PST Steel 72 3000 PSI?

[Bearded Diver]

The steel 72 is actually about 71 cuft when it is filled at 2475 psi. That is the cylinder stamped with 2250 (psi) filled with the extra 10%.

On average, the steel 72 has:

an outside diameter of around 6.9 inches

it is around 25 inches tall

the average wall thickness is about 0.176 inches

with a valve and boot it weights around 30 pounds (empty), 35 to 36 pounds full.


The 3000 psi stamped cylinder was actually called a steel 95 (that is what I have heard), but they are actually around 93 cuft when they are filled to 3300 psi. That is including the 10% overfill with the plus(+) stamp.

This steel tank has:

An outside diameter of around 7.0 inches

it is around 25.25 inches tall

the average wall thickness is about 0.23 inches

with a valve and boot it weights around 40 pounds (empty), around 47 pounds full.

When empty, these cylinder is about 7 to 8 pounds heavier in the water than a steel 72. I measured the displacement of my two cylinders.



So they may look similar, but they are two totally different cylinders. The wall thickness alone is 30% thicker.

I have two of those cylinders. But I haven’t dived them yet. They are very heavy.

It is a great cylinder if you need that much air and you can handle that much extra in the water weight. That would remove about 8 pounds of lead from my weight harness, which would be great. But here in Maine I very rarely need that much air. I would get cold and bored long before I consume that much air. Most of our dives are shallow.

Is there a way to find out the CF of a PST tank with 3500 psi rating? Looking at two tanks with that rating and I don’t see any standout stamps regarding CF

 

[tursiops]

Is there a way to find out the CF of a PST tank with 3500 psi rating? Looking at two tanks with that rating and I don’t see any standout stamps regarding CF

I'll bet they are 100 cuft. What do they weigh, and what are the diameter and height?

 

[rx7diver]

Is there a way to find out the CF of a PST tank with 3500 psi rating? Looking at two tanks with that rating and I don’t see any standout stamps regarding CF

Does this cylinder have an O.D. similar to an Al80's (~7.25")? If so, then this PST cylinder is probably 82 cu ft if it has an height of ~20", 102 cu ft if ~24", and 122 cu ft if ~28".

ETA: See, for example, SCUBA Cylinder Specifications – Huron Scuba, Snorkel & Adventure Travel Inc. PADI 5 star IDC in Ann Arbor, MI.

rx7diver

 

[Bearded Diver]

Does this cylinder have an O.D. similar to an Al80's (~7.25")? If so, then this PST cylinder is probably 82 cu ft if it has an height of ~20", 102 cu ft if ~24", and 122 cu ft if ~28".

ETA: See, for example, SCUBA Cylinder Specifications – Huron Scuba, Snorkel & Adventure Travel Inc. PADI 5 star IDC in Ann Arbor, MI.

rx7diver

I do know that the rocking pressure is 3500. I can post some images that might help.

 

[Bearded Diver]

Does this cylinder have an O.D. similar to an Al80's (~7.25")? If so, then this PST cylinder is probably 82 cu ft if it has an height of ~20", 102 cu ft if ~24", and 122 cu ft if ~28".

ETA: See, for example, SCUBA Cylinder Specifications – Huron Scuba, Snorkel & Adventure Travel Inc. PADI 5 star IDC in Ann Arbor, MI.

rx7diver

These are from the seller that lives many hours away from me. She is not too familiar with tanks. She wasn’t even sure what some of the markings meant. Hoping this makes an ID easier. Thank you in advance

 

[Bearded Diver]

I'll bet they are 100 cuft. What do they weigh, and what are the diameter and height?

I’ll need to reach out to the seller to see if she can weigh/measure them. These are my first PSTs so getting familiar with markings

 

[rx7diver]

These are from the seller that lives many hours away from me. She is not too familiar with tanks. She wasn’t even sure what some of the markings meant. Hoping this makes an ID easier. Thank you in advance

Your pics are consistent with the PST 3,500 psig cylinders I refer to in my post. If you know the approximate height, measured from the floor to the top (without boot and without valve), that will tell you which particular one you have.

Oh, and there is a fourth cylinder, too: a HP65 that holds ~67 cu ft and is ~17 inches tall (same 7.25" diameter). It, too, is described on the Huron Scuba cylinder specifications page. Unless you are very short, you almost certainly do NOT want this one.

And unless you're reasonably tall, or have a long torso, you almost certainly do NOT want the HP120. I am 6'2", with long legs, and my PST HP120's (122 cu ft @ 3,500 psig) are taller than I prefer for wearing as singles. Other divers who are my height, but who have shorter legs and a longer torso, like the HP120 just fine.

Per the Huron Scuba specs, these cylinders are negatively buoyant--so much so that I will NOT wear my HP120 in fresh water when I am wearing my thin wetsuit. My HP80 is almost too negatively buoyant for me to wear in fresh water when I am wearing my thin wetsuit.

ETA: Also, some divers find the HP80 a bit too short.

rx7diver

 

[Bearded Diver]

Your pics are consistent with the PST 3,500 psig cylinders I refer to in my post. If you know the approximate height, measured from the floor to the top (without boot and without valve), that will tell you which particular one you have.

Oh, and there is a fourth cylinder, too: a HP65 that holds ~67 cu ft and is ~17 inches tall (same 7.25" diameter). It, too, is described on the Huron Scuba cylinder specifications page. Unless you are very short, you almost certainly do NOT want this one.

And unless you're reasonably tall, or have a long torso, you almost certainly do NOT want the HP120. I am 6'2", with long legs, and my PST HP120's (122 cu ft @ 3,500 psig) are taller than I prefer for wearing as singles. Other divers who are my height, but who have shorter legs and a longer torso, like the HP120 just fine.

Per the Huron Scuba specs, these cylinders are negatively buoyant--so much so that I will NOT wear my HP120 in fresh water when I am wearing my thin wetsuit. My HP80 is almost too negatively buoyant for me to wear in fresh water when I am wearing my thin wetsuit.

ETA: Also, some divers find the HP80 a bit too short.

rx7diver

Thanks for the information. I currently own 3 133s and a 149. Don’t use that often, but with lobster season coming around and mini season tomorrows they will get some use. I will have to ask the seller the measure the tank height and I also read the circumference will make the cf identifiable in regards to pst tanks