What is a rail anchor used for, and how does it accomplish this purpose?
…and what railroad uses chrome-plated rail anchors?
Well, I’m sorry about the quality of the picture, but it was the only one that I could find. I’ve seen many of them along the ROW, and I even had a couple of them in my bedroom when I was a kid, but I’ve never really understood their purpose.
No problem, df, I wasn’t knocking your choice of photos- I just found it very amusing.
How about-When the rails aren’t tied up to a dock it keeps them from moving with the wind and the currents when the propeller is not turning?
Or: snapped on the rail tightly against tie it reduces (or eliminates?) the longitudinal movement of CW rail resulting from temperature changes. If the ties are properly ballasted, there will not be heat kinks. The lengthwise expansion and contraction of thirty-nine foot stick rail was delt with by the gaps at the rail joint.
…Yes, fights rail movement along it’s length due to forces outside the rail such as heat and cold and…train movements.
And how do they accomplish their purpose? They must come off fairly easy as I’ve seen enough of them laying on the ROW.
Actually that picture wasn’t chrome plate. It was Nickel Plate.
Aww, you beat me to it!
Anchors are fairly easily removed with a spike hammer, if you know where to tap 'em. In use they are attached to the rail and pressed snugly against the ties (wooden ties, anyway–I’m not sure what’s done with concrete). I wish Mudchicken were on line to help us out, but think he’s out east.
Part number 765?[:D]
Actually, they don’t come off easily at all, you have to give them a pretty good smack with a spike maul or sledge hammer to get them lose.
They clip on the foot of the rail, and force any expansion from heat upwards by keeping a slight compression on the foot or base of the rail.
Sorta like always having the base of the rail in a vise, slightly tightened…
MOW crew will often toss them when replacing rail that has been in place for a good while, the idea being that they have been in place so long they develop a memory of their own and no longer provide the correction compression.
Like reusing a 2 penny nail…you can, but why would you want to?
Rail anchors were used on jointed rail long before the advent of CWR to prevent the rails from moving as a result of the longitudinal force exerted by a passing train.
Mark
OK[bow]
I’ll accept that the ones that I have seen may have mostly been old ones from replaced rail. Then I can posit that the new ones that I saw were “extras” that were never installed to begin with.
But I am still baffled. How does attaching a rail anchor to the foot of the rail cause it to stop from expanding with heat? Doesn’t the rail anchor just expand too?
I will agree that rail anchors were used with 39 foot rail.
When you say that they were placed tightly against the tie to prevent longitudinal movement of the rail, wouldn’t that mean that there would have to be one on either side of the tie?
Not necessarily, but there are probably some standards for alternating the side of the tie where the anchor is installed. Consider: Depending on the weather temperature ranges at the location of the track, at the time of installation the rail is to have a temperature within a specified range. There is no problem with the shrinkage of the rail when the temperature drops below the installation point, but when it rises above that point, the linear expansion can cause a kink in the track. Not good. So if you start at about the midpoint of a length of CWR and put one only anchor on the oposite side of the tie from the nearest end of the rail, there will be the necessary physical constraint of the lengthening of the rail ue to a temperature above the installation temperature.
On the other hand I suspect that there a more frequent alternating from one side of the tie to the other to deal with linear movement of rail caused by trains.
Obviously, I only half know what I am talking about. I am sure the Mudchicken will come in soon with an accu
MUDCHICKEN!!!
Actually, Jay, you have done a good job of explaining, as have others.
But…
I still have another question. I have never seen rail anchors used with CWR, and I wonder if CWR would need them. After all, CWR doesn’t use spikes to fasten down the rail, but a different type of anchor on both sides of the rail. Wouldn’t that serve the same function as one of the J shaped anchors?
Also, you said that temperature drops are not a problem for CWR. I had read somewhere that CWR can break in extremely cold temperatures if it was too hot when it was laid. Yes? No?
I haven’t recently looked or paid that much attention to right up there state of the art rail installations so I can’t answer first question for sure. However, I am under the impression that tie plates and spikes are still generally used with wooden ties. On the other hand the rail fasteners use with concrete ties may indeed do the job of anchors.
Question two, you could be right. I really have no knowledge of the susceptability of a modern steel rail to breakage either due to “stretching” from cold or any increase to the brittleness. Somewhere I have read a bit about the matter of the temperature of the rail when it is installed, but I really have no idea how that optimum temperature is figured.
Notice just to the right of the weld being made on a section of CWR…see the tie plate and rail anchors, one on each side of the tie…
Anchors are made of a different type of steel than the rail, and with a different process, I think they are cold stamped instead of cast, so they expand at a slower rate then the rail.
There is a temperature window where welding rail is done, as you pointed out, if it is too hot when done, it can break when the temps get too cold, and the flip side, if welded when it is really cold outside, sun kinks will happen more easily.
Rail anchors dont not prevent rail expansion, they direct it, forcing it upwards instead of length ways.
…Seems we all strive to understand the installation and characteristics of especially CWR. It’s my understanding the laying of it to resurface a rail system ideally would be to do so in the mid range of ambient temp. the rail will be subjected to…{Summer and Winter}.
That way it has a middle working range of up in temp as well as down in temp as far as expansion and contraction is concerned. It is my understanding the rail anchors play an important part in retaining the rail in it’s “installed” position when heat or cold is applied by weather conditions.
And as Ed explained, they tend to force the expansion {and contraction}, up {or down}, as opposed to modfying it’s length.
The above just my opinion of understanding the process and reasoning.