Dynamic O-ring Design
Dynamic O-ring Design
(OP)
I am trying to size o-rings for a piston in a cylinder. The cylinder ID is 12.8" +- 0.030". The OD of the cylinder, along with the width,depth, and type of gland are all design variables that I can control. I have room for two sets of o-rings, and plan to proceed with two o-rings. The piston will see a pressure that may range from 2000-6000 psig, and it is imperative that no air leak past the o-rings; however, the piston is dynamic and should be moved by the pressure (i.e., o-ring compression can not be terribly high). I plan on starting by selecting a nominal o-ring cross-section size that can be expected to provide a seal in these conditions, and then designing the gland and piston around that o-ring.
Can anyone suggest how I can go about initially gauging this size? Any equations or internet-based calculators? Any help would be greatly appreciated.
Thanks,
Haf
Can anyone suggest how I can go about initially gauging this size? Any equations or internet-based calculators? Any help would be greatly appreciated.
Thanks,
Haf





RE: Dynamic O-ring Design
RE: Dynamic O-ring Design
Thanks for the reply. I realize that +-0.03 is a lot of slop, but, unfortunately, I have to work with that. This system is being retrofitted with o-rings and was originally designed by someone else (o-ring design was not considered at the time).
What exactly is a polypack? Could you give me a few details? I am willing to consider any sealing option.
Thanks,
Haf
RE: Dynamic O-ring Design
Hugh
RE: Dynamic O-ring Design
http://www.parker.com/sg/parkerseals/valueadded.asp#appeng