Hi all,
In hydraulic pumps and the like, you typically find o ring seals sitting in little grooves around a cylinder to prevent liquid leaks. Question is, are these grooves semi-circular or square in section? - if the o ring to go in it is circular section, that is.
cheers
Yes.
You're welcome.
They are normally rectangular (with a defined corner radius because you can never machine a perfectly square corner). Since rubber is incompressible (i.e. the total volume does not change when it is compressed, it squidges out somewhere else) you need to have room for any displaced material.
On flat flanges you sometimes have a "dovetail" groove to stop the ring from falling out (not a problem with grooves on a piston or a cylinder).
All the information you could possibly want is in here
Square, with radiused corners
Aha! Thanks, chaps. :)
Actually on reading the notes Newshound kindly pointed me to, I found this:
"The shape of the seal groove is unimportant as long as it results in proper compression of the seal between the bottom of the groove and the cylinder wall, and provides room for the compressed material to fl ow so that the seal is not solidly confined between metal surfaces."
Which makes life a bit easier! :)
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