What is the source and cause of that loud metal-on-metal squeaking sound as a rail car rolls by?

adofmsu@aol.com

the inside of the flange of the outside wheel in a curve rubbing against the inside of the outside ball of the rail! They try to add oil it tight spots.

JimLundquist55@yahoo.com

> the inside of the flange of the outside
> wheel in a curve rubbing against the inside
> of the outside ball of the rail! They try to
> add oil it tight spots.

Also, when a wheel set goes around a curve one of the wheels has to slide a bit. The two wheels turn at the same rate because they are connected by the solid axle. But, the distance traveled is different -- the outer rail through the curve than the inner rail.

Sometimes it is not oil but grease that gets placed on rails. It goes on the inside edge of the rail head -- NEVER on top.

Brian Norden

bnorden49@earthlink.net

axles to stop the inside rail from slipping along?

JimLundquist55@yahoo.com

about how much more complicated that would be. Each wheel on a separate axle that would have to be supported on each end, etc.


bnorden49@earthlink.net

why arent there any metal shavings left on the ground?

adofmsu@aol.com

> Also, when a wheel set goes around a curve
> one of the wheels has to slide a bit. The
> two wheels turn at the same rate because
> they are connected by the solid axle. But,
> the distance traveled is different -- the
> outer rail through the curve than the inner
> rail.

> Sometimes it is not oil but grease that gets
> placed on rails. It goes on the inside edge
> of the rail head -- NEVER on top.

> Brian Norden

The "sliding" is minimized, however, because railroad wheels are tapered, with the diameter near the flange somewhat larger than the diameter further away from the flange. There is some lateral movement as the wheelset goes around a curve. On a curve, the outside wheel contacts the rail at a point of larger wheel diameter than where the inside wheel contacts the rail. The outside and inside wheels rotate at the same rate, but the outside one covers more distance because of the larger diameter. I presume I'm "preaching to the choir" about this, but I just thought I would mention it.

-John

mcnamara@world.std.com

> The "sliding" is minimized,
> however, because railroad wheels are
> tapered, with the diameter near the flange
> somewhat larger than the diameter further
> away from the flange. There is some lateral
> movement as the wheelset goes around a
> curve. On a curve, the outside wheel
> contacts the rail at a point of larger wheel
> diameter than where the inside wheel
> contacts the rail. The outside and inside
> wheels rotate at the same rate, but the
> outside one covers more distance because of
> the larger diameter. I presume I'm
> "preaching to the choir" about
> this, but I just thought I would mention it.

I guess I had a bit of a senoir moment. Yes, the taper of the wheel tread does help. But the combination of taper, etc may not match and there will be wear (to rail or wheel or both) particularly on sharp curves. After the wheel moves all the way to the flange (biggest tread diameter) then you can get contact between the flange and the inside of the rail.

Brian Norden

bnorden49@earthlink.net

> why arent there any metal shavings left on
> the ground?

I've seen them, particularly through a switch. But they are fine.


bnorden49@earthlink.net

> axles to stop the inside rail from slipping
> along?

This has been tried. The tender from the WP's "GS-4" which is at Portola has this type of wheel and axle combination (wheels can rotate independently of each other on the axle). Axles with wheels not "permanenlty attached" are now "Remove on Sight" items, except for the talgo. This is what held up the tender's movement to Portola from Stockton for so long many years ago.

This is particularly noticeable on rusty rails as the wheel "pop" loose then slide with much fanfare (noise), but they will pop on well used rail in sharp curves as well.

> I guess I had a bit of a senoir moment. Yes,
> the taper of the wheel tread does help. But
> the combination of taper, etc may not match
> and there will be wear (to rail or wheel or
> both) particularly on sharp curves. After
> the wheel moves all the way to the flange
> (biggest tread diameter) then you can get
> contact between the flange and the inside of
> the rail.

> Brian Norden


Tennessee Valley Railroad Museum
newriver400@cs.com

Some time ago I put together a document on the action of railroad wheels on rail. I am not a rail professional nor do I have experience maintaining wheels or rail (nor am I sure all the concepts are correctly explained) but it might be of some use to railroad wheel laymen.

http://www.spikesys.com/Trains/whel_faq.html

Railroad Wheel FAQ
ebtrr@spikesys.com

> I've seen them, particularly through a
> switch. But they are fine.

And I've seen long "splinters" where the metal of the ball of the rail has been rolled under the head and split off. Mechanical rail flange lubricators are used on the Santa Cruz, Big Trees and Pacific in the San Lorenzo Canyon. On the Roaring Camp & Big Trees we use a small stream of water from the engine in front of the first wheel as a flange lubricant. It works well, is controllable from the cab, doesn't build up over time and is "eco-friendly"(water evaporates).

ironbartom@aol.com