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Why all the different rail weights/profiles

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  • Member since
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  • From: Mesa, AZ
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Posted by silicon212 on Wednesday, May 27, 2009 10:33 PM

OK, I am going to throw a curve ball into this thread.  What's the deal with so-called head-free rail?  I am aware that SP used it extensively, and it's the rail that's used on 99% of the Phoenix line, but why that and what are the pros and cons to using it?

 For others, head-free rail has a head profile that's different than standard rail - it tapers inward toward the web from about 1" below the wheel surface vs. the conventional design which most people are familiar with.

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Posted by Texas Zepher on Wednesday, May 27, 2009 10:27 PM

Murphy Siding
How did the rail business evolve, that there were/are so many differing weights and profiles of rail used out there?

Simple economy and open market place.  Why use heavy rail on an industry track that gets a couple of cars a week?  Likewise one can't use light rail on a high speed, high volume mainline.  Through time as railcars weighed more the rail had to get heavier to handle them.   Same thing for the profiles.  Companies (rail vendors) trying to get the most strength in a rail (marketing) using the least amount of material (aka least cost - greater profit).  Then as materials improved, the profiles could change to take advantage of it.

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Posted by TomDiehl on Wednesday, May 27, 2009 10:25 PM

Murphy Siding

     How did the rail business evolve, that there were/are so many differing weights and profiles of rail used out there?

As best I can understand your question:

In the early days, once they moved away from strap rail, the rail profiles were a function of the rolling process available at the time. As the rolling techniques improved, the common profile, used even today, is the T-rail, which gives the best strength and workable profile with economy of the material. The different sizes, usually referd to as the rail weight, started with the smaller rails and got larger to handle heavier cars and locomotives as the rolling stock technology allowed for larger and heavier loads. Today, traffic levels also determine the weight of rail used, lighter traffic areas will receive lighter rail because it's cheaper. High traffic areas will get the heavier rail because the cost of replacing the rail more often (both money and loss of track use costs) exceeds the cost difference of the lighter compared to heavier rail.

Smile, it makes people wonder what you're up to. Chief of Sanitation; Clowntown
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Why all the different rail weights/profiles
Posted by Murphy Siding on Wednesday, May 27, 2009 10:02 PM

     How did the rail business evolve, that there were/are so many differing weights and profiles of rail used out there?

Thanks to Chris / CopCarSS for my avatar.

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