is a 300 bar tank with a 232 bar valve ok?

[Diver0001]

I absolutely and 100% stand by my statement that it will fit, and hold 300 bar. But yes I agree that using a yoke with 300 bar is not a good idea, and not just because of the o-ring extrusion, but because most yokes aren't built for that pressure.

IN the mid-70's yokes weren't built for that pressure and some even broke.

Anno-2011 I would be very surprised if the yoke broke.... but I would also be very surprised if the o-ring remained seated.

O.P. go ahead and use it, but keep the fill pressure to whatever the yoke is rated for, probably 232 bar.

Well... if he does that then there's not sense in choosing for all of down-sides of 300bar tanks now, is there?

I really don't understand why people need to fit a round-peg into a square-hole. There are solutions that are engineered to work together... so USE them!

R..

 

[Jimmer]

He asked if it would be safe to use his yoke reg on a 232 bar valve in the 300 bar tank until he gets around to converting the reg to DIN. So I gave him an answer. Does it make sense to have a 300 bar tank underfilled? Maybe not, but at least he can use it until he gets the reg switched over.

IN the mid-70's yokes weren't built for that pressure and some even broke.

Anno-2011 I would be very surprised if the yoke broke.... but I would also be very surprised if the o-ring remained seated.



Well... if he does that then there's not sense in choosing for all of down-sides of 300bar tanks now, is there?

I really don't understand why people need to fit a round-peg into a square-hole. There are solutions that are engineered to work together... so USE them!

R..

 

[Leadking]

First of all, I am not fully aware of thread standards in the land of Oz. I would assume that if the 200 bar valve can properly thread into the tank (300 bar in the US uses 7/8 inch threads while a 200 bar uses 3/4 inch threads) that the use the manifold would be safe AS LONG as a 200 bar regulator fitting OR a 300 bar rated yoke is used. The danger here, is the use of a regulator or yoke assembly not rated for the higher pressure.

 

[Diver0001]

He asked if it would be safe to use his yoke reg on a 232 bar valve in the 300 bar tank until he gets around to converting the reg to DIN. So I gave him an answer. Does it make sense to have a 300 bar tank underfilled? Maybe not, but at least he can use it until he gets the reg switched over.

You can use bandages to cover a wound too but that doesn't make the wound disappear....

You may be (probably are) right that he can ... under some limited parameters... use this as a stop gap measure... but you won't hear me call it "clever"..... on the contrary....

My father always told me, "you can do things the quick way or you can do things the right way... and only the right way will last". Expedience is usually a recipe for problems.

R..

 

[Jimmer]

Diver0001, I'm not saying its an ideal fix, and I quite agree with you that the best course of action is to convert the reg, but as a temp solution, its fine.

Look at it this way, if it were unsafe to put the yoke insert in the 200 bar valve and use a yoke reg on it, why would the valve manufacturer subject themselves to litigation when it fails and somone dies. I have used the inserts to "save a dive" before, when I left my DIN reg at home, borrowed a yoke reg from a friend, and just popped the insert in the valve. Provided the tank pressure is fine for the reg, there is no prob.

 

[DevonDiver]

Perhaps the US has different tank valves. The 300 DIN valves I am used to would not allow a 200 DIN regulator (or DIN adaptor) to work. There are more threads in a 300 DIN valve, which means that a 200 DIN regulator wouldn't reach the back to secure the O-ring. If the (200 DIN) adaptor was screwed all the way to the back of a 300 DIN valve, then it would be recessed, preventing a seal to be made when you attached a 200 Yoke regulator.

 

[Jimmer]

Perhaps the US has different tank valves. The 300 DIN valves I am used to would not allow a 200 DIN regulator (or DIN adaptor) to work. There are more threads in a 300 DIN valve, which means that a 200 DIN regulator wouldn't reach the back to secure the O-ring. If the (200 DIN) adaptor was screwed all the way to the back of a 300 DIN valve, then it would be recessed, preventing a seal to be made when you attached a 200 Yoke regulator.

You're absolutely right. We are talking about removing a 300 bar valve, and replacing it with a 200 bar valve so he can use a yoke reg on that tank.

Also, for what its worth, we dont have 200 bar DIN regs in US/Canada, all our DIN regs are 300 bar.

 

[naick]

Since I'm from the states, I'm going to convert to psi, so.....

A 300 bar valve is thusly rated to 4351 psi, while a 200 bar valve (which is actually a 232 bar) is rated to 3364.9 psi.

To my knowledge, the highest pressure scuba cylinders (at least in the US) are only rated at 3500 psi (241.3 bar), with the majority of high pressure cylinders rated at 3442 psi (237 bar).

In fact, the 3442 cylinders have neck sizes that will accept the 200 bar valves (and most come with them from the factory).

Some of the first yoke regulators to be rated to 3000 psi (207 bar) were the scubapro Mk5's with the weird barn shaped yoke. I would not use these on routinely on even standard 300 psi Al 80's. The later, more beefy yokes, are another story. These are certainly capable of being used on much higher pressures, and if you're ever in "cave country" you'll see these in use on tanks with 3400 - 3600 psi (234 - 248 bar) routinely.

Therefore, I would not hesitate to use a modern yoke regulator on a 232 bar valve in a 3442 psi (237 bar) tank. But that's just my opinion.

I didn't know about this stuff in the US. I thought the OP was trying to use his 300 bar cylinders with a 200bar yoke connection, hence the warning. I wouldn't start mixing up valves and cylinders. While there is no real danger in using a 200bar valve on a 300bar bottle, I consider it to be bad practice. There is a reason why there are different valves and connections. Mixing them up might lead to confusion and will make it more prone to accidents.

 

[DevonDiver]

Ok, I was confused because I misread that the OP was seemingly asking whether she could use a DIN insert to allow the use of a yoke reg on the 300 DIN tank valve.

I've just obtained two 300 Bar 7 L steel tanks, but one of my regs is yoke and the other is DIN. The tanks have got a 300 bar DIN valve each, and I've got a spare 232 bar valve, DIN with the yoke insert.

Will the 232 bar valve survive on my 300 bar tank? (until I convert that pesky first stage to DIN)

So, basically she is asking whether she can change the tank valve to the 200 DIN and use the adaptor with that for her yoke reg?

She could. But she shouldn't fill the tank to cylinder capacity. That said, would a dive operator even fill beyond 200, once they noticed the 200 DIN valve?

 

[Jimmer]

I think the big confusion is that the rest of the world has true 300 bar tanks, whereas in North America we dont have 300 bar tanks, but we do use 300 bar valves/regs. Over here, the max pressure of any common tanks is about 240 bar, so we just put whatever valve we want in it, and fill it to the pressure listed on the side of the tank.