Railroad tracks. 140 lb. rail?

Question

when rail is 140 lb rail what does that mean? does it mean 1 foot or 3 foot rail is a 140 lb rail? not sure what it means?

Answer 1

Rail is measured by pounds per yard.  140 lb. rail is some pretty heavy-duty mainline rail, use in places with heavy traffic such as yard throats, etc.  132 pound rail is the standard for mainline track.

Answer 2

It is an old old standard.

Different rail needs use different rails wieghts and it is in pounds per yard.

Standard rail length for years and years before CWR (continuous welded rail) was 13 yards or 39 feet. That was developed because of the 40 foot flat cars that were railroad standard for most of the railroad industry until after WWII.

Heavy traffic naturally needs heavier rail to stand up the the stress, I remember not so long ago, (since thelast ice age anyway) when 115 was pretty darn good rail, now it isnt even used in sidings very often, branch lines or yard tracks is all.

If you look on the flat part or "web" of a rail you will see numbers, one of them is the weight and the manufacturer and usually the year.

It is not unusual to find rail in old yards or branch lines that is close to a hundred years old and it still uses the exact same method of identification.

Answer 3

Well its the weight of the rail per 3' the high speed "good rail" is thick and strong about 47lb a foot but the cheaper rail that isnt meant to be used every day is lighter helps to save on cost

Answer 4

That's it. Not sure how many pounds per how many inches. Of course it would be centimeters in those other countries that use the metric system. The actual rail is measured in "gauge".  There is a standard gauge in the US and most european countries. Eventually there will probably be a standard gauge worldwide. I know we have trains that can run from the US to South America on the same gauge or rails.

Good Luck!

Answer 5

redsox,

Indeed, a rail's weight is determined per yard, such as  90 lb, 110 lb, 125 lb, 140 lb, etc.  Most of the stuff used on the heavy main lines today is at least 120 pounds with lighter rail used on secondary and branch lines.

Regarding gauge, this is simply the width between the rails which is 4 feet 8 1/2 inches (Standard gauge), here in the U.S.

Answer 6

The pound rating is pounds per yard. 140 pounds is pretty hefty. The Transcontinental Roalroad completed in 1869 was built with 45 pound rail. The maximum load that a steel rail can support (with properly spaced ties) is 300 pounds per wheel for each pound weight of rail per yard. In other words, the Transcontinental RR could safely carry 300 x 45 pounds per wheel. Or, 13,500 pounds per wheel, which is 27,000 pounds per axle (13.5 tons).  As trains got heavier, so did the rail. By 1880, the normal mainline rail weight was 56 pounds. By 1910, it was 90 pounds.