Guide bushing

[surprise1968]

Hi
I am looking for material used for bushing guiding hot aluminium rod through.
1. Working temperature 400 C.
2.. Touch aluminum all the time but scratch on the surface of the rod is not allowed.
3. Antifriction.
I think some nonmetal materil would serve. (teflon,bakelite etc) But I am not familiar with.

Thanks

 

[arto]

Teflon wouldn't work @ that temperature - it melts above 500F/260C & breaks down & produces toxic fumes that cause "Fluoro-Polymer Fever" with "flu-like symptoms" - nasty! [they also warn not to smoke while handling teflon]

 

[sancat]

I would suggest graphite, which is both lubricant, and hot temperature proof; moreover, it is cheap.
In case that contact with the aluminum has to be avoided at all costs, you can use an air cushion, by the means of small holes on the graphite bushing, through which you could release hot (400C ?) compressed air.
sancat