Most common fluoropolymers used for hose in aircraft engines?

[LuisLazcano]

Hello, does anyone has an idea on which are the most common types of teflon or fluoropolymers used for hoses?

Specifically, I am trying to find out the materials used in a teflon hose application, that is part of the hydraulic system of a reverse thrust device, in an aircraft engine

Any hint is welcome. Thanks

 

[LuisLazcano]

Forgot to add that the only information I have from this hose, is that it´s made of a flexible material, with no additional coatings or covers, just the pure teflon (or a similar material). The hose transports an aircraft hydraulic fluid, not specified.

 

[patprimmer]

If you send a sample to DuPont, they should be able to tell you if it is PTFE or an injection mould-able Teflon which is reasonably similar to PTFE. There are many variations of the injection mould-able fluorocarbons.

My first guess would be that it is PTFE.

Some home grown tests in a simple laboratory are:-

Test specific gravity (you should confirm it, but I think from memory PTFE has an SG of 2.5)

Test for flammability. PTFE will not burn, but be careful as the degradation products are quite toxic.

PTFE will not melt. When heated sufficiently, it changes to a rubber like state.

If you can view it under a powerful microscope, you might see that it is not completely fused, but has some very fine porosity as the melt is so viscous, that even under tens of thousands of pounds per square inch, it does not force the powder to completely fuse.



Regards

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[Demon3]

Pure PTFE is white and goes semi-transparent when heated to around 220°C. As Pat said it can't be melted. Be careful though as DuPont use the Teflon tradename for at least three different fluoropolymers. The other Teflons are transparent, ead more at their website.

 

[plastx]

Check out Eaton at

http://aerospace.eaton.com/products/fluid_conveyance/hoses/index.html

They reference Teflon on this page which as previously mentioned can be several different fluoropolymers. I believe in this case it is a PTFE liner.