Talk:Rail tracks

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[edit] Exclusive UK Usage is Gibberish to North Americans

This article is utterly incomprehensible to a North American reader -- Unless one is from the UK, the word "sleeper" refers to a Pullman sleeping car. A mere paranthetical explanation of this or that term is insufficient -- there are so many that the entire article might as well be in Swedish. It's current "B" rating is overly generous.

I suggest that two separate articles be maintained, one in each dialect.Scott Adler 00:34, 12 March 2007 (UTC)

Good heavens! What an unusually belligerent observation. As a North American reader who had no difficulty getting used to the sleeper/tie nomenclature, I'm inclined to disagree with you. If you feel absolutely certain that an improvement is warranted, maybe you should give it a shot. Geoff NoNick 01:18, 13 March 2007 (UTC)

The fact that the author has even bothered to include for Americans is to his credit. Personally I wouldn't have bothered. How could it be that the master race cannot read a simple dialogue in UK English? English people appear to have no problem interpreting incorrect use of the English language by Americans. —Preceding unsigned comment added by 165.228.109.98 (talk) 02:22, 20 March 2008 (UTC)

[edit] Feste Fahrbahn?

Is there an english term for the German Feste Fahrbahn? Something like "solid track" perhaps? [1] shows tracks on the German Cologne-to-Frankfurt line (300 km/h) which was built without any track ballast. --Qualle (talk) 07:18, 21 April 2006 (UTC)

Babelfish translates it as "Firm roadway." I suspect something like "fixed roadbed" is more accurate. Slambo (Speak) 11:05, 21 April 2006 (UTC)
I believe what you mean is what we call Embedded Track here. Basically, it is rails mounted in some form of concrete panels, without ties. Skabat169 14:43, 30 July 2007 (UTC)

[edit] Maintenance question

 Please help improve this article or section by expanding it.
Further information might be found on the talk page or at requests for expansion. (January 2007)

How long do rails last? Are there pieces of steel laid down in the 1800s that are still carrying trains today, or must they be replaced on a more frequent basis? Does lack of use help or hurt longevity? -- Beland 15:42, 13 January 2007 (UTC)

Good Question. A typical rail on tangent track can last for approximately 600 million gross-tons. According to AAR the average Class 1 Freight Train last year was 3,163 tons, meaning the track will typically last for 189,693 trains. At 40 trains per day, this would be 4,472 days, or about 13 years. But all of this is dependent upon the size rail chosen (110 lb/yd vs. 136 lb/yd), quality of the ties and ballast, axle loading of the trains (100-ton and above cars punish the track), curves (rail on curves far faster), and other factors (metalurgical make-up of the rail and such). Also, once a rail has been used for mainline it is typically relaid somewhere less important, like a yard or industrial sidings. I doubt you could find any rail from the 1800s in part due to failure, and in part due to higher axle loadings today. I have seen some rail around from as early as the 1940s, but always in low axle loading situations. Here is a shot on Railpictures of some 1960s rail still serving on the NEC. Hope this helps. Skabat169 14:43, 30 July 2007 (UTC)

[edit] How does a rail work?

 It is requested that a diagram or diagrams be included in this article to improve its quality.
For more information, refer to discussion on this page and/or the listing at Wikipedia:Requested images.

In discussions of rail technology, I often see mention of "flanges" being either on the wheel or on the rail. This article could use a quick basic discussion and probably a diagram of one or more configurations of wheel and rail, showing how the train is kept from falling off the track. It might also be worth discussing why flanges are apparently so small - forces involved, etc. This article mentions 75-degree flanges and 1:20 tapers, and it would be helpful to explain such terms. -- Beland 17:11, 13 January 2007 (UTC)

This ties in with wheel profile, studied at BR Research Division in the sixties, along with suspension design and the prevention of hunting. Also from the Railchat forum: The rails in all track apart from 113A vertical S&C, are set so that the rails lean in towards the 4' at an angle of 1 in 20, this is referred to as being inclined. The reason this is done is so that in conjunction with a similar angle on the treads of the wheels a self centering action is set up. So that the wheel sets tend naturally to run down the middle of the track rather than rubbing against one of the rails.

It also acts as a differential on curves in that by moving outwards so the outside wheel is running on the part of the tread near the flange that has the largest radius, while the inner wheel is running on the smaller radius near the outer rim. A balance is thus achived in that the outer wheel which has to roll further than the inner wheel, while fixed by the axle into making the same number of turns. By virtue of running on the large radius does indeed travel further. 81.152.64.151 (talk) 19:01, 26 January 2008 (UTC)

[edit] Formula

V_{max}=\sqrt{\frac{E_a + 3}{0.0007d}}

looks better than the picture used in the article, i think:

[edit] Prevalence of Bullhead rail in the UK?

The article suggests that Bullhead rail has not been installed in the UK since the 1950s, whereas the prevalence of Bullhead rail in the UK today (from my observations) seems to suggest otherwise.

I can't quite figure out what the situation is. Is Bullhead still used to replace existing track, or is there actually track in use on the mainline today that is more than 50 years old? 217.155.20.163 23:05, 20 April 2007 (UTC)

Probably both. If there was large scale renewal rather than repair of as short length, then CWR would be used 81.152.64.151 (talk) 19:01, 26 January 2008 (UTC)

[edit] Pictures of US Fishplates?

It looks like most of the fishplates in the pictures are not from the U.S. Where I live, the fishplates do not look like that. They are just a plate with 4 holes in them for spikes. I can get a picture of them, but I don't have one of my own pictures right now. Tyb525 16:44, 5 June 2007 (UTC)

I'll see what I can dig up this week. I should be able to get a decent photo of one sometime. Slambo (Speak) 17:30, 5 June 2007 (UTC)

== Track dimensions ==
What are the dimensions of the rails used on the UK high speed lines & what is the interval between sleepers
[ i'm wanting to work out the deflection of the rail when a 10 tonne axle is in the middle of the gap}
anyone know please?
--83.105.33.91 12:02, 30 July 2007 (UTC)

Probably depends on spec of rail 81.152.64.151 (talk) 19:01, 26 January 2008 (UTC)

[edit] Oval Bolt Holes

It is mentioned that the bolt holes in fish (angle) plates are oval to allow for expansion. I believe that this is incorrect. The portion of the bolt shank nearest the head has an oval shape, which engages the oval in the plate. This prevents the bolt from rotating, so that only one wrench is required when tightening a bolt. LorenzoB 01:32, 16 October 2007 (UTC)

[edit] Concrete vs Steel sleepers

From Rail Chat: How does track using steel sleepers which are pretty well on the surface of the ballast react to changes in temperature?


Steel sleepers have their ends turned down into large spades that dig into the ballast to prevent movement, so no real problem. The first design of steel sleepers known as crimp ended did not have this feature, and are much less stable. They are for this reason treated differently for stressing and critical rail temperature calculations. (If you have ever seen the little blue book on heat precautions, the photo on the front of that is of crimp ended sleepers.) Being less than an outstanding success crimp ended sleepers were not used much and are I believe now quite rare. 81.152.64.151 (talk) 19:01, 26 January 2008 (UTC)

[edit] Formula Questions

The text mentions unbalanced superelevation of 4 with a waiver; when that happens, do you change the 3 in the formula to 4? Is there any maximum for E sub a?

When rail is being upgraded for higher speeds in the US, it frequently is not convenient to move it to an alternate right of way, so whatever curvature exists can limit the speeds. It would be nice if the article would more clearly explain in clear terms, if one sees a 90 degree turn in Google Maps that appears to have, say, a half mile radius, what the maximum speed that is achievable on that right of way would be. JNW2 (talk) 02:34, 10 April 2008 (UTC)

[edit] Continuous welded rail

FYI - I have created Continuous welded rail as a redirect, so you no longer need to use an anchored link to this article when referring to CWR. EdJogg (talk) 12:31, 14 April 2008 (UTC)

[edit] FRA track classes

Added an FRA source for the US track classes. There are some suspect comments in that list, though, that need fixing. Seems to me that mentioning the need for improved grade crossing warning is beyond the scope of the FRA track classes which address, strangely, track (and not signalling, etc). --plaws (talk) 16:41, 21 April 2008 (UTC)

From the article:

The class a track is placed in determines speed limits and the ability to run passenger trains.

I don't believe this is entirely true. I have no citeable source, but I believe things like crossing warnings and signaling are entirely separate from track class and that those affect speed limits more than anything. I.e., you could have Class 9 track, but without signals, you're not going to go over 49 mph. Anyone help a feller out here with a citation? --plaws (talk) 21:35, 22 April 2008 (UTC)