Så kom den endelig.

[hannover_dk]

Jeg mangler også stadigt en rigtig god forklaring - både på en sub og en Orient ikke har helium valve.

Omvendt - måske Orient - ligesom IWC har konstrueret uret så det kan klare ikke bare et stort vandtryk udefra (WR) men også kan klare et stort tryk indefra (Helium)
Vi har tidligere haft refereret en tråd som her gengivet lidt

Citat:When IWC introduced its titanium Ocean 2000 in 1982 with WR of 2,000m, the Ocean 2000 actually exceeded easily the pressure ratings of Rolex SD (1,200m WR), Omega Ploprof (600m WR) and Seiko PD (600m WR). While IWC was officially claiming 2000m WR, Ocean 2000 watches were actually tested to 3,200m WR. The very same thing happened with GST Aquatimers introduced in 1997; officially rated as 2,000m WR, but actually tested to 3,200m WR.
Every dive watch is resistant to external overpressure (WR), but often forgotten fact is that IWC’s dive watches are also resistant to internal overpressure similar way as IWC’s Pilot watches. IWC’s with 200 bar WR can withstand internal case pressure at least 60 bar. Therefore, these IWCs don’t need helium escape valves, as they can withstand internal case pressure for maximum safe saturation diving depths. IWC also mentions that if a saturation diver worries about internal case overpressure, he or she needs to unscrew the internally threaded crown in order to release any build up of helium during the rather prolonged decompression cycle.

IWC could develop an extremely deep automatic diver that would break all existing automatic diver WR records, if IWC just wanted to. There’s no doubt about it. IWC does have the knowledge, technology and capability for that. Maybe IWC does it again…who knows, only time will tell…"

[url]"http://forums.watchuseek.com/showthread.php?p=1921953" onclick="window.open(this.href);return false;">http://forums.watchuseek.com/showthread.php?p=1921953[/url]

Helt enig i at en ting er at de skal kunne klare vandtrykket - som er vildt stort på 3.900 meter eller 2.000 meter - og så at de skal klare helium - som trænger ind over en lang periode i en tryktank - under tryk - og ikke kan nå at slippe ud hurtigt nok igen når tryk tanken letter trykket - og derfor - som det mere almindelige test scenarie - popper glasset af, med mindre man altså bygger som IWC - så de kan klare det store indvendige tryk på til 60 bar som er rigeligt i Helium sammenhæng (og så kan man jo løsne skrue kronen hvis man vil lukke Heilum ud i alle fald )

vh