I took NJTransit both to and from work today, as I often do. I only go a few towns away but both my trains seemed to be a little jumpy. I am talking about flat spots on the wheels. My train home not only had one serious one on my car, but when I watched it depart, which I always do anyway after all I am a train fanatic, I looked to see if I could notice anything. Sure enough, the car I was on was making a lot of noise, so was the car at the front, and the engine really pounded the ground as it went past. Seems like an epidemic. Now if I recall correctly, flat spots can actually cause a derailment in some instances, and I just seem to have noticed a few more lately. I also recall seeing a freight car you could actually see jump a bit when it turned. Anybody else experienced similar? Or is it true that it can cause a problem?
They do cause problems , they are usually caused by stuck Hand brakes or air brake problems . The FRA has set Guide lines for when the wheel becomes an issue .
§ 215.103 Defective wheel.
top
A railroad may not place or continue in service a car, if—
(a) A wheel flange on the car is worn to a thickness of 7/8 of an inch, or less, at a point 3/8 of an inch
Electronic Code of Federal Regulations: Page 7 of 34
http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid...7ec8008c2&rgn=div5&view=text… 9/9/2005
above the tread of the wheel;
(b) The height of a wheel flange on the car, from the tread to the top of the flange, is 1 1/2 inches, or
more;
(c) The thickness of a rim of a wheel on the car is 11/16 of an inch, or less;
(d) A wheel rim, flange, plate, or hub area on the car has a crack or break;
(e) A wheel on the car has a chip or gouge in the flange that is 1 1/2 inches in length and 1/2 inch in
width, or more;
(f) A wheel on the car has—
(1) A slid flat or shelled spot that is more than 2 1/2 inches in length; or
(2) Two adjoining flat or shelled spots each of which is more than two inches in length;
(g) A wheel on the car shows evidence of being loose such as oil seepage on the back hub or back
plate;
(h) A wheel on the car shows signs of having been overheated as evidenced by a r
A really bad flat spot can cause a rail to break, especially if the car is loaded.
Usually around this time of year you will notice an increase in the number of small flat spots on commuter trains. The reason is that falling leaves become extremely slippery when crushed under train wheels, similar to how slippery they are in the street (ever do a panic stop while driving on leaves? It’s almost as bad as snow). These slippery leaves cause the wheels to pick up when the train is stopping, thereby causing the flat spots.
Leaves seem to have a propensity for sticking to the top of wet rail, and they are, indeed, like grease. Our line runs through the woods, with grades approaching 1% in several areas. The wheel slip indicator gets a workout this time of year.