Original Gas Escape Valve

[superlativechrono]

Floating around in the ocean one balmy evening this week (wearing a Sea-Dweller of course), I couldn’t help pondering the automatic gas escape valve.

Has anyone ever seen this in the “open” position?

I’d expect that the valve activates for a brief instant only (to equilibrate pressure) however, it’d be cool to see this in action either in the lab or real-world situations.

And yes, I know this is completely academic for nearly all of us who won’t take their watches to even 1% of their rated depth (let-alone into a He-mixed gas dive chamber) but still…..

[Andad]

I’m not sure how anyone could see this valve ‘open’ but it won’t be operating under water?

Iirc it requires a differential of about 45 psi.

[kieselguhr]

There are a handful of commercial divers on the forum (though many are long inactive). We’ll have to wait to for their response if they have ever seen it function. Maybe Padi has?

[csaltphoto]

Originally Posted by Andad

I’m not sure how anyone could see this valve ‘open’ but it won’t be operating under water?

Iirc it requires a differential of about 45 psi.

Yeah, the only place it would be opening is in the decompression chamber on the surface. The divers are living in an environment in which Helium has replaced varying amounts of the nitrogen in the air, and might have been doing so for weeks, as well as living at pressures anywhere from 5x atmospheric pressure to a lot more than that. During that time the Helium has seeped into the watch as well. Apparently human tissue can off-gas faster than a sealed up watch (Helium is a much smaller molecule than nitrogen). So during the gradual process of returning to surface pressure (which can still take days) the little HEV will gradually pop open to relieve the excess pressure. Also apparently, oxygen and nitrogen either don't penetrate the case or do so in small enough amounts not to require an HEV.

[77T]

Among professional divers working in saturation mode, you’d be surprised how seldom this comes up.


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[shaunylw]

Originally Posted by 77T

Among professional divers working in saturation mode, you’d be surprised how seldom this comes up.


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I like it though! It feels like the Rolex forum of the past with these type of discussions. Someone will ask about HEV values soon .

[Dirt]

It would be impossible to ever see it in the open position without some serious magnification.
The Helium molecules are so small and the amount of time it would need to be open wouldn't amount to a fleeting thought of a little burp with the small amount of Helium it would need to bleed off.

[padi56]

Originally Posted by superlativechrono

Floating around in the ocean one balmy evening this week (wearing a Sea-Dweller of course), I couldn’t help pondering the automatic gas escape valve.

Has anyone ever seen this in the “open” position?

I’d expect that the valve activates for a brief instant only (to equilibrate pressure) however, it’d be cool to see this in action either in the lab or real-world situations.

And yes, I know this is completely academic for nearly all of us who won’t take their watches to even 1% of their rated depth (let-alone into a He-mixed gas dive chamber) but still…..

Most all dive watches bought today will never see water other perhaps a shower, swim in the sea, or dip in the pool, and the max depth ratings on many of these watches will never be used by man or superman in water.The HEV is just a one way valve fully automatic on all the Rolex dive range it's only used for saturation divers who work underwater and reside at depth in dry chambers at the same outside water pressure.The gas they breath mainly now a high helium content the gas particles are that small they can pass thought the watch crystal seals etc.And when the divers are being re-compressed to normal atmosphere pressure, any gas thats in the watches escapes through the HEV valve as they return to normal surface pressure. Otherwise the gas would expand with the rise to normal atmospheric pressure, and the weakest point the crystal would most probably explode.A normal scuba diver would have no need to use the HEV on any watch.Think of it this way take a balloon down to 10m under water. That's 2 atmospheres one water pressure one surface air pressure.Now fill that balloon with air at that pressure of 2 atmospheres.Now because the compressed air is now under-pressure and quite dense. You can fill it but the amount of air breathing gas content would be twice as much as normal above water on the surface.Now release that balloon and let it go back to the surface because of the return to one atmosphere surface pressure balloon would expand and burst simply because there was twice as much air in it at surface pressure.

[padi56]

Originally Posted by kieselguhr

There are a handful of commercial divers on the forum (though many are long inactive). We’ll have to wait to for their response if they have ever seen it function. Maybe Padi has?

Been in a recompression chamber a few times with my 16600 SD after breathing high Helium gas mix but that was many many years ago but never watched it to see if it moved but it would be a blink of your eye quick. And talking about the the HEV it was around 1969 when Doxa introduced the first divers watch equipped with a Helium Release Valve, that was available first to the general public.And its widely believed to have been co-developed by Doxa and Rolex at that time.Now Rolex submitted a prototype patent on 6th November 1967, its thought only around 50 of these double Red 1665s were distributed with patent pending backs.Although Rolex fitted Submariners (model 5513 - non date) with prototypes of this escape valve, for the COMEX divers.They did not start to build the Helium Release Valve into their retail dive watches until the SD in 1971,two years after the Doxa. Now after a bit of negotiations with Doxa and both companies had a very good working relationship at that time.So its widely believed they decided to share the HEV Valve patent,just to get it into production and for sale to the public the new HEV Rolex SD.

[MrGoat]

Originally Posted by padi56

Been in a recompression chamber a few times with my 16600 SD after breathing high Helium gas mix but that was many many years ago but never watched it to see if it moved but it would be a blink of your eye quick. And talking about the the HEV it was around 1969 when Doxa introduced the first divers watch equipped with a Helium Release Valve, that was available first to the general public.And its widely believed to have been co-developed by Doxa and Rolex at that time.Now Rolex submitted a prototype patent on 6th November 1967, its thought only around 50 of these double Red 1665s were distributed with patent pending backs.Although Rolex fitted Submariners (model 5513 - non date) with prototypes of this escape valve, for the COMEX divers.They did not start to build the Helium Release Valve into their retail dive watches until the SD in 1971,two years after the Doxa. Now after a bit of negotiations with Doxa and both companies had a very good working relationship at that time.So its widely believed they decided to share the HEV Valve patent,just to get it into production and for sale to the public the new HEV Rolex SD.

Thanks for sharing your abundance of knowledge with us Peter!!


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[brandrea]

Originally Posted by padi56

Been in a recompression chamber a few times with my 16600 SD after breathing high Helium gas mix but that was many many years ago but never watched it to see if it moved but it would be a blink of your eye quick. And talking about the the HEV it was around 1969 when Doxa introduced the first divers watch equipped with a Helium Release Valve, that was available first to the general public.And its widely believed to have been co-developed by Doxa and Rolex at that time.Now Rolex submitted a prototype patent on 6th November 1967, its thought only around 50 of these double Red 1665s were distributed with patent pending backs.Although Rolex fitted Submariners (model 5513 - non date) with prototypes of this escape valve, for the COMEX divers.They did not start to build the Helium Release Valve into their retail dive watches until the SD in 1971,two years after the Doxa. Now after a bit of negotiations with Doxa and both companies had a very good working relationship at that time.So its widely believed they decided to share the HEV Valve patent,just to get it into production and for sale to the public the new HEV Rolex SD.

I always appreciate the history lessons Peter. It’s one of the reasons I joined here. Thank you and happy new year to you and yours

[padi56]

Originally Posted by MrGoat

Thanks for sharing your abundance of knowledge with us Peter!!


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Originally Posted by brandrea

I always appreciate the history lessons Peter. It’s one of the reasons I joined here. Thank you and happy new year to you and yours

Only glad to pass on a bit of knowledge and information Brian and Mr Goat, and all supplied from my own 79 year old brain power, that I have taken the trouble to learn about Rolex/Tudor over the past 50 odd years. But today its nicknames, alignment points, protective watch film, AD relationship building spending, investment ££$$$€€€€ stuff, special cleaning cloths, phone apps, and the rest of todays Rolex watch toys that now takes priority on forum over any Rolex/Tudor knowledge.

[ratty]

Originally Posted by padi56

....
The HEV is just a one way valve fully automatic on all the Rolex dive range it's only used for saturation divers who work underwater and reside at depth in dry chambers at the same outside water pressure.The gas they breath mainly now a high helium content the gas particles are that small they can pass thought the watch crystal seals etc.And when the divers are being re-compressed to normal atmosphere pressure, any gas thats in the watches escapes through the HEV valve as they return to normal surface pressure. Otherwise the gas would expand with the rise to normal atmospheric pressure, and the weakest point the crystal would most probably explode.

If the helium particles they can pass through the crystal, seal etc. to get in, why can’t they get out the same way?

Presumably this is because of the differences in the time the watch is subject to the different pressures? Typically do divers stay in the high pressure / helium concentration environment for a lot longer than the time needed for safe decompression? Does it take longer for the helium to get in than it does to decompress?

You can, no doubt, tell that my diving experience is non existent!

Thanks in advance.

[Gerry62]

Originally Posted by padi56

Only glad to pass on a bit of knowledge and information Brian and Mr Goat, and all supplied from my own 79 year old brain power, that I have taken the trouble to learn about Rolex/Tudor over the past 50 odd years. But today its nicknames, alignment points, protective watch film, AD relationship building spending, investment ££$$$€€€€ stuff, special cleaning cloths, phone apps, and the rest of todays Rolex watch toys that now takes priority on forum over any Rolex/Tudor knowledge.

Your interventions are breaths of fresh air. Thanks, reading you is essential ... necessary

[padi56]

Originally Posted by Gerry62

Your interventions are breaths of fresh air. Thanks, reading you is essential ... necessary

Thanks much appreciated.

[inadeje]

Originally Posted by padi56

Most all dive watches bought today will never see water other perhaps a shower, swim in the sea, or dip in the pool, and the max depth ratings on many of these watches will never be used by man or superman in water.The HEV is just a one way valve fully automatic on all the Rolex dive range it's only used for saturation divers who work underwater and reside at depth in dry chambers at the same outside water pressure.The gas they breath mainly now a high helium content the gas particles are that small they can pass thought the watch crystal seals etc.And when the divers are being re-compressed to normal atmosphere pressure, any gas thats in the watches escapes through the HEV valve as they return to normal surface pressure. Otherwise the gas would expand with the rise to normal atmospheric pressure, and the weakest point the crystal would most probably explode.A normal scuba diver would have no need to use the HEV on any watch.Think of it this way take a balloon down to 10m under water. That's 2 atmospheres one water pressure one surface air pressure.Now fill that balloon with air at that pressure of 2 atmospheres.Now because the compressed air is now under-pressure and quite dense. You can fill it but the amount of air breathing gas content would be twice as much as normal above water on the surface.Now release that balloon and let it go back to the surface because of the return to one atmosphere surface pressure balloon would expand and burst simply because there was twice as much air in it at surface pressure.

Thank you for that clear explanation. Very informative as always.

[Dirt]

Originally Posted by ratty

If the helium particles they can pass through the crystal, seal etc. to get in, why can’t they get out the same way?

Presumably this is because of the differences in the time the watch is subject to the different pressures? Typically do divers stay in the high pressure / helium concentration environment for a lot longer than the time needed for safe decompression? Does it take longer for the helium to get in than it does to decompress?

You can, no doubt, tell that my diving experience is non existent!

Thanks in advance.

Your assumption is basically correct.
The exposure time in the Helium environment is many times longer than the duration of decompression.
It gets in slowly, but can't get out quick enough without the valve facilitating it thus preventing the Crystal from popping off.

[Greenwood_]

Originally Posted by padi56

Most all dive watches bought today will never see water other perhaps a shower, swim in the sea, or dip in the pool, and the max depth ratings on many of these watches will never be used by man or superman in water.The HEV is just a one way valve fully automatic on all the Rolex dive range it's only used for saturation divers who work underwater and reside at depth in dry chambers at the same outside water pressure.The gas they breath mainly now a high helium content the gas particles are that small they can pass thought the watch crystal seals etc.And when the divers are being re-compressed to normal atmosphere pressure, any gas thats in the watches escapes through the HEV valve as they return to normal surface pressure. Otherwise the gas would expand with the rise to normal atmospheric pressure, and the weakest point the crystal would most probably explode.A normal scuba diver would have no need to use the HEV on any watch.Think of it this way take a balloon down to 10m under water. That's 2 atmospheres one water pressure one surface air pressure.Now fill that balloon with air at that pressure of 2 atmospheres.Now because the compressed air is now under-pressure and quite dense. You can fill it but the amount of air breathing gas content would be twice as much as normal above water on the surface.Now release that balloon and let it go back to the surface because of the return to one atmosphere surface pressure balloon would expand and burst simply because there was twice as much air in it at surface pressure.

Thanks Padi - enjoy reading about the pioneering Rolex and other watch brands supported through their R&D!

I tried on a DSSD for the first time just yesterday, it’s heft instills a fair bit of confidence!

[tudk]

Originally Posted by padi56

Thanks much appreciated.

I have a JC
Thanks mate for the informative explanation.

[ratty]

Originally Posted by Dirt

Your assumption is basically correct.
The exposure time in the Helium environment is many times longer than the duration of decompression.
It gets in slowly, but can't get out quick enough without the valve facilitating it thus preventing the Crystal from popping off.

Thanks.

[padi56]

Originally Posted by Dirt

Your assumption is basically correct.
The exposure time in the Helium environment is many times longer than the duration of decompression.
It gets in slowly, but can't get out quick enough without the valve facilitating it thus preventing the Crystal from popping off.

Quite true it all depends on how long the divers have been working at the water pressure depth, it could take a week or longer before they are very slowly returned to normal surface pressure in the sealed pressurised living quarters chamber.

[superlativechrono]

Great responses and discussion folks - thanks!

[KeithP]

Such great stuff. Thank you as always, Padi.

[csaltphoto]

And who knows if the valve is designed to just let helium out or to better equalize the air pressure. Basically "burping" the watch. Rolexes are designed around positive pressure gradients (water pushing from the outside) not negative pressure gradients (air pushing from the inside). A saturation diver might be operating at anything from 5 times normal atmospheric pressure (~ 160 ft/50 meters) to a LOT more. Some of the older COMEX divers were working at 50+ atm.

Rolexes are basically 1 atm submersible's.

[SeaDweller50]

Whilst on the subject of saturation diving, have you seen the following documentary on Netflix. An absolute must watch.

https://en.wikipedia.org/wiki/Last_Breath_(2019_film)

[kieselguhr]

Originally Posted by SeaDweller50

Whilst on the subject of saturation diving, have you seen the following documentary on Netflix. An absolute must watch.

https://en.wikipedia.org/wiki/Last_Breath_(2019_film)

Great documentary.

The scene of Dave hauling a “thing” that needed to be taken from one place to another was awe inducing.

I cannot begin to comprehend the tremendous effort and strength needed to do what that man did. Mobility in a dry suit alone is severely impaired, that compounded by water pressure, weight of gear... unreal.

[SpiritSoul]

Check the following video out to get an idea of the mechanics in theoretical action:
https://youtu.be/SPvtXaI7dYQ

and the following article:
https://millenarywatches.com/rolex-helium-escape-valve/