Karloss
Contributor
I'm curious are steel 95 cf tanks neutral or positive at 500 PSI ? Thanks.
Steel 95's
- Thread starter Karloss
- Start date
Please register or login
Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
- Ability to post and comment on topics and discussions.
- A Free photo gallery to share your dive photos with the world.
- You can make this box go away
A steel 95 is almost always going to be negative
amnstoner
Contributor
Here you go... Most of everything you would want to know about a variety of tanks is listed on this sheet. If you need any help with it. PM me.
Austin
They vary a bit by brand.
A Faber steel LP 95 is going to be about 2 lbs negative with 500 psi.
A PST or a Worthington steel LP 95 is going to be about 4 lbs negative with 500 psi.
A Faber steel LP 95 is going to be about 2 lbs negative with 500 psi.
A PST or a Worthington steel LP 95 is going to be about 4 lbs negative with 500 psi.
freedc
Contributor
Austin,
This is a very cool spreadsheet. Since i'm a relative newbie I'll ask the dumb question: which spec tells me how much total air the tank can/will hold? Is it capacity in cubic feet?
I'm used to diving with AL80's and we always measure how much air we have left by PSI. Does a diver with an AL80 and 1000 PSI reading on his SPG have less air time remaining than a physiologically identical diver with 1000 PSI and a steel 100?
Sorry to hijack.
walke121
Contributor
Capacity in CF tells you how much air the tank holds at its rated pressure. If the capacity is in liters then that is the "size" of the tank. Since water can not be compressed. An HP 119 roughly is the same size as a LP 95 and HP 130 to a LP 104. Yes the diver with the AL 80 has less time than the diver with the steel 100. You can figure out what the ratio of psi is to CF very easily.
As for the OP's question I can't recall any steel tank I've seen being pos.
Diveral
Contributor
walke121
Contributor
Assuming the AL80 is rated at 3000psi you have 26.667 CF left at 1000 psi. Assuming the steel tank is HP you have 29.05 CF left if the steel tank is LP you have 41.67 CF left which is a huge difference.
3AA steel tanks (low pressure tanks, mid pressuire tanks in the 3000-3180 psi range, and basically anything with a a "+" on it) have a "rated" capacity based on a 10% overfill.
Special permit steel tanks and aluminum tanks use the a rated capacity based on the service pressure.
The spread sheet is impressive but some of the numbers are a pound or two off as some sites and sources base tank weight on the weight with valve and others list the weight of the tank without the valve.
Special permit steel tanks and aluminum tanks use the a rated capacity based on the service pressure.
The spread sheet is impressive but some of the numbers are a pound or two off as some sites and sources base tank weight on the weight with valve and others list the weight of the tank without the valve.
soamelt
Contributor
That's a great reference guide! I think the Worthington X7/8 series have their weights reversed for empty/full, although I'm sure most would easily figure that out when comparing the two.
Similar threads
