HP80 Tank, 300bar DIN valve, yoke reg: questions about options for conversion (I'm a newbie)

[kkmcwhat]

Been diving steel 72's for about a year, and I like them, but rented an HP80 last weekend (I'm short, and the 72's either smack me in the head or in the legs), and it was awesome. I found a good deal on craigslist for one today, and brought it home, understanding that the valve was DIN, but thinking I could convert with an insert. Turns out it's a 300bar valve (I think; pictures below). My understanding is that an insert to convert to yoke isn't available for a 300bar DIN valve. First question: is this true?

Next questions: what are my options for using my yoke reg with this tank? (pics of tank and valve below too). I'm open to non-permanent adapters (as in, if I could still dive the 72s on a trip with my yoke reg, but there was a relatively easy adapter to use with 300bar DIN valve), or maybe preferably switching out the valve on the HP80 for a yoke valve. Somewhere I read that yoke valves don't go over 3000 psi - is this true? And if so... how did I dive one last weekend? I think I got in the water with 3400 on my pressure gauge; if that's the case, and I was using a yoke reg, there's gotta be a way to put a yoke valve on this tank, right?

Would love any help you guys could offer; I'd like to still dive all the tanks I have, and conversion to DIN in any kind of permanent sense isn't really something I'm interested in (all my diving is local, and I'm strictly interested in rec diving - no caves, no tech, not even really deep rec diving - so, DIN's not super interesting to me).

Any help is much appreciated!

 

[happy-diver]

Cut the front of the valve off

 

[kkmcwhat]

Cut the front of the valve off

View attachment 622191

HA. Now that's impressive.

 

[happy-diver]

It's not really, the insert is not screwed in so is proud of the valve which looks like it's been cut short
you can see the three raised lips where I slowed my motion with the angle grinder to check my line.

Still sitting somewhere in the collection of unfinished waiting department obstacles to peacefulness

Thanks!

and the cut is a bit off but ten minutes with a couple of files

 

[Storker]

Yokes aren't proofed for 300 bar, so any solution for joining a yoke reg to a 300 bar DIN valve will need some creative engineering. You won't find a suitable adapter in any store, because no-one is willing to take the financial responsibility of providing one.

US tanks aren't proofed for >240 bar, so I guess the simplest solution would be to switch the valve for a 200/232 bar DIN valve or a yoke valve. 232 bar DIN to yoke adapters are easily sourced, and with a yoke valve you won't have to worry about adapters. Alternatively, if your reg is approved for 300 bar, just switch the reg coupling to DIN.

 

[wnissen]

Yokes aren't proofed for 300 bar, so any solution for joining a yoke reg to a 300 bar DIN valve will need some creative engineering. You won't find a suitable adapter in any store, because no-one is willing to take the financial responsibility of providing one.

US tanks aren't proofed for >240 bar, so I guess the simplest solution would be to switch the valve for a 200/232 bar DIN valve or a yoke valve. 232 bar DIN to yoke adapters are easily sourced, and with a yoke valve you won't have to worry about adapters. Alternatively, if your reg is approved for 300 bar, just switch the reg coupling to DIN.

EDIT: I am wrong, see posts below.
Both your suggestions make a lot of sense to me. I have a DIN reg, I did buy the adapter to use yoke tanks, but have had to use it exactly once. Almost all tanks are convertible now. The DIN reg is so much more compact, to boot. But if you're not going to do that, switch the valve. You might find someone who wants to trade up to 300-bar DIN.

 

[-JD-]

The older 3500psi high pressure tanks use a 7/8"-14 unf thread that (almost) exclusively are 300bar DIN valves. Newer HP tanks (E7, E8, X7, X8, Faber FX) are 3442psi and use the "standard" (& physically larger) 3/4" thread valves, allowing for "pro-" or "convertable" valves.
Realistically, your choices are:
- Get/convert to DIN regs and use an adapter for yoke tanks
- Change to 3442 HP 80s with yoke-friendly valves
- machine your thermo valves to 230bar depth and have a locating dimple put on the rear.

 

[Scared Silly]

For the OP. Given what you have described (stay with yoke) your best option is to sell the cylinder because the only valve for that cylinder is not going to be usable with an insert. As said above by JD cylinders that have a 3500psi working pressure are 7/8"-14 unf thread with a 7 thread DIN valve. Where as the more common cylinder (3442 psi, 3000psi, 2400psi, etc) are 3/4" straight NPT and can use a 5 thread DIN valve with the doughnut insert (which is only 5 thread) for a yoke regulator.

Yokes aren't proofed for 300 bar, so any solution for joining a yoke reg to a 300 bar DIN valve will need some creative engineering. You won't find a suitable adapter in any store, because no-one is willing to take the financial responsibility of providing one.

This is really confusing to point of not making much sense. Not sure why you are using the term "proofed" as that relates to testing not design. Further, it has little to do with finance but functionality. The issue is that a yoke connection at higher pressure is not a reliable connection because the o-ring is not fully captured and can blow out. With a DIN connection the o-ring is fully captured and will not blow out.

US tanks aren't proofed for >240 bar, so I guess the simplest solution would be to switch the valve for a 200/232 bar DIN valve or a yoke valve. 232 bar DIN to yoke adapters are easily sourced, and with a yoke valve you won't have to worry about adapters. Alternatively, if your reg is approved for 300 bar, just switch the reg coupling to DIN.

Except as JD and I have noted the cylinder is a 3500 psi cylinder so the threads 7/8" so only a 7 thread 300 bar valve is going to work. Also most all modern regulators can be used with higher pressures such as 300 bar. Which the whole 200/300 bar nomenclature is a misnomer ...

 

[Storker]

I have a DIN reg

200/232 bar or 300 bar? I have a (300 bar) DIN reg, it fits any DIN tank valve. Granted, if I mount it to a 200/232 bar valve it'll have about two threads showing, but really, that doesn't make any practical difference.

A proper DIN reg will fit any valve rated for a pressure equal to or lower than its rated pressure. And it won't fit a valve rated for a pressure larger than its rated pressure. That's one of the many things I like with the DIN coupling.

 

[wnissen]

200/232 bar or 300 bar? I have a (300 bar) DIN reg, it fits any DIN tank valve. Granted, if I mount it to a 200/232 bar valve it'll have about two threads showing, but really, that doesn't make any practical difference.

A proper DIN reg will fit any valve rated for a pressure equal to or lower than its rated pressure. And it won't fit a valve rated for a pressure larger than its rated pressure. That's one of the many things I like with the DIN coupling.

You know, I never looked. It's 300 bar. The tank (HP 12L) valve is marked 0.750-14 NPSM so I guess that's a "200" bar valve.