Yoke 1st stage with HP100

[asckar]

All,

What's the word on using a yoke first stage with a HP100? All my regs have a yoke first stage and I currently use either AL80's or LP95 but would like to move up to HP100. Switching my regs over to DIN is just not financially possible right now. I know that most steel tanks come with the Pro Valve thing that can be configured to either DIN or yoke but is using a yoke on a HP tank safe? Thoughts?

Thanks,
Safe and Happy Diving
Adam

 

[drdaddy]

All,

What's the word on using a yoke first stage with a HP100? All my regs have a yoke first stage and I currently use either AL80's or LP95 but would like to move up to HP100. Switching my regs over to DIN is just not financially possible right now. I know that most steel tanks come with the Pro Valve thing that can be configured to either DIN or yoke but is using a yoke on a HP tank safe? Thoughts?

Thanks,
Safe and Happy Diving
Adam

My favorite tanks are the HP 3442 steel 100s, second are my HP 3442 steel 80s. I use these all with yoke first stage. No problem at all in a couple hundred dives.

 

[WD8CDH]

There are very few modern yoke regulators that can't handle 3442 psi. Some are stamped 3000psi but that is usually a carry-over from the very old CGA-850 standard for SCUBA yoke valves. The newer ISO standard allows for much higher than 3000psi use. In fact, I have several yokes stamped both 3000psi AND 232 bar. I also have several stamped 3500psi, a couple stamped 4000psi and one stamped 4500psi.

 

[halocline]

I've connected an old doublehose yoke to my HP100, I'm still here to tell the tale.

 

[rstofer]

It's one of those judgment calls. All of our newer regulators had yokes stamped 3500 psi. No problem. Except, for uniformity, I converted them to DIN anyway.

However, all of my Oceanic Omega II's had yokes stamped 3000 psi. I picked the one I planned to use and converted it to DIN. In my view, if the yoke is stamped 3000 psi, some engineer designed it to withstand 3000 psi, not 3500 psi. That's a rather rigid interpretation but I'm a retired engineer.

The double hose reg I use in the ocean has been modified (Phoenix nozzle) and is capable of handling 3500 psi. The others get used on 3000 psi (Royal Aquamaster) or 2500 psi (Mistral).

I guess I'm just not going to push the envelope.

Richard

 

[WD8CDH]

<snip> In my view, if the yoke is stamped 3000 psi, some engineer designed it to withstand 3000 psi, not 3500 psi. That's a rather rigid interpretation but I'm a retired engineer.
Richard

So how would you interpret a yoke stamped both 3000psi and 232 bar?

 

[GrumpyOldGuy]

Out of curiosity, does anyone have any experience with a yoke actually failing at 3500PSI or less?

It may be that the yoke itself if plenty strong, but they are stamped at 3000PSI for marketing purpose, CYA legal reasons or the internal limits of the reg design rather then the limits of the mechanical connection to the tank. I DO NOT KNOW THE ANSWER - JUST ASKING!

 

[rstofer]

So how would you interpret a yoke stamped both 3000psi and 232 bar?

I'd probably go with the 232 bar. After all, that a factory rating.

Everyone gets to make their own choice. I chose to convert to DIN.

Richard

 

[scubafanatic]

...I'm still trying to concieve of how it would be possible to crack/rupture a yoke reg without the little tank-to-reg O-ring extruding/popping/tearing up and releasing the pressure LONG before you'd begin to stretch/fracture the METAL yoke reg ???

 

[WD8CDH]

Your right. It's more a matter of the yoke stretching enough under pressure to allow the o-ring to extrude than it is for the yoke to fail or be damaged.

Cousteau used off the shelf Spiro Mistral double hose yoke regulators at 5,000psi.