Where to get the "+" renewed on steel tanks

[kelpdiverguy]

I'm just curious and wanted to see if anyone already knew...

Has anyone been successful in having an LP steel tank hydro'd and the "+" status renewed anywhere in the Monterey area? If so, what shop or service did this for you?

I'm looking to get the full capacity out of LP steel, but I understand that the "+" is often ignored during hydro, even if the customer requests it. Any info is a help, thanks.

 

[adelman]

Has anyone been successful in having an LP steel tank hydro'd and the "+" status renewed anywhere in the Monterey area? If so, what shop or service did this for you?

I don't have personal experience with their hydros, but Pacific Coast Scuba in Morgan Hill Pacific Coast SCUBA - Your dive shop for your future has their own hydro facilities (they don't send the tanks out) and proport to be able to maintain the "+" status. I'd give them a call.

 

[Jim Kerr]

I'm just curious and wanted to see if anyone already knew...

Has anyone been successful in having an LP steel tank hydro'd and the "+" status renewed anywhere in the Monterey area? If so, what shop or service did this for you?

I'm looking to get the full capacity out of LP steel, but I understand that the "+" is often ignored during hydro, even if the customer requests it. Any info is a help, thanks.

I just had mine hydro'd last year. I was told that once it's hydro'd you lose the "+" rating which is 10% over fill capacity. To my knowledge there's no other choice.

 

[do it easy]

I just had mine hydro'd last year. I was told that once it's hydro'd you lose the "+" rating which is 10% over fill capacity. To my knowledge there's no other choice.

The tank has to pass a secondary criteria in order to get the + rating renewed. I'm under the impression that some requalifiers don't bother with the extra step. There is usually an "REE" stamp and number on the tank that the hydro tester will use to deterimine if the tank qualifies for the + rating. As far as I know, it's all paperwork and not actually an additional test.

 

[Aquabach]

I just had mine hydro'd last year. I was told that once it's hydro'd you lose the "+" rating which is 10% over fill capacity. To my knowledge there's no other choice.

This is a very common myth. Many people believe that once a tank has its first hydro it can no longer receive the "+" overfill. In fact more people (professionals included) think this than don’t. The fact is it’s untrue.

In 2000 I spoke directly with the DOT who in The U.S. regulates cylinders. The DOT told me a tank is not rated at a specific pressure and then becomes “less” rated. It either passes or fails. As long as the Hydrostaitic test is done with the correct pressure it will maintain its plus rating. The way a hydrostatic test is done is to overpressurize the cylinder in water and measure its elasticity by the amount of water it displaces. This is done with 5/3 of the tanks pressure. For example if you have a 3000 psi cylinder it is pressurized to 5000 psi for the test. (5/3 X 3000 = 5000)
If your plus cylinder was originally rated at 2250 with a 10% overfill in order to maintain that 10% overfill the test would have to be conducted at 4175 which is 5/3 of 2475. (2250 plus 10% or 225) If the hydro is only done at 5/3 of 2250 then it can only be filled to 2250 and you’ve “lost” your overfill rating. You could do the math for 2400 psi tanks it’s the same thing. I just choice the older tanks for my example

By the way, another piece of trivia some may like to know is why they have a 10% overfill anyway. I was told it came about during World War II when there was a shortage in most metals. The government decided to revaluate the rating of the cylinders. They decided that they could increase the pressure by 10%. Now the lawyers get involved. As I understand it, to actually change the rating (as in declare a tank was certified to 2475 instead of 2250) under the law at the time would take a change in the law and therefore an act of congress. But to “adjust” the rating the DOT could do that themselves and that’s why they did the 10% overfill. So why do we still have the 10% overfill? Beats me. Perhaps because of habit. I don’t know.

My advice to anyone with a LP tank is to ask the hydro guy to test it at the overfill pressure. If they say no, find another hydro business. You may have an uphill battle though. If your local dive shop doesn’t know any better they won’t fill it.

 

[Baconated]

I picked up two PST LP 80's from someone on ba_diving last year. He had them re-hydro'd and re-plus rated before selling them as they were 5 years old. I think he had it all done at Diver Dan's in Santa Clara.

Nathan

 

[kelpdiverguy]

Thanks for the responses so far. If anyone knows anything else please let me know. I'll get in contact with Pacific Coast Scuba and if anything develops I'll let everyone know.

 

[--tom--]

And the + rating can be reinstated. I have had two tanks that didn't get the plus then later, got the plus back. I have had some shops tell me "once gone always gone."

 

[vshearer]

On a related note. I just got a new Faber Blue Steel LP108. On the tank it is rated 2400 and has stamped "Do not overfill", but on the tag that came with the tank it states a working pressure of 2640, which is plus 10%. But there is no "+" on the tank. So how is a fill shop to know?

 

[zf2nt]

I'm just curious and wanted to see if anyone already knew...

Has anyone been successful in having an LP steel tank hydro'd and the "+" status renewed anywhere in the Monterey area? If so, what shop or service did this for you?

I'm looking to get the full capacity out of LP steel, but I understand that the "+" is often ignored during hydro, even if the customer requests it. Any info is a help, thanks.

MBDC, Bamboo Reef, and Aquarius all use the same hydro test facility in Salinas. That shop will do "+" testing for a very nominal additional fee. We charge $5 additional for it at Aquarius. As somebody else has noted here, whether the tank has ever had the "+" rating lapse is irrelevant to the current test.

Bruce