Engineering HSC Question. (1 Viewer)
- Thread starter molong
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mR sinister
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hmm, not to sure about the 'self lubricating bit',
but bearings in general, would be manufactured by powder metallurgy process since its a complex shape.
So i would first describe the powder metallurgy process, and then mention a suitable heat treatment process to improve it's strength ( as the bearing would be very weak and brittle after the powder process)
Maybe, just sum it up saying, it is coated with a lubricant?
Seems abit too much for 2 marks don't you think? but extra information wont hurt
but bearings in general, would be manufactured by powder metallurgy process since its a complex shape.
So i would first describe the powder metallurgy process, and then mention a suitable heat treatment process to improve it's strength ( as the bearing would be very weak and brittle after the powder process)
Maybe, just sum it up saying, it is coated with a lubricant?
Seems abit too much for 2 marks don't you think? but extra information wont hurt
we did this in the prelim course but i can't remember exactly what is was.
they're self lubricating because you DON'T need to coat them with lubricant and i'm pretty sure they are manufactured by powder metallurgy process.
i'll try find it in my notes and tell you when i do
they're self lubricating because you DON'T need to coat them with lubricant and i'm pretty sure they are manufactured by powder metallurgy process.
i'll try find it in my notes and tell you when i do
Self-lubricating bearings would be manufactured using powder metallurgy. This involves compressing two or more powders inside a die before heating until the powders fuse together. The bearings can then be heat treated or coated to produce desired properties. Powder metallurgy is used because the finished product is porous - ie. it has microscopic holes all through it. These holes provide a passageway for lubricative fluids (e.g. oil) to penetrate the bearing. Thus, the bearings only need to be applied with lubricant once in their lifetime because they act as a "sponge" of some sorts - they release lubricant when it runs out.
madsam
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Close, but no cigar
Self lubricating bearings are made by sintering (powder metallurgy process) with a slight twist
You get your powders for your bearing, and you add an small amount of organic material to the mix
you then compress the powders together and form your bearing
You apply heat, the powders bond and the organic material burns away
This leaves you with a porous bearing, which when dipped in a lubricant will absorb the lubricant
When the bearing is then placed in an inaccessible place, the oil keeps the surface lubricated and hence, self lubricating bearings
Self lubricating bearings are made by sintering (powder metallurgy process) with a slight twist
You get your powders for your bearing, and you add an small amount of organic material to the mix
you then compress the powders together and form your bearing
You apply heat, the powders bond and the organic material burns away
This leaves you with a porous bearing, which when dipped in a lubricant will absorb the lubricant
When the bearing is then placed in an inaccessible place, the oil keeps the surface lubricated and hence, self lubricating bearings