o-ring durometer for Mares MR22

[Zef]

I am planning to purchase the parts needed to rebuild my Mares Abyss MR22 1st stage and have found seemingly good references for everything except the o-ring durometer. I suspect 90 as that is the usual recommendation for HP applications but I thought I read something a while back that mentioned 75 for these.

Is there a definitive consensus on durometer for the Mares 1st stage o-rings?

-z

 

[rsingler]

Can't believe no one has jumped in on this post. You're probably long done with your service, but my answer would be "some of both".
Duro 90 for o-rings that see high pressure air (both static and dynamic rings), and Duro 75 for orings that only see Interstage pressure.
There is an exception for orings that are well captured with fine tolerances between metal parts. You can use a Duro 75 here even at 3000 psi because they won't extrude due to the design of the lands. And the lower duro will often seal better.

Best way to guess is when you disassemble your Abyss, assuming it hasn't been too long since it was last serviced. With a little practice, you can tell which o-rings are softer (likely 70-75) and which are clearly D90's.

Cheers!

 

[rsingler]

Specifically, I'd recommend duro's as follows:
Duro 70-75:
OR 106 (PN 46110106)
OR 108 (PN 46110108)
Duro 90:
OR 2050 (PN 46110211)
OR 2012 (PN 46110101)
OR 2031 (PN 46110107)
OR 3043 (PN 46110247)

So technically, you were absolutely right. For this reg, just about everything that's not a port plug should be a Duro 90 oring, whether EPDM or Viton or nitrile.

Cheers!

 

[Scubagaskets]

Hi there all,

After the identification process that my consultant company ( europeseals) made for mares orings it concluded to the following results.
O-Ring Finder per Brand - Premium O-rings Provider for Scuba Diving

Hope this will be an assistace to you all.
Nicolas

Specifically, I'd recommend duro's as follows:
Duro 70-75:
OR 106 (PN 46110106)
OR 108 (PN 46110108)
Duro 90:
OR 2050 (PN 46110211)
OR 2012 (PN 46110101)
OR 2031 (PN 46110107)
OR 3043 (PN 46110247)

So technically, you were absolutely right. For this reg, just about everything that's not a port plug should be a Duro 90 oring, whether EPDM or Viton or nitrile.

Cheers!
View attachment 413151

 

[rsingler]

Hi there all,

After the identification process that my consultant company ( europeseals) made for mares orings it concluded to the following results.
O-Ring Finder per Brand - Premium O-rings Provider for Scuba Diving

Hope this will be an assistace to you all.
Nicolas

Sorry, but not sure I'd agree.
Your chart lists EVERY Abyss o-ring as SOFT, whatever that means. Duro 50? Duro 75? In my experience, the HP shaft o-ring for example (46110101) is Duro 90 for most every manufacturer. It's not captured, but only has the Teflon ring as a keeper. Soft o-rings will certainly seal, but I think dynamic ones will have an earlier failure, and the HP seat retainer o-ring (46110211) may extrude. Just my opinion, but if your company analyzed the Mares o-rings, I'd be interested in their estimate of Shore hardness instead of SOFT and HARD. But I could be wrong.

 

[Scubagaskets]

Dear Rsingler,
What i mean by Hard is Sh 90-/+ 5% and what i mean by soft is Sh 70-/+5%
What i can say is that Europeseals BV Holland came back to me with those results after all samples o-rings was given to them for identification of Sh,material and size using specialised equipment for that purpose.
Never the less at scuba gaskets we have Sh 70 and Sh 90 for nearly all of our NBR (nitrile) products and for some o-rings we have them in 5 different materials (EPDM,Black Viton for Nitrox, NBR,Polyurethane, and green viton for 100% oxygen)
Europeseals suggest that for all applications with gas pressure over 100bar the hard grade should be used (Sh 90) while both soft (Sh 70 ) and hard (Sh-90) can be used for pressures under 100bar. From my experience many of my customers find the soft grade (Sh70 ) more suitable for their needs in respect of easy installation and sealing properties regardless of the guidelines i provide them.
Kind regards
Nicolas