I am always walking along rarely used CN branchline during my lunch walk and I got a thought today. The inside of the rail is always worn more than the outside. Are these rails ever get replaced so that outside becomes the inside and vice-versa, to prolong the rail life?
It’s called “transposing the rail” and is done all the time, especially on curves (hi to lo, lo to hi).
When rail is too worn, then it is scrapped. If too small when replaced by bigger new rail, then it is “cascaded down” into yards and backtracks where it may serve for many decades and remove some even older/smaller rail to the scrap pile. Most rail in a yard started life on a main track somewhere.
I doubt it. The rail heads aren’t symetrical. If you reversed a rail, it would be angled the wrong way. I guess if there was enough rail head left you could grind it till it slanted the right way, but I can’t see that being as cost effective (or as safe) as replacing the rail.
LOL. OK, disregard what I said!
So when they transpose it, do they regrind it so that it’s canted at an opposite angle?
No, the cant is provided by the tie plates. Rail is symetrical.
???
On a branch line or shortline, you rarely see rail grinders.
On mountain main tracks, you try to transpose just before Speno or Loram get there with a big 108 stone grinder to remove the rollover, checks, pitting, shelling and all that bad stuff.
The side of the ball of the rail should be close to vertical (parallel)with main axis of the web. Why would you want to grind off perfectly good rail? Wheel flanges don’t rotate, why should the rail?
MC,
Does rail have a “life expectancy?”
I used to always check dates on rails wherever I went. I seem to recall a siding in Elburn, IL at the FS (that no longer exists) that predated the turn of the previous century…somewhere in the 1896 or so bracket.
Thanks in advance.
CopCar: Life is tonnage, environment and cycle based as is ties and bridges. (Timber ties are supposed to last 35 years)…Some curve rail on the Pueblo-Denver joint line only lasts 5 years. There is 1960’s 132# CWR in some long tangents just now coming out. There are places in little used backtracks where circa 1882 54# jointed rail is still in service. Las Vegas, NM and South Park Junction (Denver, south of Denver WW HQ) come to mind
(Contants aren’t, variables won’t story…[:D])
Old 39’ rail stick is/has been re-used a lot…
The first 3 feet on each end gets the most damage so they lob 3’ off each end making a 33’ section which is re-used.
Huh… 3 feet? I can see a few inches get more wear due to being close to the joint, but 3 feet is a lot!
It’s called joint batter and rail memory. (The rail around the end of the rail winds-up being permanently bent around the bolt holes. You cut it all out)
To add to dusty feathers post…
My switching lead is on a curve…about once every two or three years, we get it ground…every five to six, transpose.
This really depends on the traffic, as opposed to time in service.
The rail installed there today was new, put down in 1997.
It will last about one more grinding and transposing, then go to scrap because of the way it has worn and the memory it has developed…you cant straighten it out.
Bowl or yard track is a mix of several types of rail, from CWR to 39 foot section, ranging in age from pre WWII to current year, and in size from light to 115lb…We have compromise joints all over the place!
The switching lead gets hammered all day long by slow, heavy movements, so the inside of the curve wears faster.
It is in use about 22 hours out of 24, and with all the back and forth movement of a flat yard switch crew, it sees the worst you can do to track, sliding wheels, sideways stress, hard stops and lots of sanding.
On the main of a class 1 road, the wear would be a little more even due to elevation, but not a lot.
As mudchicken pointed out, just because it isn’t pretty perfect rail doesn’t mean it is bad rail, and now you know why you can see piles of “used” rail stored in yards…on hand repair inventory.
Ed
What about ligtht rail coming from a factory spur line, or seldom used siding
joining a heavy rail on the main line - There would be quite a difference in
the width and heigth of the rail - How is this compensated for ?
There are special rail joiners made for this. See “Compromise Joint” in the link below.
Wheel flanges don’t rotate? I thought they were part of the wheel?
Murphy : as in the wheel doesn’t “tilt”. If they don’t rotate about the axis of the axle (duh!), we can start talking about flat spots and slid-flat defects. Looking at the wheel/axle assembly in cross section, the wheels had better always be mounted at right angles to the axle.
Morseman: Step Joints (alias Compromise joints)
OK I get it now.[:I][D)] Thanks