DIN Conversion

[fjpatrum]

I recently bought some HP100 tanks specifically to get more bottom time on an upcoming trip. These tanks have 300 bar DIN connectors on them and my regs are yoke. So, now I'm going to buy the DIN conversion kits for the regs (SP MK10 and Aqualung Titan).

I assume this is a fairly easy conversion for anyone comfortable taking a first stage apart. Anything I should be aware of beforehand?

 

[Hickdive]

Some regulators are not designed for 300bar supply pressure which often requires back-up rings to support o-ring seals. So it sometimes isn't simply a matter of swapping out the yoke for a DIN connection.

Check the manufacturers' drawings and recommendations before proceeding.

That said, it would be unusual for "HP" cylinders in the US to have a charging pressure of 300 bar. Usually the "HP" designation is given to 232 bar cylinders and there are two versions of G5/8 DIN connections available; one for 232 and the other for 300. Count the DIN threads on the cylinder outlet to be sure of what version you have.

 

[rhwestfall]

you don't get into the "innards" at all;

you need a way to secure the stage (thread it into one of the ports, and then hold it in a vise. From there, it is typically a socket wrench to remove the yoke nut, and a torque wrench to set the new one. Here is the schematics for the SP MK-10:

http://www.frogkick.dk/manuals/scubapro/Schematics/1. Stage/

aqualung:

http://www.frogkick.dk/manuals/aqualung/

 

[fjpatrum]

No, the tanks aren't actually 300 bar, but the valves are so I figured I'd just get the 300 bar DIN converters to make sure they mate properly. I believe I read somewhere that the threads are different for the different pressure ratings, though that may not be the case here?

Thanks for the details, Bob. I don't have the schematics with me here but do at home. I just hadn't had a chance to look at them yet. I figured it was that easy but figured I'd ask since it's slow here at work today.

 

[rhwestfall]

the SP universal din conversion is 300 bar. It will work with 232 bar valves, but the opposite is not true. The difference between 232 and 300 is the thread depth. I can't help you on the Aqualung.....

 

[JohnN]

No, the tanks aren't actually 300 bar, but the valves are so I figured I'd just get the 300 bar DIN converters to make sure they mate properly. I believe I read somewhere that the threads are different for the different pressure ratings, though that may not be the case here?

300 Bar DIN valves have more threads, not different ones. I've never seen a 1st stage that wouldn't work in both 200 and 300 bar valves, but that may just be my inexperience.

 

[kwinter]

300 Bar DIN valves have more threads, not different ones. I've never seen a 1st stage that wouldn't work in both 200 and 300 bar valves, but that may just be my inexperience.

DIN connections have a captured o-ring that must contact the back of the valve. 300 bar valves are deeper and have more threads. There are some 200 bar regulator connections that would therefore not reach the back of the valve to provide a seal. 300 bar reg fittings are longer so they reach the back of the valve. That's why you can use a 300 bar reg in a 200 bar valve, but not vice versa. Picture trying to bottom out a half-inch screw in a one inch hole.

 

[Jonno]

Convert your regs to DIN. Less agro all round.

 

[herman]

Finding the conversion kits (MK-10) and the adapters (AL) may be a bit difficult and no doubt expensive. Plus it then requires you to restore or buy more adapters if you travel with your regs. Why not take the alternative approch and replace the valves with yoke or yoke convertable valves? You did not say what the rated pressure of the tanks are but unless they are 4K (good luck getting them filled) there is no reason not to use modern yoke regs, any of them will easily handle 3500 psi.

 

[Peter69_56]

I converted 4 Oceanic CDX-5 regulators to 300 BAR DIN, found it simple. The hard bit was finding the converters at a reasonable rate. For a short length of pipe and some O rings and a piece of plastic it cost me $75 each which was better than the Aussie price of $145 each. I see that scubapro sells their converters for around $25-30 which seems reasonable. Also the CDX-5 body had stamped on it 300 BAR.

I suspect most if not all regulator bodies are rated at 300 BAR and they just change the tank connector to suit the requirements. In this way they only have to tool up for 1 body for each model. Thus cutting costs. That you have a 300 BAR regulator body with a 232 BAR K valve attachment is of no consequence.

232 BAR DIN 5 threads (fits 232 BAR DIN valves only)
300 BAR DIN 7 threads (fits 232 and 300 BAR DIN valves)

I have all my regulators 300 BAR DIN so I can attach to any cylinder with DIN or K (using a converter). This way it doesn't matter what valve is on the cylinder I can attach to it. Have found in most parts of the world now, they have DIN valves with inserts available so one can use any reg on them (but I believe USA territories are somewhat restricted to mainly K valve ????????). Without getting into the normal K vs DIN argument, I prefer DIN for a number of reasons, and technical diving is usually expected to be on DIN, hence my change to DIN, but each to their own.