down to 2250psi and a volume of 64cf.

big difference in 64cf an old steel 72 (w/o + rating) and 77cf of your new tank.

 

[Cheekymonkey]

Itsw all kind of a moot point if no one can find someplace to buy them.

 

[Adobo]

Itsw all kind of a moot point if no one can find someplace to buy them.

Well.. not no one. I have a set doubled up. I've only dived them once. From what I could tell, their trim characteristics were not significantly different than my X7-100 doubles.

 

[mike_s]

Itsw all kind of a moot point if no one can find someplace to buy them.

Looks like Phil took care of that problem.

He's got the LP-77 for sale for $189 including free shipping in the Hot Deals section.
http://www.scubaboard.com/showthread.php?t=180375


Considering an AL80 costs $150 to $170 now, if you buy a LP-77 with the free shipping, it'll run you about the same cost as a AL80 that you have to pay shipping on.

Sounds like a Deal.

 

[Cheekymonkey]

Looks like Phil took care of that problem.

He's got the LP-77 for sale for $189 including free shipping in the Hot Deals section.
http://www.scubaboard.com/showthread.php?t=180375


Considering an AL80 costs $150 to $170 now, if you buy a LP-77 with the free shipping, it'll run you about the same cost as a AL80 that you have to pay shipping on.

Sounds like a Deal.

'


awesome ty