What is a rail anchor used for, and how does it accomplish this purpose?
Brian (IA) http://blhanel.rrpicturearchives.net.
blhanel wrote:...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.
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.
"We have met the enemy and he is us." Pogo Possum "We have met the anemone... and he is Russ." Bucky Katt "Prediction is very difficult, especially if it's about the future." Niels Bohr, Nobel laureate in physics
.....Yes, fights rail movement along it's length due to forces outside the rail such as heat and cold and....train movements.
Quentin
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.
Carl
Railroader Emeritus (practiced railroading for 46 years--and in 2010 I finally got it right!)
CAACSCOCOM--I don't want to behave improperly, so I just won't behave at all. (SM)
tpatrick wrote:Actually that picture wasn't chrome plate. It was Nickel Plate.
Part number 765?
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
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?
23 17 46 11
jeaton wrote: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.
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
KCSfan wrote: jeaton wrote: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. 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
edblysard wrote: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?
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?
Datafever wrote: KCSfan wrote: jeaton wrote: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. 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.MarkI 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?
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 accurate explaination.
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?
Datafever wrote: 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.
Ed, in your picture, I noticed that the rail is held in place by the use of both spikes and "rail hold downs" (those curvy shaped things). Do those things have a name?
I will accept that the use of rail anchors causes a redirection of expansion because of the compressive forces that it imposes on the rail, but I guess that I would like to understand the physics behind that a little bit better.
So, to sum up, rail anchors have two purposes. The redirect the expansion forces caused by heat on the rail away from the longitudinal, and they prevent the rail from moving longitudinally from train forces.
If your rails (jointed or CWR) are held down by cut spikes, you will have lots of anchors.
The type of rail anchor shown initially (plated) is a common channelock type.
If you have pandrols or D-E clips, the need for anchors are eliminated.
Anchors loose their grip with age and wear, thus the "pitched" anchors you saw. Some anchors can be slightly reformed and reapplied, but it is no longer cost effective.(costs more in energy and labor to recondition the anchor than to get new ones)
The application of anchors is totally dependent on the type of rail applicacation (cwr and jtd), where it is (curve/tangent) and that railroad's standard anchor pattern. Guaranteed you will find every tie anchored 250 feet in advance of switches and road crossings to hold gauge and to keep the rail from running in the switch. If an anchor is failing, it will slide and no longer remain snug up against the side of the tie.
Thank you, mudchicken.
I've noticed that when pandrols are used with concrete ties, they always have some type of (insulating?) substance between the pandrol and rail. Looks like a blob of plastic.
Data...
The lead you see in the photo has steel ties every third tie to hold gauge in the curve which is behind, or to the left of the weld...and there is a crossover to the right about ten feet past the weld, so rail anchors are on every single wood tie.
Last place in the world you want a car on the ground is in the middle of your switching lead crossover!
The pads are to prevent the harmonics and the vibration from the rail degrading the surface of the concrete tie...wood ties with fish plates can absorb the vibration as they sit.
Ed,
Let's see if I've got a handle on this now.
In your photo, there are steel ties to ensure gauge integrity. (Steel and concrete ties must, of necessity, use pandrols instead of spikes). In addition, the wooden ties all have rail anchors to prevent longitudinal movement of the rail, protecting the integrity of the crossover. And the plastic(?) that is used with concrete ties is to protect the integrity of the tie from vibration damage.
Got it. Thanks to all.
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