Deflection/Stress from Compressed O-Ring
Deflection/Stress from Compressed O-Ring
(OP)
This may seem like a trivial problem, but I'm a new Engineer and the stress I am calculating from an O-Ring compressed roughly 30% seems a bit high, and am looking to see if I did this correct.
I have included the .pdf of my hand calculations
My stresses calculated are 16 ksi and 28 ksi, which is a significant difference...
Deflection is only 6/1000's this seems fair.
I have included the .pdf of my hand calculations
My stresses calculated are 16 ksi and 28 ksi, which is a significant difference...
Deflection is only 6/1000's this seems fair.





RE: Deflection/Stress from Compressed O-Ring
The O-Ring goes into the 0.070" gap. The O-Ring is 0.070" wide, and is compressed to 0.050"
RE: Deflection/Stress from Compressed O-Ring
RE: Deflection/Stress from Compressed O-Ring
RE: Deflection/Stress from Compressed O-Ring
But it shouldn't matter - you know you are getting 14 lbs. of force from the 30% deflection of the O-ring, and want to know what the probable normal stress is from the O-ring to the surface it is pressing on, correct?
Face-seal loaded oring. Oring o.d. = 0.441, i.d. = .301. Projected area = pi/4 *(.441^2 - .301^2) = .0816 in^2
Force = 14 lbs. (assuming you limit the deflection to 30%). Probable mean normal stress across contact area is
14 lbs./.0816 in^2 = 172 psi. If you want to argue that there is a Hertzian contact stress distribution, and the peak stress could be 2x of that value, I could say maybe.
But your numbers, if I interpreted your problem correctly, is high by about 2 orders of magnitude.
RE: Deflection/Stress from Compressed O-Ring