HP or LP double

[Spratman]

As was mentioned above, LP's are great when you are getting those babies pumped at the LDS. However, anywhere else you go except maybe cave country, will only fill them to the rated pressure. I've got the LP95's because of an exceptional deal on them. But maybe two sets would be better....one HP, one LP. Then you are covered. But for the first set and if you have the money, do for the HP100's.

 

[PerroneFord]

Spratman,

Here's the problem.

Lets say I buy a LP95 and you buy a HP100. We are in say Boston. They will fill both of our tanks to rated pressure. I get 95cuft, you get 100.

We go to NYC, they have a 3000psi compressor. They are willing to overfill my tank. Now I get 107cuft and you get 85.7.

Now we come to N.FL. to dive the springs. They have a 3500psi compressor. They give us both 3500. I get 126cuft, you get 101.

The only instance in which you get more gas than me is if we are at a shop with a compressor that can push 3500psi AND they are not willing to overfill me. In that instance, I get exactly what I paid for.

 

[Scubakevdm]

Scubakevdm,

How are the 121's to dive and walk with. I am buying tanks this winter and am considering those and 108s.

I'm 6'1", and weigh right around 240. I don't have alot of trouble walking around in them, but standing can be tricky, though that may be at least in part due to the configuration of the tank racks on our boat. They bind the rig and you have to kinda pop it free. Diving them gives me the sensation of having a table on my back. My head and butt both make contact with them, but not badly. I have a set of 104s as well, they're alot easier to deal with, but the extra gas is sometimes nice for certain non-mainstream situations.

 

[PerroneFord]

You're an inch taller than me, and about the same weight. Good to know. My walk is quite a bit longer than yours though!

 

[CompuDude]

The HP130 is a LP104 equiv... the HP119 is the LP95 equiv.

I read recently that Worthington is no longer making LP tanks for that very reason. You're just supposed to buy the HP tanks and fill them less, since the external sizes are the same. Dunno if that info was correct, but it sure makes sense.

 

[lamont]

The one other thing is that LP tanks are DOT-3AA, while all the HPs are covered under one of the exemption numbers (e.g. E-9791 for PST). All the drama over the E-series PST tanks is all moot for the LP tanks...

I'm hoping that all the recent posts that the DOT will not do personal exemptions is just FUD from PST-haters, but if not, then there's a benefit for you of the LP tanks (although Worthington will probably not go out of business or fail to renew their exemption...).

 

[XS Scuba]

Hi CompuDude:
The information you read is not correct. We currently have Worthington manufacture 13 sizes of steel cylinders for us (Sea Pearls is the same). Four sizes are DOT3AA 2400+ psi, four sizes are DOT3AA 3130+ psi and five sizes are DOT E14157 3442 psi. The specifications can be viewed here: http://xsscuba.com/tank_steel.html We have no plans of discontinuing production of any of these cylinders. In fact, we plan to introduce two new sizes at the DEMA show in November. One is a 3AA 2400+ psi cylinder and the other is another X-Series cylinder 3442 DOT E14157.
Also, if you are of the belief that the DOT 2400+ psi cylinders are just "down rated" high pressure cylinders, you are wrong. Our low pressure steel cylinders are manufactured to meet all the requirement of the DOT 3AA classification for 2400+ psi, no more. They are not "overbuilt" in anyway to exceed the requirements of DOT. They are no more safe or no more unsafe to pressurize beyond 2640 psi (2400+ psi) then any other 3AA 2400+ psi scuba cylinder. I suggest if you plan to fill your cylinder beyond 2640 psi, then purchase an X-Series cylinder which is designed for fills to 3442 psi.

I read recently that Worthington is no longer making LP tanks for that very reason. You're just supposed to buy the HP tanks and fill them less, since the external sizes are the same. Dunno if that info was correct, but it sure makes sense.

 

[PerroneFord]

Would you characterize your cylinders as As safe, less safe, or more safe, than the Faber 3AA steel tanks that we have been overpressurizing for nearly 30 years? Are they equally as safe as the PST cylinders that people have been putting 3500-4000psi In since the 80s?

Since I intend to purchase some new LP cylinders this winter, I want to be sure that if I purcahse Worthington tanks, I am not getting an inferior product when I could purchase PSTs or Fabers.

Thank you.

-P

Also, if you are of the belief that the DOT 2400+ psi cylinders are just "down rated" high pressure cylinders, you are wrong. Our low pressure steel cylinders are manufactured to meet all the requirement of the DOT 3AA classification for 2400+ psi, no more. They are not "overbuilt" in anyway to exceed the requirements of DOT. They are no more safe or no more unsafe to pressurize beyond 2640 psi (2400+ psi) then any other 3AA 2400+ psi scuba cylinder. I suggest if you plan to fill your cylinder beyond 2640 psi, then purchase an X-Series cylinder which is designed for fills to 3442 psi.

 

[BigTuna]

My LDS overfills my new LP85s by about 20% (they are rated at 2400 + 10%). I count on this for my dives. But I wonder if the shop will continue to overfill after the tanks' hydro in 5 years.

The reason I wonder is I've been told that LP tanks routinely lose their +10% rating at their first hydro, presumably because it's too hard to check to make sure the tanks haven't cracked or something. So how willing will a shop be to overfill a tank that no longer has its +10% rating? If they are unwilling, it would mean that the practical life (for me) of an LP tank is 5 years.

Can anybody confirm and expand on this? Maybe the possibility of this kind of 5 year life limit should be a factor in a decision to buy LP vs. HP.

 

[PerroneFord]

Getting tanks to pass the "+" rating isn't difficult at all. We have LP tanks at the shop from the 80s that still get 3500psi.