To Din or not to Din?

[Jaydubya]

If you rent tanks you want a reg that matches what you rent. If you own your tanks it depends on your diving... IMO 200 bar din valves and 300 bar DIN regs are the way to go for tec and overhead diving even for 3500psi tanks. 300 bar valves will work but its harder to screw and unscrew the reg. Besides being less secure if there is an impact I've seen line tangled on yoke valvles.

 

[a_mart]

AMAZING WHAT I LEARN WHEN I READ THE MANUAL :s

"REGULATOR ATTACHMENT TO A TANK
WARNING: Maximum working pressure for an Oceanic Yoke style connec-
tor is 3500 PSI / 232 BAR and for a DIN style connector is 4500 PSI / 300
BAR"

I also looked at the service manual from 2005. The blow out drawing shows the two o-rings you mentioned Salty55150.
Bubbletruble, I like your idea of leaving one yoke and one Din now that I know DIN will be 300BAR. After looking at the Regs service manual i see it is easier to remove the yoke inserts from the K valves then it is to switch Din/yoke on the first stage. Either way I'll have a back up reg and get some practicle experiance with both connection types. As for oring troubles -I carry spares in my "save a dive" tool box along with 5/8, 11/16, and hex/alan wrenches, but I've not had o-ring/yoke troubles in my limited experiance.

 

[smellzlikefish]

Just to confuse the issue a little more, you could leave your regs yokes and get "pro" valves for your tanks. They have a yoke insert that screws into an otherwise DIN valve.

 

[drbill]

I have used DIN now for about 15 years. Greatly prefer it to yoke (although two of my spare tanks and both my pony bottles are yolk). I don't remember the last time I had to replace an o-ring.

 

[DMDavid]

Some of my tanks have the valve that drbill is referring to.

My SP regs can be converted from yoke to DIN in a matter of minutes.

My preference is the DIN valve but if you rent you will find that it is a good idea to have a yoke setup for rental tanks.


Posted from my iPhone using Tapatalk

 

[Bubbletrubble]

I have used DIN now for about 15 years. Greatly prefer it to yoke (although two of my spare tanks and both my pony bottles are yolk). I don't remember the last time I had to replace an o-ring.

This is because the external o-ring on a DIN-configured reg is replaced during a routine overhaul.
Some people get their regs overhauled every year or every other year.
I wonder how that compares to replacement of the external o-ring on a yoke tank valve.
Probably comparable.

On a related note, in-between dives, regs are generally stored in better temperature-controlled conditions than tanks are.

 

[Jaydubya]

Per dive, yoke o-rings get stressed about twice as much as DIN o-rings: once by the fill whip and once by the regulator. Even if they are the same quality (which has not been established) they are likely to fail about twice as often. The o-rings on tanks in a rental fleet are stressed way many more times and often more carelessly than they are on personal tanks. One would expect, from the frame of reference of the diver using rental tanks, that yoke o-rings leak or extrude far more often than DIN o-rings. This conforms to my observations.

 

[Bubbletrubble]

Per dive, yoke o-rings get stressed about twice as much as DIN o-rings: once by the fill whip and once by the regulator. Even if they are the same quality (which has not been established) they are likely to fail about twice as often. The o-rings on tanks in a rental fleet are stressed way many more times and often more carelessly than they are on personal tanks. One would expect, from the frame of reference of the diver using rental tanks, that yoke o-rings leak or extrude far more often than DIN o-rings. This conforms to my observations.

@Jaydubya: FWIW, in my experience, divers will only replace yoke tank o-rings when they fail at the dive site where little attention is paid to carefully cleaning the o-ring and the o-ring groove. When they do replace them, they use one of those pre-packaged save-a-dive kits which comes with crappy Buna-N duro 70 o-rings. There's no telling how old those o-rings are or what kind of conditions in which they have been stored.

Good point regarding the failure of yoke o-rings on rental tanks. I agree that, from the frame of reference of the diver renting yoke-configured tanks, those o-rings seem to extrude more often than the o-ring installed on a DIN reg.

To be fair, though, just because an o-ring is stressed twice as often does not necessarily guarantee a 200% failure rate.
I'm not an expert on o-ring manufacturing, but I'd like to think that a scuba o-ring in a static application can withstand several hundred (thousands?) relaxation-compression cycles.

 

[a_mart]

DMDavid - The K valve on my PST cylinder is setup the same way. When I buy more cylinders they will all have the same type of K valve.

Bubbletrubble - I have not had any oring issues with my current yoke setup but I also store all my dive gear in closet in my house - doesn't get colder then 50 degrees F nor hotter then 80 F.

My OW teacher made a point during class that it is a good idea to bring extra orings with you when diving because orings on yoke setups have been known to get lost or fail. I took his advice to heart and have always brought extra orings, silicon lube (I only dive air), and other on the spot simple repair supplies and tools .
As a side note my wife is currently taking her OW cert with the same instructor. I sat in on a few of the classes and made some observations. Most of the students rarely took notes even when the teacher explicitly said this question will be on the test and then proceeded to go over the answer. I will not be surprised if one day one of these students will complain about yoke orings and how they almost missed a dive because of them. I say almost missed a dive because usually I have seen other people on dive boats that bring their tool kits. The way some people take classes befudles me. I don't get it - they pay for an instructor and a book because supposedly they want the information but then fail to take notes or read the book. Sorry I went off on a tangent.

 

[a_mart]

@Jaydubya: they use one of those pre-packaged save-a-dive kits which comes with crappy Buna-N duro 70 o-rings. There's no telling how old those o-rings are or what kind of conditions in which they have been stored.

I may be guilty of this as I bought my orings at the dive shop with out thinking much about their quality. Do you have recomendations?