High Pressure Steel

[Mo2vation]

I am in the market for a high pressure (3442 PSI) steel cyclinder, I'm thinking 120 cubic foot or 119 cubic foot tank size... <snip>

Why wouldn't you buy a 130? I mean, if you're condidering getting a 119, why not step up to the 130. More gas, not appreciably more weight or cash. Just more gas.

I can see if you're going back and forth between the 100 and the 130... If you're thinking about the 119, get the waterheater. Get the 130.

---
Ken


PS: the 130 has much, MUCH better resale value, too.

 

[Al Mialkovsky]

They did that 3442 so they could stick a yoke on it as though it really doesn't need a din valve.

I have PST's and Worthingtons. As far as I'm concerned I can't tell the difference when I'm diving.

 

[stiebs]

Dr. Bill is correct the 3442 psi exactly = 230 bar, and that's not 3500 psi. And of course the steel tanks are never rated "+". The PST valve comes with an insert so you can use it with a yoke type regulator that is rated to 230 bar.

Actually 3442 PSI is exactly 237.317546 bar.
232 bar (the standard rating in Aus) is 3364 PSI.

 

[Hoosier]

Just trying to be accurate on this for those who read these posts. There is a reason the "new" 3,442 psi tanks are not listed as 3,500 psi. If I'm wrong, please feel free to correct me and ensure we ARE accurate in the information we present.

Gee..... No harsh..~~
I don't know why you took my post in that way. :06: Even, I didn't quote your previous posts. I just tried to give the comprehensive list for the spec, specially about a weight and length...

Sure, there is a reason not to be rated 3,500 psi....

 

[spectrum]

I like my PST-120. One consideration, though, is that it seems difficult for some dive shops to deliver a full fill. You will virtually never get a full fill on a dive boat. That said, the 120 still holds 107 cu ft. of air at 3000 psi, quite a bit better than the AL-80. Dr. Bill is correct the 3442 psi exactly = 230 bar, and that's not 3500 psi. And of course the steel tanks are never rated "+". The PST valve comes with an insert so you can use it with a yoke type regulator that is rated to 230 bar.

Then again I don't see too many of my buddies showing up at the site site with perfect fills on AL80s either. Granted a nice fill is easier on a LP steel since there's less energy involved. My experience has been that shops are more willing to overshoot a little on a steel cylinder for a perfect cool pressure.

Now if the shop just can't pump past 3000 that's another story.

As I think you're saying even with a short fill the "HP" steels have a nice capacity to weight ratio and great buoyancy properties.

Pete

 

[LLKZ16]

Why wouldn't you buy a 130? I mean, if you're condidering getting a 119, why not step up to the 130. More gas, not appreciably more weight or cash. Just more gas.

I can see if you're going back and forth between the 100 and the 130... If you're thinking about the 119, get the waterheater. Get the 130.

---
Ken


PS: the 130 has much, MUCH better resale value, too.

EXACTLY!!

I COULD NOT HAVE SAID IT ANY BETTER!

 

[Dive1Dennis]

Thank you all for the feedback about these tanks. This is just what I was hoping for.

Why wouldn't you buy a 130? I mean, if you're condidering getting a 119, why not step up to the 130. More gas, not appreciably more weight or cash. Just more gas.

I can see if you're going back and forth between the 100 and the 130... If you're thinking about the 119, get the waterheater. Get the 130.

The waterheater? I like that.
I hadn't thought about going up to the 130, but you have got me thinking. I think I like the 120 because I dove one last year and found it compact, like the AL80s I have now but it had copious amounts of air and I dropped 5lb off my weight belt. This tank would allow me to easily switch back and forth between the 120 and the AL80 for dives where I don't need the big tank.

Technically I believe a true HP (high pressure) tank is rated at 3,500 psi or higher. The 3,442's are rated at that level because it places them just under the high pressure designation.

Thanks for the clarification Bill. In my original post I was careful to list the actual pressure ratings because I know that 'high pressure' means different things to different people, especially our European friends. I too understood the 3442 PSI rating as a level that allows use of yoke or DIN valves.

Here is the comprehensive spec. sheet.....

Thanks Hoosier - saves me the trouble of putting the details side by side.

after doing a few VIPs on new worthingtons and PSTs I found the fit and finish is a bit better on the pst. The galvanize dip isn't quite as nice on the worthingtons.

A number of comments about the better finish on the PSTs, but it doesn't sound like a show stopper.

I also had/have some concerns about the health of PST. I have read other posts, including a current one that seems to have this covered, and indicate that the DOT exemption should not be a problem, even if PST should fold, but ??? Does Worthington have this same type of exemption?

Thanks again for all the feedback.

 

[JS1scuba]

I am in the market for a high pressure (3442 PSI) steel cyclinder, I'm thinking 120 cubic foot or 119 cubic foot tank size. I was set to buy a PST after I dove with a borrowed one last year. The 120 is a great cyclinder, not much bigger than an AL80 with negetive bouyancy.

Now I learned that Worthington has gotten into the high pressure steel scuba cyclinder market. They are sold through Sea Pearls. Their steel tank spec's are nearly identical to PSTs.

Does anyone have any experience with the Worthington cyclinders? Any feedback about them? A real bonus would be a comparison between PST and Worthington.

Thanks,

Hi Dennis,

The Worthington tanks are excellent. They were made to a very nice specification and have all the features you want. The finish is not as "sparkly" as some of the PST tanks are but note that all galvanized cylinders after exposed look "grey" on the outside. The TWX-119 is the physical size of an LP 95 but holds the gas of 119 cuft at 3442 psi. What is nice about this size tank as i call it "variable volume" at 2600 psi it has 95 cuft .......

You can compare them on our tank cylinder chart to ALL the currently made cylinders. We stock Worthington and Faber steel cylinders and ship them on a daily basis.

http://www.techdivinglimited.com/pub/tanks.html

Cheers

 

[NAVY21]

I keep having a problem with some dive shops short chaning me on my HP 120...which is a pain in the butt b/c I use it to get 2 dives in when everyone else is doing 2 80s-which gets hard when lds gives me 3000psi instead of 3442...but something this dive shop on cape cod does is they put ur tank (minus the valve) into a tub of chilled water during the fill and bam...perfect fills every time.

 

[lamont]

A number of comments about the better finish on the PSTs, but it doesn't sound like a show stopper.

I think what people are actually saying is that the PSTs look shinier when new. I've never actually heard someone argue that the finish is in some way better corrosion-resistance or anything like that...

If you get an LP worthingon instead of the HP X-series, then you'll probably (unless they've already converted the LP series to all hot-dipped?) get the white coating which can chip and rust if you bang it around. I like the hot dipped better, but plenty of divers love their faber tanks that have the white coating...

AFAIK, the worthington and PST hot-dipped finish is identical in every respect that actually matters, although the PST coating does have more of a track record...