What is DIN/Yoke......

[TwoBitTxn]

I think I have figured out all the talk about DIN and Yoke attachments are first stage. What are they? What are their advantages and disadvantages? I honestly don't pay much attention to all the new stuff comming out. I dive with a scubapro MK200 first stage and it works for me.

Tom

 

[TexasMike]

DIN is a "threaded" method of attaching your first stage to the tank valve. This is most often seen in Europe and when using some higher pressure tanks and more technical applications. The "K" valve (or yoke) is what you have now.

 

[scubabunny]

Another question...I know the DIN valve allows the tank to be pumped up to a higher pressure, right? Is it the valve itself, or can it only be put on certain tanks? I mean, can you put a DIN valve on ANY scuba tank and pump it up? Or do I have it completely confused?????

 

[herman]

Hi SB,

The answer is that BOTH the valve and the tank have pressure rating and the LESSER of the pair determine the max pressure of the tank/valve combo. Assuming the tank neck and valve threads are compatable, any tank/valve combo is possible but again, the overall pressure rating is the rating of the lower of the 2. IE, a 5000 psi DIN valve on a 3500 psi AL-80 still gets you a 3500 max system or a 3500 psi yoke on a 5000 psi tank still has a max limit of 3500 psi. Now let me make it even more confusing. I have a yoke valve rated at 5000 psi. If I put it on a 5000 psi tank, can I use it? NO!! The yoke of my reg, Zeagle ZD-50, is rated at 3500 psi (DIN for the reg is rated at 4500 psi)so even if I have a 5000 psi tank/valve combo, I am still limited by my reg connection, be it yoke or DIN. In short, the lowest rating of any piece of your tank/valve/reg limits the max pressure of your system.

 

[devjr]

Scubabunny, in case you were confused by the above, the rated pressure is stamped on the tank, this pressure limit is mandatory regardless of valve. You didn't say what country you are in. However, for the US, the yoke valve is standard for tanks rated up to 3300 psi; the DIN valve is optional. Tanks which carry a higher pressure rating are fitted with DIN valves only. It can be shown that this type of lockup is more secure at super high pressures, hence this is industry practice. In summary, tanks rated 3300 psi or less may be fitted with yoke valve or DIN. Tanks rated above 3300 psi are fitted with DIN only.

 

[Lost Yooper]

A little more info for you. You can use a 300 DIN reg on a 200 OR 300 DIN valve. You can't use a 200 DIN reg on a 300 DIN valve. You can get a yoke plug insert to screw into a 200 DIN valve (not a 300 DIN valve) and use a yoke reg on it.
A 300 DIN valve and reg combo is often used by technical/overhead divers because it's more secure than either the 200 DIN or yoke connection. I use the 300 DIN Sea Elite manifold and 300 DIN regs on my LP 95's.
As far as pressures go, the numbers above are probably correct, but it really depends on the burst disk ratings anyway since they'll go before anything, followed by the neck o-ring, then the valve.

Mike

 

[gregor]

hi guys,

DIN means "Deutsche Industrie Norm" which tranlates "German Industrial Norm". DIN is a standard similar to what the IEEE does on computers / electronis etc. You have DIN-standards for papersize (f.e. A4 rather than letter), screws, anyhing you can think of.
Since the Germans are quite some foljs who do *everything* not 100% but 150%, the DIN-screw pretty safe stuff.

BUT:

If you don't want to dive in Europe but in US or Asia (what I prefer), most of the tanks are coming with a Yoke-screw, and you cannot attach your DIN-reg there. you can get an adapter for this, but this is additional weight and you have to spend additional money for it.

Since I want to get a reg myself and I'm living in Cologne, Germany, I will have to get a DIN-screw plus adapter since I also would like to rent tanks here (own tank doesn't make sense taking it on the airplan... ;-)

ok, just my 0.02$....

gregor

 

[scubabunny]

Ok...thanks guys...I'm still confused, but not as much. I live in Guam, and we only get a few DIN valves coming through our shop to get filled. I work in the wholesale department of a dive shop, and have had a few inquires about DIN valves and DIN first stages, and really had no idea as to what it was or what it did! I just didn't want to sell someone something they couldn't use.

So, basically, if you put a DIN valve on a compact 60cuft tank, it still doesn't increase the PSI of the tank, right? Still stays at 3300psi? *feels really stupid right now..this is why I majored in English in college!*

 

[Lost Yooper]

The tank is stamped with a pressure rating which isn't supposed to be exceeded -- especially with AL tanks. The only real advantage for putting a DIN valve on an AL tank would be to have a more secure connection than a yoke.
LP steel tanks are different story in the real world, but "legally" it remains the same -- don't exceed the stamped pressure rating. The PADI police might gitcha if you over pressurize steel tanks ... laughing.

Take care.

Mike

 

[devjr]

Scubabunny, if there is a demand for DIN valves, just remember that there are two basic types in the US market that your shop will likely have to recognize. The one, a "low pressure" type, can be fitted to tanks with pressure ranges of 1800-3300 psi. It can easily be recognized by the large threaded boss on the bottom of the valve. It is the size that is seen every day and fits all US aluminum tanks plus various US steel tanks even if imported. The other type DIN valve has a small thread size and only fits high pressure tanks. This would be the PST-Genesis steel tank or similar which is rated 3500 psi and has a small extended neck. There are different specs for other countries and there is a valve with a special size to fit 4500 psi tanks but I doubt that these will be seen frequently. If your customer orders a valve, make sure the thread size is correct and burst disc carries the correct rating. This is something that a technician(equip. repair guy) should check.