How to read DOT tank codes?

[ChrisA]

Is there an on-line refference some place that I could study so I could learn to read those codes stamped on tanks?

 

[neil]

Is there an on-line refference some place that I could study so I could learn to read those codes stamped on tanks?

http://diverlink.com/gear/tankmarkings.htm
http://scubatanks.us/markings.htm

You should have learned in OW class, you know.

Neil

 

[Kim]

http://diverlink.com/gear/tankmarkings.htm
http://scubatanks.us/markings.htm

You should have learned in OW class, you know.

Neil

It was in OW class - but the markings they use in the States are not the same as elsewhere!! I have a tank bought in Japan and it looks very different! How many regional differences around the world there are I have no idea.

 

[Drew Sailbum]

You should have learned in OW class, you know.
Neil

This is precisely the sort of minutae of detail that does not belong in an OW class.

Here are just a few of the common codes from my PSI Cylinder Inspection Course. I have to look up some of them from time to time, and can't imagine that a OW student needs to know more than a very small handful.
DOT = Department of Transportation (US)
ICC = Interstate Commerce Commission
CTC = Canadian Transport Commission
TC = Transport Canada
3A = Carbon Steel
3AA = Chrome Moly Steel
3AL = Aluminum
3ALM = Aluminum (Metric pressure follows)
3AAM = Chrome Moly Steel (Metric)
6498 = Alcan & Luxfer 6351 Al Alloy
7042 = Walter Kidde 6351 Al Alloy
6688 = Norris Industries 6351
6576 = Kaiser Industries 6351
9791 = PST High Density Steel
E = Exemption
SP = Special Permit
TP = Test Pressure
R = Repaired FRP
F = Failed Hydro or Visual
LND = Lined
M4002 = Catalina Cylinder
8303 = Faber Cylinder
WK = Walter Kidde
Cliff Div = Parker Cylinder
KAE = Kaiser Aluminum Engineering
6010 = SCI Aluminum Liner
SP 890 = Canadian AL

There are further codes on some cylinders which may specify its size. Unfortunately, these codes are not the same from one manufacturer to another.

 

[Ontario Diver]

A couple more...

REE - Rejected Elastic Expansion (Used by the H-test facility to test the tank - on steel tanks only)

SPUN - Spun neck

BTC - Military Markings

 

[Kim]

I'm just happy that my pressure gauge is supposed to read 200 bar when my tank is full - and that I'm supposed to leave the water when it's 50 bar. That's the main thing about tanks that I remember from OW. (oh yeah - better check the tank O-ring before I connect the first stage!!)

 

[ChrisA]

http://diverlink.com/gear/tankmarkings.htm
http://scubatanks.us/markings.htm

You should have learned in OW class, you know.

Neil

The above refferences appear to cover only Aluminum tanks. What
about high pressure composite, and the varous steel tanks?

They did cover this in OW but only briefly I think I learned about how to tell if a tank has had a recent hydro but not given the full breakdown of all codes that we might ever see on a tank. That's what I'm looking for.

 

[SDAnderson]

The above refferences appear to cover only Aluminum tanks. What
about high pressure composite, and the varous steel tanks?

They did cover this in OW but only briefly I think I learned about how to tell if a tank has had a recent hydro but not given the full breakdown of all codes that we might ever see on a tank. That's what I'm looking for.

I don't know of any reference that lists all of the codes used on all of the high pressure cylinders manufactured or in use around the world - it would be a big book and subject to constant change. If you're interested, I think the project is looking for someone to head it up.

If you have a specific question about your tanks, maybe it would be easier if you told us what tanks you have and what markings are on them. Somebody around here can probably help out. If not, we'll all pitch in and make up some answers for you.

 

[Ontario Diver]

The above refferences appear to cover only Aluminum tanks. What
about high pressure composite, and the varous steel tanks?

They did cover this in OW but only briefly I think I learned about how to tell if a tank has had a recent hydro but not given the full breakdown of all codes that we might ever see on a tank. That's what I'm looking for.

markings are the same for AL and AA tanks, with the exception of REE which is only on AA tanks.

As for composite (FCW) and Hoop Wrapped (HW), I don't know if any have been approved for underwater use, but they will all have a DOT/TC permit/exception number, serial number, working pressure, manufacturer's name and/or number, hydro date (optionally test burrett size and REE) on a label epoxied onto the tank. Follow on hydro testers will attach a label using the same format as stamping a AL/AA tank and then epoxy over it. These tanks are never stamped and require more knowledge to VIS than an AL tank.

 

[neil]

It was in OW class - but the markings they use in the States are not the same as elsewhere!! I have a tank bought in Japan and it looks very different! How many regional differences around the world there are I have no idea.

If I had a brain I would have noticed where you're from!

N