M24x2
Here are some answers to the questions :
The unfortunately technical standards for gas-tanks are as uncoordinated as the electric wall sockets. What in Germany is used for Helium and Argon, in Italy means Oxygen and what in Spain is used for Oxygen can't be found in Germany.
Diving is a global sport, so there is no chance for island-solutions. This mean standardization by facts, and so there are some unofficial international "standards".
The reason for different connectors is to prevent dangerous mistakes.
Divers mainly use the following gases:
The most Divers use nothing else than compressed air, that causes air-components to be cheaper and seduces to abuse the air-standard for other purposes.
It is a real bad habit to abuse Air-Coded Connectors for Oxygen-enriched or unbreathable Gases.
When you live in an area where 5/8" is not used to code compressed air, the German Air-Valve looks real nice as TEC-Dive Valve, BUT think about tourists from Germany.
A mix-up of gases can be deadly, therefore careless home mechanics should not take place. A normal Air-Regulator is unsuitable for oxygen (or rich EANx), to breath Argon can be fatal.
That brings us to the need to use 3 different connection-codes:
The usual connectors (in Germany) (Inner-/Outsidethread relate to the tank-mount) are for
The usage of R3/4" for Oxygen and Nitrox, as well as R1/2" for Argon has, besides that this is the obliged standard in Germany, the advantage to be cheap and easy to achieve in serial production. The regulator-manufacturer only has to, starting from R5/8"-Air-DIN, use other gas-code-nut's and to take care of using oxygen-compatible and clean materials for Oxygen/Nitrox usage (like Viton-O-Rings, Teflon-washers). Tank-valves with this codes are cheap and easy available because of mass-production for medical an technical applications. Only for manifolds you need a special production or have to use conversion-kit's.
Suitable Regulators are obtainable in specialised shops like UWtech and Submariner .
The muddle in the O2 and Nitrox area is a problem for divers and filling-stations, so it needs to co-ordinate the gas-codes with the dive-base then planing a travel, especially when you are the first who wants to get more than just air from them.
R1/2" does not mean 1/2" thread-diameter (~12,7mm), it is the name of the thread and specifies direction, diameter, ascent and shape. On top of it all R1/2" is only a nickname for the inert-gas-thread, it would be better to name it W 21,8 x 1/14" (clockwise) because it is a little bit greater than the 1/2"-Water-pipe-thread. Hydrogen in Germany also has W 21,8 x 1/14", but counterclockwise.
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M24x2 |
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Storage-Tank Connector-Codes
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Air |
O2 |
He |
Ar |
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Egypt |
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R5/8"BN |
R5/8"BN |
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Germany |
R5/8" |
R3/4" |
R1/2" |
R1/2" |
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Italy |
R1/2" |
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Sweden |
R5/8" |
R1/2" |
R24.32mm |
R24.32mm |
R5/8" and R5/8"BN are the only female Tank-Threads in this table.
R stands for Right = cw.
R5/8"BN stands for the same thread as R5/8" but combined the so called "Bull Nose" seat.
You may also take a look on the
color-codes.Caution, only handle the gases you are certified for, not all what fits mechanically is a safe combination!
No guarantee for the data on this page !!!
This essay was not only dedicated to movie-makers and other "tec-divers" because oxygen is a gas that should be found in any well sorted "first-aid-box" on dive-boats and -bases.
©
Karl Kramer 26.12.97