"Christopher Tidy" wrote in message
...
Hi folks,

I need an example for an article. Can anyone think of a modern product
which uses plain bearings in a demanding
application? I'm not talking about the extremes (like dental drills and
steam turbines), but more common applications such as supporting lathe
spindles and engine crankshafts. It used to be common to have plain
bearings in these machines, and some
were incredibly durable, but I haven't seen any in a new product for a
long time. Are there any examples, or have they been entirely displaced
by standardised ball and roller bearings?

What exactly is the definition of a "plain" bearing? Bronze bearings are
still used all the time in all kinds of things. They are great for fast
prototyping mechnical assemblies. Does a nylon bushing count? How about
acetal? How about teflon impregnated acetal? Is cast iron on cast iron in
a mill a plain bearing? Does it only count if its unlubricated? Do modern
exotic materials count?

With the range of materials available today I would be curious to know...

There are lots of simple mechaical devices that have a steel rod pushed
through a hole in a thermo plastic body. Is that a plain bearing? Or does
that not count because there is no third mechancial bit?

Is a plain bearings still a plain bearing if it "accidentally" operates like
an air bearing?