Yoke vs. DIN for stage bottles

[ArcticDiver]

Just a piece of information for your decision making:

There are different sizes yoke valves/adapters. So, as was pointed out to me, DIN is DIN everywhere. But there are at least two different sizes yoke valves/adapters. One person claims there are three. I've only personally experienced two. But, I rate his reliability very high.

So, if you want to be sure what you have fits and is the most secure; use DIN. Otherwise, be sure in advance the yoke regulators/adapters you have will fit where you are going.

Much simpler just to do DIN.

 

[bubbleblowindude]

To add to that, this is not a case of "To introduce a failure point with the rationale that "WHEN it fails I can more easily change it"." They weren't talking about changing regs due to a yoke failure; the very point was of a failure happening regardless yoke or DIN that requires a reg change, and in such case, which is faster/more reliable/more secure.

Thanx for the clarification (grin) I know "they" weren't suggesting that the change of regulators would be due to a yoke failure....I was suggesting that the nature of a yoke-to-valve connection places the o-ring in a position which is succeptible to a lateral pressure such as a "bump" from the side which could cause the o-ring to fail and subsequently "free-flow". BTW, if this were the case, switching to another "yoke" style reg wouldn't help since the o-ring is integral to the tank valve. Inversly, a "DIN" reg captures the o-ring securely and is not so succeptable to the same dislodging issue. (Thereby minimizing the need for a "cure" for a non-existant disease) Also, the second reg, (if needed to switch) has its own o-ring. Bottom line is this, there are procedures in place to assure a properly functioning deco assembly, and if a diver reaches the level of training which allows for the use of 4 deco bottles, perhaps his choice of open circuit should be re-evaluated?

 

[Flightlead]

What kind of training are you in right now? I think knowing that will focus the discussion a little more.

right now I'm simply in the NAUI NTEC program, trying to explore the why's and wherefore's. Interests lie in both deeper wreck and cave. Expecting to be in tech nitrox/deco procedures by the end of '08 and possibly cavern/cave 1 soon too.

 

[rjack321]

What about backgas regs? What do your buddies/classmates have? Having interchangable gear is very helpful when a reg poops out before a dive and you can swap stuff around with your buddies in <5mins and continue.

Is the instructor requiring you to have yoke stage regs?

Or was this class discussion/recommendation for yoke just a passing recommendation based on how he/she dives?

 

[texdiveguy]

I have DIN regs and valves on my stages. My tech instructor recommends yoke valves. What do most people use?

I have not taken the time nor will I to read all the pages of chatter on this thread. I use DIN regs on all my cylinders (deco-back-stage). I am not sure the reason your instructor would want yoke set-ups instead of DIN....but plainly DIN's are the preferred reg to valve connection for technical diving.

 

[Jeff Toorish]

This is kind of funny --several people (you know who you are) have said something like, "din only, but I have yoke converters just in case..." So, you know, technically, wouldn't that mean you have used yoke?

I mean, once you put a yoke converter on a din valve and slap that baby on a tank with a yoke fitting --that's pretty much a yoke first stage at that point --only it has two failure points.

Just a thought.

Jeff

 

[DeepSeaExplorer]

There are still a few old school divers out there, and yes some of them are instructors. However, very few serious tech divers still use Yoke, especially in cave due to the way line tends to get wrapped around that knob. I get concerned when I see Yoke valves used in tech diving.

 

[Meng_Tze]

This is kind of funny --several people (you know who you are) have said something like, "din only, but I have yoke converters just in case..." So, you know, technically, wouldn't that mean you have used yoke?

I mean, once you put a yoke converter on a din valve and slap that baby on a tank with a yoke fitting --that's pretty much a yoke first stage at that point --only it has two failure points.

Just a thought.

Jeff

Yes, but it is not because it is set out to be using Yoke. But in case a DIN valved tank is not available. I would have no issue with a yoke tank on stage/deco, but not as backgas in the tech diving I do. For ease of use and interchangeability, many resorted to DIN exclusively.


Different nuance.

 

[DA Aquamaster]

There is nothing wrong with thinking things through in advance - except when that thinking gets wasted on non-productive arguments about contingency plans that are born losers to start with and prevent productive thought on plans that actually work to keep you out of trouble to begin with.

Consequently, I am not a big fan of the whole "swapping regs" under water idea as there are better ways to plan and deal with a deco bottle reg failure that do not involve the risk that your just swapped and freshly flooded reg may also not work or that the regs involved will both need to be serviced and dried before being used again.

1. I do my gas planning so that in the event I lose any one deco gas, I can finish the dive safely on the remaining gas(es). This means if I am using two deco gases, I have contingency plans to finish on the remaining deco and back gas. If I am doing a single deco gas dive, I will have a contingency plan to finish the dive on the reserve back gas if the sole deco gas is lost. This lost gas contingency planning extends to the next deeper/ longer bottom time contingencies as well.

2. Proper choice of a simple bullet proof "flow by" piston design deco reg goes a long way toward ensuring that a deco reg failure will not occur in the first place.

Consequently, in order to entice me to swap regs between two deco bottles or between my back gas and deco bottle, either an awful lot would have to go wrong beyond just a deco reg failure or there woudl need to be extenuating circumstances such as I absolutely need to do the full accellerated deco as a storm is kicking up and the boat wants to leave sooner. The latter is less likely to happen as if it is a likely possibility, I'd plan to restrict the bottom time to reduce the deco in the first place.

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Contrary to popular opinion, yoke valves are also a metal to metal fit (assuming a suitably heavy yoke is used that does not stretch at the service pressure being used) just like DIN valves, so the DIN is more secure argument is a little flawed. Yoke valves are also less prone to spinning themselves loose underwater than DIN valves.

This is a good thing as on the other hand the o-ring in a yoke valve is more likely to get extruded or blown out if the fitting is not tight, so there is not always a second chance to retighten the connection and repressurize the reg underwater as is usually the case with a DIN valve where the o-ring is not likely to be displaced if a loosely connected reg is pressurized.

In addition yoke valves have an exposed face that is more prone to damage.

Finally, the knobs on yoke regs are magnets for line and line tangles are both more frequent and harder to clear by yourself than with DIN valves.

 

[Mike Edmonston]

I don't know if anyone brought this up yet, but a yoke reg is only rated at 3000psi, while a DIN reg is rated at 3500 psi. That's because of the o-ring, not the first stage.

Therefore, if you want to carry the max gas safely, (more than 3000PSI) you HAVE to use DIN.

Are you going through the NAUI NTEC program now? NAUI does NOT teach the use of yoke regs in pressures over 3000psi. Are you sure you understood your instructor correctly?

Cheers