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flat spots

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  • Member since
    October 2007
  • From: iron ridge
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flat spots
Posted by wisandsouthernkid on Friday, April 18, 2008 12:09 PM

how much of a problem are flat spots on wheels and can it make the wheel crack after a while or do they have to turn the wheel or if they are left can they stay in service because by my house i have heard so many flat spots on wheels it is not funny can it also hurt the rail.

 

One other question is chipped or peeling rail on turns bad or can it just be fine because alot of the rail that is over my my house on the curves the rail looks terrible the head is chipped and or pitted

the happiest people in the world dont have the best of everything, but make the best out of everything they have
  • Member since
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  • From: US
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Posted by csxengineer98 on Friday, April 18, 2008 1:26 PM

flat spots can be a major safty issue if they are too big.. they can hit the head of the rail hard enought to actuly brake the rail itself and possably cause a derailment.. as far as how they are delt with..being that im not mechanical other then changing out the wheels when a bad one is found.. i have no clue..but im sure someone else on here will give more detail to this subject...

now the rail question... no..it is not an issue.. totaly safe for train running..but you dont want to be playing with the flakes..they can be very shart and cut you worse then a razor blade...

csx engineer 

"I AM the higher source" Keep the wheels on steel
  • Member since
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Posted by Gary UK on Friday, April 18, 2008 2:59 PM
 wisandsouthernkid wrote:

how much of a problem are flat spots on wheels and can it make the wheel crack after a while or do they have to turn the wheel or if they are left can they stay in service because by my house i have heard so many flat spots on wheels it is not funny can it also hurt the rail.

 

One other question is chipped or peeling rail on turns bad or can it just be fine because alot of the rail that is over my my house on the curves the rail looks terrible the head is chipped and or pitted

Wheel flats do cause track damage depending on their severity as they inflict excessive forces to the rail. In the U.K on track staff like myself are required to report a vehicle or vehicles with excessive wheel flats. Indeed there are detectors on some main lines that will flag-up a badly flatted wheel. 

Rail damage that you describe can be RCF (rolling contact fatigue) or GCC (gauge corner cracking) GCC is normaly found on curves and looks abit like fish scales on the rail head near to the gauge face. If these go unchecked they can propergate into complete rail failure as demonstrated by the fatal Hatfield high speed derailment in the U.K a few years back. The rail shattered like glass under the train which was travelling at 110mph around a curve. It takes a trained eye to spot and diagnose GCC. RCF is similar but from what you describe sounds like 'spawling' of the rail head where part of the head shells away from the edge. Another problem is side cut rail on curves, this can include GCC but not always!! These defects can be cured by rail grinding and thats the purpose of rail grinding trains, you can grind out GCC before it gets severe enough that the rail has to be renewed.

It all depends on track speed wether or not the rail is dangerous, low speeds are less of a worry! If the track carries only freight at low speed, then the company will be reluctant to change it out in a hurry.

For abit of added interest i just uploaded a picture and good example of GCC. I took this on my cell phone while at work a few weeks back. After this was reported, it was ultrasonicly tested and changed a few days later.

This crack was right on top of a 'flash-butt' weld, also notice the shadow in the steel. Direction of trafic was from left to right.

 

  • Member since
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  • From: Mobile Alabama
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Posted by carknocker1 on Saturday, April 19, 2008 9:59 AM

Flat spots are caused by brakes not releasing , usually due to air brake failure , they are acceptable until the flat spot is not bigger than 2 1/2 inches . The wheels have to be changed out .

  • Member since
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Posted by Gary UK on Sunday, April 20, 2008 7:44 AM
More often than not, their caused by wheel slide due to in part by heavy braking and/or poor railhead conditions. Alot of vehicles nowadays can be fitted with wheel slide protection systems to eleviate the problem and associated damage that goes with it, kinda like a version of ABS.

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