Rail noises upon train approach.

[Loop Line]

I wonder, are the noises made by the rails when a train is approaching caused by power in the third rail or the trains wheels? I assumed the wheels.

 

[AlterEgo]

Which sounds do you mean? Do you mean flange squeal, which is where train wheel flanges contact the side of the rail (on curves usually)?

Or do you mean the pulsing sounds that seem to emanate from the rails?

 

[fgwrich]

If it's a deep almost EE traction motor whine sort of noise (it's a difficult one to explain!) it may be down to recently ground Rails - usual noise after a visit from one of NRs Harsco, Speno or Loram railgrinders.

 

[Domh245]

The third rail is silent (or at least it doesn't make noise because of any current flow)

 

[randyrippley]

all rails vibrate as trains approach/pass and what you can hear are the rails rattling against the chairs / clips / sleepers, and also the bell-sound created by metal wheel on metal rail
you hear it less on jointed track as the gaps stop the vibrations propagating, on CWR the vibrations can carry for miles
only way to stop it would be rubber mounted rails, and even then the bell-sound would still carry

 

[snowball]

You can hear the sound of an an approaching train conducted through the rails even in areas where there is no third rail (and no overhead electrification either). It's the sound of the wheels on the rail and can be heard from a distance because steel is a good conductor of sound. It's more audible if the track is continuously welded.

 

[fgwrich]

The third rail is silent (or at least it doesn't make noise because of any current flow)

I would say it's almost silent - you can hear when the shoes go over a gap or the 3rd rails change sides though by the chink noise of the shoes sliding off one and hitting the other.

AC OHLE on the other hand does make a little bit of noice.

 

[samuelmorris]

I would say it's almost silent - you can hear when the shoes go over a gap or the 3rd rails change sides though by the chink noise of the shoes sliding off one and hitting the other.

AC OHLE on the other hand does make a little bit of noice.

See I find it the other way round - the point at which the shoes slide off the end of one rail and onto the next leave a clear gap when the noise of it sliding along said rail is absent, I'm not sure I can ever recall hearing the noise of a pantograph sliding along the wire, I'm sure it makes some noise but is always trumped by the rest of the noise the relevant unit makes.

 

[BR60062]

Its a great tool for getting the camera ready to photograph passing trains as you get into positiion to take the shot when the train shows up. It does make a very nice whooshing sound when its a fast train passing through .

 

[AnonymousUser1]

You can hear the sound of an an approaching train conducted through the rails even in areas where there is no third rail (and no overhead electrification either). It's the sound of the wheels on the rail and can be heard from a distance because steel is a good conductor of sound. It's more audible if the track is continuously welded.

yep that is my understanding as well , and it's amplitude / volume seem t obe dependent on the combination of mass / number of axles / wheels of the train

 

[Loop Line]

Thanks, I think it must be the wheels on the rails that I'm hearing. I had an inkling that it was but wanted to find out. On a similar note, I notice the mentioning of rails without expansion joints. Withut expansion joints, how do these rails allow for hot weather?

 

[ac6000cw]

Thanks, I think it must be the wheels on the rails that I'm hearing. I had an inkling that it was but wanted to find out. On a similar note, I notice the mentioning of rails without expansion joints. Withut expansion joints, how do these rails allow for hot weather?

See https://en.wikipedia.org/wiki/Track_(rail_transport)#Continuous_welded_rail