On Friday, December 9, 2016 at 6:53:37 PM UTC-5, Jim Wilkins wrote:
"David Billington" wrote in message
news
On 09/12/16 22:22, Christopher Tidy wrote:
Thanks for all the useful answers. I'm looking for examples of
common products which are currently in production, and where a risk
of sudden failure exists if the bearing fails to behave properly.
Slow and lightly loaded applications aren't so interesting, as the
design isn't critical and the price is going to be the main factor.

Car engines and jet engines are interesting. The last small engine
I took apart (400 cc) had rolling element main bearings, whereas a
similar older engine (600 cc) had huge plain bearings and hardly
any signs of wear. I also saw a compressor with a ball bearing in
the big end of the connecting rod recently. This got me thinking. I
don't see so many plain bearings in modern products, or at least
nothing so visible as the bronze sleeves in my 1960s power hacksaw
and 1940s sewing machine. But maybe "see" is the important word.

Can anyone tell me what kinds of bearings are used in specific car
engines from well-known manufacturers today? Volkswagen, Ford,
Mercedes, etc.? An example or two would be useful

Thanks for the information.

Best wishes,

Chris
Chris,

I would guess that the small engine you took apart with rolling
element bearings was a 2 stroke, that's pretty standard whereas a 4
stroke would be plain bearing. Regarding compressors rolling element
bearings are simple and cheap and save having a pressure oil supply
and can be splash lubricated so may be used where they can be fitted
such as a single cylinder example a neighbour has or my 2 cylinder
with 2 bearings on a common pin. A mate used to work for Bendix air
compressors not many years ago and those compressors used plain
bearing and the oil supply was taken off the engine so no need for
an oil pump in the compressor. Another recent compressor I took
apart had ball bearings for the main bearings on the crank and the
big end bearings were plain supplied by a pick tube which dipped
into the oil sump. One of the items my mate mentioned about the
Bendix compressors was the conrods were aluminium and made from an
alloy formulated by Rolls Royce IIRC around WW2 so the material
properties suited the structural requirements of a conrod and acted
as a bearing material also as the rod material acted as the plain
bearing.

Honda runs camshafts directly in the aluminum of the cylinder head.

This was among the most thoroughly engineered, highest performance
mass-produced engines of all time:
http://www.connecticutscorsair.com/p...ne_history.htm
"..Pratt deviated from its former design philosophy of rolling-element
bearings and used plain silver-lead-indium bearings for the crankshaft
main and master rod bearings."

--jsw

Good article on the P&W 2800. Very good engine, but he neglected the engine analyzer distributor on the rear accessory gearbox in his listing of components there. That was only the later models though. Everyone has their favorite music, I reckon, but to an aircraft mechanic there's nothing more stirring than four 2800's running dry on a 40 degree day at full throttle when all 4 water/meth. switches are thrown. Man, they could sing when the juice hit.

Garrett

Garrett