Why DIN Valves??

[lowviz]

eh?
since when?
mine works fine

Ok, I shot from the hip. I find that some firehouses can't handle the 300 bar fitting as it is too long to fit through the standard yoke they all seem to use and the 300 bar fitting also doesn't have the 'dimple' in the back. Bottom line is I can get a 200 filled anywhere, the 300's can be a problem.

 

[digital_steve]

it doesn't matter how long the stem is as long as it seals the oring
it just leaves a bit of stem thread showing

 

[Rick Murchison]

Quickly read through this thread, just want to note that 200 bar DIN's will work with a yoke adaptor, 300's won't.

This is correct. The 300 bar valve is too long for a yoke to fit around it (and lacks the dimple). This is an "on-purpose" design incompatability as yoke fittings have a max working pressure rating of 232 bar. If you have a DIN valve that a yoke adapter will fit, it ain't a 300 bar valve.
Perhaps you're thinking of the fill adapter... the brass block that screws into a DIN valve to allow a Yoke fitting to be used for filling - where the yoke goes around the brass block (dimple's in the brass block) rather than the DIN valve - now those will work on 300 bar. What we're talking about is fitting a yoke equipped regulator directly to the DIN valve with an insert, which can't be done on the 300 bar valve.
---
Just dawned on me that you may also be talking about using a yoke adapter on a 300 bar DIN fitting on a regulator, to adapt the regulator for use with a K valve... that'll work, absolutely.
Yeah, reading back over the posts I see that what we really had was a failure to communicate... lowviz is saying a yoke won't fit a 300 bar DIN valve (he wrote fitting but meant - described - a valve), which is correct, and Steve's saying a yoke adapter will work with a 300 bar fitting, which is also correct!
Glad I could clear that up for y'all... uh, me.. uh..

Sheeeeesh!
Rick

 

[digital_steve]

Communication... so important
Now, how can i signal "this fitting won't work on a 300bar tank" with my light?

 

[Shcubasteve]

I have 4 AL80s w/ DIN combo valves, giving rise to the original question. On a similar note.... Its well known that most tank rentals will have K valves, so my next question is this: Is it safer/more reliable to have a standard K valve and yoke reg, or use a DIN reg with a yoke adapter for rentals??? seems like the added adapter is an added failure point ??

 

[JahJahwarrior]

I used to think it didn't matter that much, even though I did switch to DIN as a cave diver.



Then a buddy had a tank fall over with his regs attached. Yoke regs. The yoke got mangled enough that it was unable to connect to the tank correctly. Fortunately the valve was off when he dropped it....but I don't plan on using any more yoke regs, save for one aluminum 40 which I'm gonna switch over soon here

 

[DA Aquamaster]

Pete and northwoods diver pretty much got it but there are a few things to add.

For clarification, 200 (actually 232 bar) DIN valves can accomodate a K valve insert to allow the valve to be used with a yoke reg, a 300 bar DIN valve cannot as it is two additional threads longer and is too long for the yoke to fit over it.

The longer 300 Bar DIN valve is also however more damage prone as if the tank falls over the longer unsupported section is likely to be bent to more of an oval shape.

300 BAR valves are not stronger than 200 bar valves, both woudl handle the 4350 psi allowed by the 30 bar valve, the reason for the difference was to prevent lower service pressure 200 bar reguators from being attached to a 300 bar tank as the deeper 300 bar valve would not allow a 200 bar reg to seat. 5 threads or 7 makes no real difference as the odds are not more than 3 threads are in full contact anyway.

If properly designed and executed a yoke valve o-ring is also fully captured. The problem arises with lightly constructed yokes that may stretch at very high pressures and more commonly with yokes not being securely tightened. When that happens the extra room can allow the o-ring to extrude. However the same thing can happen with a DIN reg, and on an unpressurized deco reg a DIN valve is in my experience slightly more likely to become loose than a yoke reg. The difference is the location of the o-ring and what happens to it. On a yoke valve, the o-ring is on the face of the valve and will be blown off. With a DIN valve, the o-ring is seated in the regulator and usually does not go anywhere allowing the reg to be easily resealed.

As pointed out previously, the lack of a yoke knob greatly reduces the tendency to snag line and other potential entanglement hazards.

So in short, I am believer in the 232 bar DIN valve as it allows the use of DIN regs on 3442-3500 psi tanks and the convetible aspect of the valve allows it to be used with yoke regs as well. The 3442 versus 3500 psi limit is arbitrary but with the virtual dissapearance of newly made 3500 psi tanks, it will I think be a moot point in the future. Similarly, the increasing commoness of the 232 bar DIN/K valve will eventually solve the "traveling diver will encounter a yoke valve" problem.

Consequently, I don't forsee a situation where I would buy a valve that was not of the 232 bar DIN/K variety.

 

[Rick Murchison]

...So in short, I am believer in the 232 bar DIN valve ... Consequently, I don't forsee a situation where I would buy a valve that was not of the 232 bar DIN/K variety.

Me too
Rick

 

[lowviz]

Communication... so important
Now, how can i signal "this fitting won't work on a 300bar tank" with my light?

Slashing across neck with light beam.

-sorry about the fitting/valve thing...

 

[lowviz]

Alright techies, I’ve got a question…I am a very active recreational diver who likes to take advice from technical divers… I am about to get a new regulator and am debating DIN fittings VS traditional yoke…. I am under the impression that DIN valves are more failsafe, and therefore more reliable then a standard yoke valve. Is this a correct assumption?? I know they can handle higher pressures and are better for HP cylinders, but are they safer to use then yoke???

Thanks all and Dive safe…

Steve W

I'm not tech yet, but borrow heavily from them. There is a lot of good DIN info in this thread. I was going to let it go at my last post, but noticed that my OLD DiveRite H-valve has a '300' bar valve AND a dimple -go figure. So you can't just look for dimples and expect to get '200' bar valves.

To your orginal post:
I find that DIN is simpler, cleaner profile, and solves the lost O-ring issues that yoke valves present. I've never had a problem with yokes, so I can't speak to reliability.