Nylon bushing rpm

[Biiltit]

Will A nylon bushing, 3.75"od 2"id on a 2" shaft against identical nylon bushing at 10 lbs thrusting pressure at 5000 rpm, hold up or melt, deform from friction? If failure. Then how about changing one bushing to steel?

Please help

 

[plasgears]

DuPont gives good guidelines regarding the dynamic interaction of various plastics and plastic/metal interfaces.

The key is to not have similar materials interacting. Acetal-to-nylon is better that mating similar materials, for example.

 

[rnd2]

Biiltit
Sorry to be the bearer of bad tidings but unless you are planning to continuously liquid lubricate the bearing, nylon has no chance at 5000rpm. The surface will rapidly exceed the melt temp and drool away from the bearing surface. Even if it were lubricated, I would be sceptical about using nylon.
My company manufacures marine propeller shaft and pump sleeve bearings and at that speed, continuous water or oil lubrication is mandatory.

 

[Biiltit]

I think I will attach a oil embedded bronze washer to one Nylon hub and a steel for the other.

I appreciate all of your replies. Very helpful

 

[pierrig]

How about using a high temperature polyamide, like a polyphthalamide?
Their glass transition is about 110C and their melting point about 350C.

 

[patprimmer]

If you want high temperature nylons why not consider Stanyl nylon 4.6 which has a HDT of 295 deg C for some grades.

As already mentioned, nylon and acetal makes a very good bearing for plastics, and teflon plus silicon oil in the acetal makes it even better still, but negates the advantage of the high temperature nylons.

Without doing the sums, I doubt that plastics are suitable for this bearing.

Regards
pat pprimmer@acay.com.au
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