Threading for DIN and YOKE valves

[TheHuth]

I'm looking to buy some HP Steel 100 tanks. Surprisingly (to me anyways) every one I have found have been DIN. Is it possible to change the valve out for a yoke valve? I have several tanks I'm not using right now and would love to just yank out the valves and use them on some new HP Steels.

 

[oly5050user]

DIN more secure for hp use than yoke. O ring can extrude easily with yoke. With DIN o ring is captured cannot go anywhere

 

[TheHuth]

All of my regs are yoke. I'm looking at 3500 psi tanks, which isnt much more than a typical aluminum.

 

[oly5050user]

Should be able to convert. Hp tank typically filled to 3700 to3800 here. Yoke may work but taking chance on extruding.

 

[cool_hardware52]

All of my regs are yoke. I'm looking at 3500 psi tanks, which isnt much more than a typical aluminum.

3500 psi tanks are considered "High Pressure" and as such these tanks have 7/8 neck threads vs the 3/4 neck threads of common to tanks of 3442 psi or less. (As a side note the "7/8" threads in a true HP tank are smaller than the "3/4" threads found in most other tanks. The reason is they are different families of threads.)

Because yoke regs are not rated for use with High pressure (the concern is the yoke may fail) it's unlikely that you will find 7/8" threaded valves that accept yoke regs.

Personally I avoid 3500 psi tanks because the choice in manifolds is far more limited, and many 3500 psi tanks tend to be quite heavy.

If you really want to use 3500 psi tanks you need to transition to din regs.

Tobin

 

[Caveeagle]

Most tanks will have a 3/4" size valve. ( Low Pressure and Mid-pressure) There are some (less common) with a smaller valve thread, most people refer to as a Genesis style valve. (for some reason called a 7/8" even though its smaller)

So you can 'probably' change over your yoke valves if you want.

I would point out that many of the 'DIN' valves you see might actually be convertible "pro valves" that can accept a plug allowing you to use a Yoke Reg. These will be the shallower 200 Bar threads and will have a dimple on the back side of the valve to allow the Yoke screw to seat properly. Its pretty easy to tell from a pic just by looking for that dimple.

Only down side to the convertible "pro valves" is that the plug threads are exposed on the water side of the o-ring seal. So if your diving in salt water, you want to take extra care to rinse well, and maybe even remove the plug. Some might complain about the additional o-ring as an "additional point of failure". But the plugs DIN-side o-ring is much more robust than the Yoke-side, so its hardly the weakest link in the chain.

 

[tursiops]

I'm guessing the OP means a 3442 tank, not a 3500 tank. If he means 3442, then his yoke valves will fit. If he means 3500, then probably not.

 

[NAM001]

put one of these in and your problem as I understand it is solved

Scuba Valve Outlet DIN Plug Adapter G5 8 DIN Insert 8mm Hex Part DP13 1BP A | eBay

 

[cool_hardware52]

put one of these in and your problem as I understand it is solved

Scuba Valve Outlet DIN Plug Adapter G5 8 DIN Insert 8mm Hex Part DP13 1BP A | eBay

A din insert will not allow the use of a yoke valve on a HP only (3500 psi) din valve. The valve lacks the "dimple" for the yoke screw and should be too wide to allow the yoke to drop over the top of the valve.

Tobin

 

[TheHuth]

I just shot an email to this seller:

Scuba Tank - Steel 100 CF - High Pressure, Boot, Net, Cap

I figured I can look at it up close. Hopefully I can just use an adapter for the time being until I can convert over to DIN. And yes this is a 3442 psi tank. I know I've seen some that go to well over 4000 (I want to say 4750), so I can clearly understand the need for going DIN only at those pressures.