Help Identifying Steel Tank

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TectonicDrake

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Location
Minneapolis
# of dives
25 - 49
I just got some tanks used from a friend. Having difficulty identifying them. it's a round-bottomed steel. ICC-3AA2250 HN 1306 then some other stamps that look like diamonds and a 7 diamond 64. I can include pictures. dimensions are also odd. I'll get a tape measure on it as soon as I can. I believe it's the normal diameter/circumference for a steel 72 from that time period but it's about 4 inches taller iirc.
 
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Looks like there is an N inside that diamond which would be Norris Industries as tank manufacturer.
The 7 diamond 64 would be a birth date of the tank, july of 64 with possibly the Norris stamp(diamond).
the A looking stamp should be the independent inspector - "Authorized Testing".
Clean it up and have fun!

Update: another thread on here has a spreadsheet they did to work out a ree value. If you find a hydro place that will accept that data then you can get it + stamped. I have two norris tanks, but my hydro guy won't accept anything other than manufacturer data on the specific serial number (i.e. no + stamp for me until I find a new hydro guy).
 
kind of a newbie to owning my own tank. What do you mean by + stamped and work out a ree value? I'll see if I can find the link and make sense of it. Would that be a + stamped next to the hydro date? Because they gave me that at the hydro shop.
 
Looks like 28.5" from the bottom of the tank to the neck where the valve screws in and 7" diameter or slightly over I'm having to eyeball that a bit.
 
kind of a newbie to owning my own tank. What do you mean by + stamped and work out a ree value? I'll see if I can find the link and make sense of it.
3AA engineered steel cylinders are in theory eligible to be filled 10% over design pressure if they meet certain hydrostatic test standards.
e.g 2250 psi become 2475psi IF it has a + after the current hydro stamp

The US DOT specifications to meet the + criteria are fairly complicated formulas which rely in part on wall thickness and tensile strength and other values which the shop monkeys at the hydro facility don't have. And they don't want to deal with that, they want a single yes/no number.

To avoid all that messy math, cylinder manufacturers started (about 15-20 yrs ago) stamping the number on the tank which meets the allowances for a + stamp
How is the REE number on a tank used

Older cylinders (this one is from 1964) don't have REEs printed right on the crown so if you really want/need + you have to find the paperwork to give to the hydro shop documenting the REE.
 

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