O-Ring groove design
O-Ring groove design
(OP)
Hi,
I want to get knowledge on O-ring groove design.
Can anyone help me in how to decide on particular O-Ring? which table and how it to be used.
Thanks
I want to get knowledge on O-ring groove design.
Can anyone help me in how to decide on particular O-Ring? which table and how it to be used.
Thanks





RE: O-Ring groove design
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: O-Ring groove design
RE: O-Ring groove design
Parker is an excellent company and fully supports design applications. They had an elastomer program called INPHORM which I believe is still available. Get both the o-ring and polypak editions!
And when it comes to rubber, these guys are the best. I highly recommend earmarking their website. And no, I am not a Parker employee or salesman, but definitely a disciple of that business.
Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada
RE: O-Ring groove design
Use the Parker handbook.
Do not deviate from it.
The designs encoded therein are already optimized.
Mike Halloran
Pembroke Pines, FL, USA
RE: O-Ring groove design
Isn't always more fun to go off rapidly on your own and invent your very own personal mistakes rather than look up and actually study somebody else's stuffy reference book ... just because they've been doing it for years? 8<)
RE: O-Ring groove design
Mistakes usually come from departure of receipe values offered by the various manufacturers. I have bastardized several gland specifications based on design problems, so have a very accurate set of equations that govern stretch (known as set) and squeeze (also known as compression). I would recommend the study of these two issues, they govern the reason as to why elastomers perform. Gland geometry is set by "fill".
Also note that there are multiple applications that specify gland depth defined from the seal diameter. The application being static, dynamic, reciprocating or face seal are the four main categories you need consider.
And don't forget the rubber compound, chemistry, explosive decompression, set and degragation given lifetime are important considerations.
Good luck with it.
Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada
RE: O-Ring groove design
RE: O-Ring groove design
RE: O-Ring groove design
While I make every attempt at using standard o-ring sizes and gland designs, in reality all the o-ring manufactures produce far more sizes. In particular, the AS-568 series is seriously lacking for small cross section o-rings. How on earth did they think that only 4 sizes were needed with a cross section smaller than 1.78mm? We use 20 different sizes with cross sections smaller than 1.78mm and we are pretty small.
Proper material selection is key to successful o-ring applications. There are an almost infinite number of compounds, Precix has at least 40 standard fluorocarbon compounds and quite a few more specialized ones. Learn how to use the ASTM D2000 / SAE J200 specification for rubber compounds and run as fast as you can from any supplier who can't quote it chapter and verse.
Beware of stockist who say they have "viton" o-rings. Usually this means there is no pedigree and no traceability on these o-rings and they are almost always made in a "low cost country" with a lot of filler and very little fluorocarbon, almost certainly NOT from an actual DuPont Viton(R) compound.
All that said, if you can avoid or eliminate an o-ring it will improve your design reliability and reduce your design FMEA RPN.
RE: O-Ring groove design
RE: O-Ring groove design
RE: O-Ring groove design
RE: O-Ring groove design
RE: O-Ring groove design
In my experience, radial o-ring connections are a very reliable method of producing a non-permanent pressurized connection. I've always felt them superior to compression fittings in dynamic applications; it is often easier to provide secondary retention to the threads in an o-ring connection. What were you thinking of as an alternative?
------------------------------------------------------------
I agree o-rings are good for a non-permanent connection. I was thinking more of permanent installations. I have been doing fuel devices for 25 years and everything for the last 12 years or so has been 100% laser welded. Much lower defect rates. No cut, twisted or missing o-rings. No leaks due to scratches or bad surface finish.