How do these steel tanks look?

[MrChen]

I've got a guy who wants to trade me some tanks. The item I have I'm trying to sell for $750. I'm willing to trade for a pair of steel 100's, but I'm not overly excited about the condition of these tanks. They have a current hydro/viz. Since I'm balking, he's thrown in a 3rd tank and all new valves.

Worth dealing with? These would be my first steel tanks and the signs of rust have me worried.

On one tank I see the words Japan stamped on it, found that curious.

Thank you in advance for taking a look and providing feedback.

 

[Glenn08]

I was concerned by "spun", but that was a problem with aluminum tanks. The hydro test stamp looks both current and U.S. which is good.

 

[KD8NPB]

They're Asahi HP steel tanks, imported by Sherwood. Asahi tend to be pretty negative...-4 empty, -12 full.

Tanks of this vintage, I would probably pay $100-$160 ea used locally.

The good news is that they have passed visual hydro and visual recently.

 

[Herb-alaska]

I've got a guy who wants to trade me some tanks. The item I have I'm trying to sell for $750. I'm willing to trade for a pair of steel 100's, but I'm not overly excited about the condition of these tanks. They have a current hydro/viz. Since I'm balking, he's thrown in a 3rd tank and all new valves.

Worth dealing with? These would be my first steel tanks and the signs of rust have me worried.

On one tank I see the words Japan stamped on it, found that curious.

Thank you in advance for taking a look and providing feedback.

There is nothing showing in the pictures that give me pause about the tanks HOWEVER there is lots that you can't see in the picture. The tank I could see has a birth date of July 06 and appears to be HP 100. Steel tanks have issues if not taken care of under the boots. You need to take the boots off each tank and have a look. If you are concerned I would also open them up and have a look or if you aren't sure take them in for a current viz it may cost you 60 bucks but it may save you a lot too.
Again there is nothing in the pictures that makes me concerned steel tanks last forever if they are taken care of which means rinsed including under the boots and filled with dry gas.

I would be interested however I feel they are worth about 600 not 750.
Just my opinion and I am certified to do viz inspections and I do all my own however this is just my inexpert opinion
Herb

 

[Dr. Lecter]

What signs of rust? Where someone stamped the piss out of it with a hydro date? That's nothing. Have the insides VIPed - if they're not rusty, they're golden. Ditto on checking under the boots, though hot dipped galv usually has less of a problem with that than painted.

I agree that they're not of equal value if what you're selling would actually go for $750, though. [-]Maybe $500ish, though I see fully assembled double sets going for $500-550 and that includes bands and nice manifolds.[/-] Just saw the comment above about which specific type of steel 100s these are, and unless you usually dive with a lot of lead I'd either pass on these or tell the guy they're only worth $100 or so a pop. -4 per tank empty is really negative for a HP100.

Also, IIRC, some of these old Sherwood imports had problems with getting their REE figures without some kind of special procedure that essentially involved pre-stressing the tank before the actual hydro test. While I also think that's common practice for all exemption hot dipped galv tanks, the difference is that with say a Worthington you have paperwork you can send along with the tanks that shows the exact procedure the hydro facility is to follow along with the DOT rules/regs that back it up.

 

[rhwestfall]

Seeing that new HP100's are $400-ish (and with some hard work, can be found for less), I don't think he is making that sweet of a deal to you...

 

[Keith.M]

I am curious about the Nitrox sticker.

"CLEANED FOR PREMIX OXYGEN CONTENT 22 TO 40%"

That sounds like banked nitrox and not partial pressure filled. You should be able to fill any tank with banked nitrox.

 

[rhwestfall]

:lol: Nice catch!

 

[Jim Lapenta]

I am curious about the Nitrox sticker.

"CLEANED FOR PREMIX OXYGEN CONTENT 22 TO 40%"

That sounds like banked nitrox and not partial pressure filled. You should be able to fill any tank with banked nitrox.

Wrong. That part of the sticker has not been punched. What has been is that the tanks are O2 clean. Which means squat after the first fill since you never know what was put in them. But the stickers as punched are ok for partial pressure blending. IF the other sides had been punched then only banked stuff should be put in them. But you don't even need that for banked up to 40%.

 

[Scared Silly]

I am curious about the Nitrox sticker.

"CLEANED FOR PREMIX OXYGEN CONTENT 22 TO 40%"

That sounds like banked nitrox and not partial pressure filled.

Correct, of course there is no such such thing as premixed NITROX. NITROX means a mixture of O2 and N2 that is used for breathing. The term has nothing to with how it is made. NITROX can be made by PP blending, via continuous blending, or from a membrane system. All of which can then be banked.

Overall both stickers are BS and just another example of the piss poor self regulated scuba industry when it comes to cylinders.

You should be able to fill any tank with banked nitrox.

Actually not, as there is no standard for the filling an non O2 cleaned cylinder with banked nitrox. Yes many shops do it, yes they get away with it, but there are safety issues.


For the OP. IMHO the cylinders are worth at most $200 each. IIRC Asahi cylinders are 3500psi cylinders which mean 7/8" UNF thread and 300 bar DIN only valves. So you can not put a 3/4 NPT valve on them and use a yoke reg. The other cylinder looks to have an REE value but I see 3442 which would be an exempt cylinder. So I am confused.