Interferance Fit
Interferance Fit
(OP)
All,
Is a steel to steel Interferance Fit going to be water proof? I am not talking about any pressure, submerged in about 6" of water.
Regards,
Rich.....
Is a steel to steel Interferance Fit going to be water proof? I am not talking about any pressure, submerged in about 6" of water.
Regards,
Rich.....
Richard Nornhold, PE





RE: Interferance Fit
In general, the fit is not permanently (i.e. long time duration) water proof unless it is sealed.
Regards,
Cory
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RE: Interferance Fit
If it is a moving part you could do a mechanical seal. If not I would think about a weld bead or an O-ring.
RE: Interferance Fit
RE: Interferance Fit
Cheers
Greg Locock
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RE: Interferance Fit
Chocolates,men,coffee: are somethings liked better rich!!
(noticed in a coffee shop)
RE: Interferance Fit
Pressfit the parts then add Loctite 409. It will wick into the small crevices and seal the joint.
Ted
RE: Interferance Fit
Ted
RE: Interferance Fit
If you pressurise the O ring, typically by using several atmospheres of nitrogen behind it, then it will remain watertight so long as it remains pressurised.
Cheers
Greg Locock
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RE: Interferance Fit
Your leaking o-ring must have been a very special case with motion (this case is a press fit). I design vacuum equipment and I've never "rammed" an o-ring. O-rings will seal down to their permeability in a properly designed groove with less than 14 psi across them.
Timelord
RE: Interferance Fit
Fond as the MOD is of wasting money, I don't think this was one of the cases.
KENAT,
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RE: Interferance Fit
I was told that splashing and wave action were the hardest situation to seal, as the pressure varies locally on the seal the O ring rolls backwards and forwards imperceptibly, squeegeing water molecules through the seal. BTW this was for high end commercial sonar gear, not military.
Cheers
Greg Locock
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RE: Interferance Fit
Chris
"In this house, we obey the laws of thermodynamics." Homer Simpson
RE: Interferance Fit
RE: Interferance Fit
"In this house, we obey the laws of thermodynamics." Homer Simpson
RE: Interferance Fit
If you want to improve the sealing performance, why not put in a non-hardening self-forming gasket compound like Permatex 2.
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RE: Interferance Fit
The finish of my thought was: for a smooth cylindrical fit we can of course calculate the contact pressure. Wouldn't the joint behave similar to what you get if you cut the seam of the cylinder of contact and unreolled it into a flat bolted flange joint (with similar sealant) under the same contact pressure?
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RE: Interferance Fit
Thanks for all your input.....
Regards,
Rich....
Richard Nornhold, PE
http://www.ovenind.com