O-rings, O-rings

[brian cooper]

Hi all,

Did you know that with 38 different sizes of O-rings you have 98% of all regs covered, but then again we've been here before when I got accused of spamming for customers.

Oh by the way I now have all 38 sizes in Viton.....

Brian C

 

[Braunbehrens]

oxyhacker once bubbled...

And then there's always the chance that what you thought was a standard US size is actually a slightly different metric one.

It may not be a bad idea to put that in the legend of some of the more obvious regs (apeks?). Although almost all the o-rings in the apeks are static anyway, and the US ones seem to be a pretty good match. Maybe it's not such a big deal.

BTW here's what appears to be very useful O-ring source from one of the others lists. What's great about it is that they have 90 duro O-rings, which are often hard to find at reasonable prices, for not much more than the 70s. However, I haven't ordered from them yet. Note though that there viton is only 75, which many people feel is too soft (viton often not being as tough as nitrile) for general use, which is why dive suppliers usually supply only 90 viton as a replacement for 70 nitrile.

Interesting. I got a bunch of 90 duro vitons, so I guess I'll be using those. I bought them from allorings.com. I wasn't sure if it wouldn't affect the performance of the reg, using a harder O-ring than what was specified originally. I suppose in static applications it makes no difference anyway, it's the dynamic ones I'm concerned about, like the one around the rod that the HP seat is attached to.

 

[sexyscubadiver]

To answer the original question, new Scubapro o-rings are made of EPDM or ethylene-propelene, the ones before that were made of hyperthane, not the generic buna-n compound. Just thought you'd like to know.

 

[oxyhacker]

This thread got us thinking O-rings, so we threw together a quick-and-dirty size chart for some of the smaller metric O-rings, mostly the 1mm series, that have no equivilent in the AS586 series, and which reg manufacturers might - MIGHT - be using when they need a tiny O-ring. Or even if they aren't, might make a more reasonable substitute than trying to force in a 2-xx

http://www.airspeedpress.com/metric.pdf

The chart is in .pdf format. Download it then print it out. There's a size reference so you can check the scale and fine tune it as necessary. If you print it out on tracing paper or other transparent printable media you can use it as an overlay chart for cross referencing the O-rings shown in the ID charts in some reg manufacturers literature.

This is very much a work in progress, so any feedback is welcome.

 

[jeffkruse2000]

I just got my $70 worth of o-rings from air-oil. I got them the next day via UPS ground. Talk about fast service. I know where I am going for o-rings from now on!!!

 

[Braunbehrens]

oxyhacker once bubbled...

we threw together a quick-and-dirty size chart for some of the smaller metric O-rings

Aaargh, I hate trying to print stuff like this. I finally figured out that there is some buried print option in Acrobat to "shrink documents to fit on page", and disabled that. So now I'm getting 16 cm on the top...so far so good. Measuring along the side, I get just over 8.5 inches.

The weird thing is that if I measure the 1x10 O-ring I get exactly 1 cm diameter in each direction, and it looks perfectly round. Are you sure the side is 9"?

 

[Braunbehrens]

I have a couple of Apeks service kits, and they all say "not o2 clean" on them. I'm wondering, first of all, why the heck aren't they, and second, how should I clean them? After reading all the stuff on sintered filters not liking to be messed with, I'm kind of wondering what to do. The obvious would be to just do a simple detergent bath in warm water and rinse everything really well.

The sintered filters even have some dark areas on them, they don't look nice and new at all. Is it ok to put these into the ultrasonic acid bath?

Now it's got me thinking, when I throw a brand new viton O-ring in a reg, should I be degreasing it with detergent first?

Also, is there any reason not to use the ultasonic cleaner with detergent? I had one reg that I had to soak in liquid wrench to get it open, and I want to make sure I get rid of any oils that may be hiding inside some small passages inside the reg. body.

I know, a lot of questions...sorry.

 

[brian cooper]

You're right when you say Apeks kits are Oxygen compatible but not Oxygen cleaned. The manufacturer AND in this case Apeks cannot say for sure what someone else down the line is going to do with the bits before they install them in a reg for Oxygen/Nitrox use.
The end user could have greasy fingers, chicken fat has been mentioned for lubricating O-rings.....
The integrety of the packaging could have been breached...
When I Oxygen clean a reg/ pipework/pressure gauge etc I have to be able to say for sure that there is NO contaminant on or in the regulator and that it has been assembled using the correct quality of materials (O-rings,Gaskets,filters,and Lubricants) that have themselves been O2 cleaned and TESTED FOR OXYGEN SERVICE.

When a reg has been built up to this standard it is fully tested using double filtered air to Nitrox standards, and then double bagged and stored awaiting collection by the customer.
The packing is further examined in the site of the customer to ensure its integrity, if at fault I cannot state catagorically that that reg is still O2 clean.....

Parts should be cleaned, first in detergent solution to remove any greases(I use a citric based, non foaming,biodegradable,food grade detergent) in an ultrasonic cleaner then washed in warm distilled water, drained, then into HOT NEW UNUSED "acid" in the u/sonic cleaner. The parts are then drained,washed in warm distilled water and blown dry (again using double filtered low pressure air).
All parts are then tested for residual contamination using black ultraviolet light, specific for hydrocarbon/oil detection, and a transfer smear test.
They are finally examined under a stong light and 6X magnification for traces of lint and damage.
Only authorised lubricants are used and as little of that as possible to correctly lube the parts
Throughout all this work a clean work area is required,clean latex gloves, lint free wipes and clean (dedicated for Oxygen service) tools will be used.

Greasy/lint infested mucky thrown together in the back of a pick-up do not constitute an Oxygen clean...


thats my penneths worth

Brian C

 

[redacted]

Braunbehrens once bubbled...


Aaargh, I hate trying to print stuff like this. I finally figured out that there is some buried print option in Acrobat to "shrink documents to fit on page", and disabled that. So now I'm getting 16 cm on the top...so far so good. Measuring along the side, I get just over 8.5 inches.

The weird thing is that if I measure the 1x10 O-ring I get exactly 1 cm diameter in each direction, and it looks perfectly round. Are you sure the side is 9"?

Zeroed margins and zooming had no further effect.

By the way, anyone found a good match for the Scubapro S600 poppet stem o-rings (01050363 I think). Clearly nothing in the 2- but Parker bros show a 5-101 and 5-632 that look like good size candidates. I have not tried them yet as it looks like kits are still the best way to go. But it is always nice to know.

 

[Braunbehrens]

brian cooper once bubbled...


Parts should be cleaned, first in detergent solution to remove any greases(I use a citric based, non foaming,biodegradable,food grade detergent) in an ultrasonic cleaner then washed in warm distilled water, drained, then into HOT NEW UNUSED "acid" in the u/sonic cleaner. The parts are then drained,washed in warm distilled water and blown dry (again using double filtered low pressure air).
All parts are then tested for residual contamination using black ultraviolet light, specific for hydrocarbon/oil detection, and a transfer smear test.
They are finally examined under a stong light and 6X magnification for traces of lint and damage.
Only authorised lubricants are used and as little of that as possible to correctly lube the parts
Throughout all this work a clean work area is required,clean latex gloves, lint free wipes and clean (dedicated for Oxygen service) tools will be used.

Wow, that's quite a cleaning. I hope you are not suggesting that you are putting non-metal parts in the acid bath...

I think most dive shops don't go to the lengths you describe, and I personally would question if this is really necessary. The regulator is not likely to remain that clean for long anyway, and I haven't heard of the hundreds of oxygen explosions that would surely result if such a thorough cleaning really was necessary.

It certainly doesn't hurt to be this meticulous, but I haven't seen any dive shop tech go to these lengths.