DIN to Yoke Adapter question

[nikolay_zhelev]

Hi guys,

I've purchased DIN to Yoke tank valve adapter, screw in type and I've noticed something unusual. As you can see in the attachment, there is flat screwdriver slot on the adapter inner ring providing access for o-ring replacement. It looks like it's manufactured with this slot.
Do you think this is something normal or it's a defect? I'm worried, because under 200 bar pressure this could be a serious failure point.

I'll appreciate your opinion

Please see the pictures below:

.

 

[guruboy]

Normal

 

[nikolay_zhelev]

Hi guruboy,

Thanks for your quick reply.

 

[Pkishino]

uhm, not normal according to the few inserts I have lying around. did a quick google and all the pics I found show a smooth round.. that looks like someone tried to use a flathead for removing the oring instead of a pick..

 

[nikolay_zhelev]

Hi Pkshino,

Thanks for your reply. Actually I found one picture showing same inner ring slot on wikipedia: Diving cylinder - Wikipedia under "Parts" section, but most of the pics on the network are with non-slotted adaptors.
However I beleive under pressure the o-ring will seal towards the outer wall, which makes me think that this slot wouldn't cause any leaks.

Feel free to comment my thoughts on the topic.

Have a safe dives guys!

 

[Pkishino]

Aha, like like you were right. Interesting, never seen one like that before. Well, either way, yes, it will seal via the oring. Thanks for posting that link

 

[tbone1004]

I have a few with, a few without. The o-ring is under pressure going outwards, so it won't cause any weird failure points, just makes it infinitely easier to get that o-ring out since they fail pretty regularly

 

[Scared Silly]

As said, some inserts and yoke valves will have a flat spot to facilitate removal of the o-ring. This image from the web link shows it quite well.

For clarity and knowing English is not the OP native language, this is a DIN to Yoke insert (rather than DIN to Yoke adaptor, below).

 

[Craig Lugo]

I just purchased a new insert because of this same thing. I thought the original owner of my cylinder had damaged the insert somehow. That was until I ran across an article on how air tends to get trapped behind the o-ring at depth. Then when you surface and remove your first stage the trapped air which has now expanded dislodges the o-ring and pops it out of the seat. It said that to help with this, some manufacturers started adding a special channel for the air to vent without dislodging the o-ring. I wonder if this is the remedy that they are speaking about.

 

[kelemvor]

All my din inserts have the flat part. I never thought anything of it since all mine happen to be the same.