Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: sreering

Actually, the flat part of the wheel that rolls on the rail is not
really flat. It tapers gradually, being a slightly larger diameter
inbound near the flange and slightly narrower toward the outside. Since
the wheels and axle are one solid piece, this produces and active
steering that stops the wheel truck from 'hunting', which would result
in the flanges bouncing off one rail onto the other. If the truck drifts
to one side, the larger radius part of the surface on one wheel will
travel further for a certain angular rotation of the wheel-axle
combination than the smaller diameter part of the wheel on the other
side. This acts to turn the truck to bring the whole assembly back to
the center.

Nothing's ever simple :-)

Bob at PC

"John S. Denker" wrote:

On 11/21/2003 01:34 AM, Ludwik Kowalski wrote:
>
> A railroad car turns because rails turn. This can be
> viewed as a kind of steering. Potential energy would
> have to increase to derail such car.

Yes.


The thought about the railroad is apt and useful.
The wheel has a flange that is to a first approximation
cone-like ... I'm calling attention to the fact that
the wheel has a smaller diameter zone on the outboard
side and a larger-diameter zone (the flange) on the
inboard side.

| | | |
| | | |
|_ | | _|
R|_| |_|R (R = rail)
R R