Are Poly-Flo Fittings Single Use?

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GESchwarz

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I'm just getting familiar with the Poly-Flo fitting and the Nylon tubing that mates to it. Apparently upon tightening the nut, the sleeve inside the nut permenantly compresses around the Nylon tubing.

Is there a way to remove tube from the sleeve without causing any damage tro the sleeve or tubing?

Can the sleeve that's inside the nut be reused once the Nylon tube has been removed?

It seems as though the ID of the sleeve is permenantly compressed when a tube is secured in the fitting.
 

Marc Zeitlin

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Dec 11, 2015
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Tehachapi, CA
I'm just getting familiar with the Poly-Flo fitting and the Nylon tubing that mates to it. Apparently upon tightening the nut, the sleeve inside the nut permenantly compresses around the Nylon tubing.
Yep.

Is there a way to remove tube from the sleeve without causing any damage tro the sleeve or tubing?
Nope.

Can the sleeve that's inside the nut be reused once the Nylon tube has been removed?
Nope. You can loosen the nut, remove the tube/olive assembly for maintenance, and then re-install/tighten it again, but if you remove the olive from the tube (or vice versa), you'll never get another tube through the olive once it's been compressed.

It seems as though the ID of the sleeve is permenantly compressed when a tube is secured in the fitting.
Yep.

Just more reasons to use more robust, more permanent tubing for brake lines, as mentioned previously.
 

rv7charlie

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You'll get varying opinions on these, but I've had good luck with push-to-connect style fittings for pitot & static lines. As long as the *outside* of the tube is in good shape, and you cut it square I've found that they seal well, and they're easy to repeatedly make/break the connections. They will typically work with the common plastic lines, and will work with aluminum too if you need it. (Don't use 'em for fuel...) They're available in just about any configuration, and multiple sizes. I wish I'd known about the 1/8" OD version (and 1/8" plastic tubing) before buying all my parts & plumbing the instrument panel. Would have made it a lot easier to fit everything in the limited space, using tighter bends in the tubing, etc.
 
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