Gauge tolerances

Discussion in 'FAQs' started by mhdishere, Jun 7, 2004.

  1. mhdishere

    mhdishere Member

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    While waiting for my 12-inch-to-the-foot commuter train this morning, someone I see there every morning was wondering how close the tolerances are on standard gauge track. I know the gauge is 4' 8 1/2", but how far off can they be and still be considered "in gauge"? Anybody know?
  2. cidchase

    cidchase Active Member

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    Hi mhd,

    From this accident report:
    http://ncsp.tamu.edu/reports/TSB/r95d0016.htm

    "Post-derailment track measurements immediately north of the area of track destruction revealed gauge to be 58-1/2 inches at one location, and 58 inches at several locations. Transport Canada's (TC) Track Safety Rules stipulate a maximum allowable gauge of 58-1/2 inches for this class of track. Standard gauge is 56-1/2 inches. "

    So, in this case, the max is 2" wide. I can hardly believe that all passenger
    routes have this much tolerance. It's a real good question!!!!!
  3. cidchase

    cidchase Active Member

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    From a 2000 reprt on CSX:
    http://www.utu.org/DEPTS/PR-DEPT/NEWS/ndigest/2000/March2m/ND3-31.HTM

    "The FRA noted that two of the three recent track-caused derailments were caused by wide gauge, including a minor derailment of Amtrak’s Chicago-Washington Capitol Limited at Connellsville, Pa., on Jan. 30. The width between rails is supposed to be 56 1/2 inches. The inspection found numerous spots around the CSX system where the gauge was spread one inch to 1 1/2 inches
    too wide.

    On another CSX route used by Amtrak’s Washington-Chicago Cardinal--the North Mountain subdivision from Charlottesville to Clifton Forge, Va.--the FRA equipment found 23 locations with a gauge of 57 3/4 inches or more, poor crosstie condition and many curves with insufficient spikes to hold the track in proper gauge. Informed of the conditions, a senior CSX official inspected the track and immediately reduced the passenger train speed limit from 60 mph to 40 mph.
    The FRA report recommended civil penalties for conditions found on that 97-mile subdivision.

    On a line in North Florida where Amtrak’s Orlando-Los Angeles Sunset Limited travels at up to 79 mph, the agency found 23 instances of wide gauge, including three greater than 58 inches. Civil penalties were also recommended for those defects."

    How safe are we?? :eek:
  4. Fred_M

    Fred_M Guest

    Yeah, it's a big problem if a loco drops down between the rails at speed. :( FRED
  5. cidchase

    cidchase Active Member

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    From a 2002 story on an Amtrak derailment (with fatalities):

    http://www.cbsnews.com/stories/2002/04/19/eveningnews/main506768.shtml

    "While Amtrak uses 22,000 miles of track across the country, it owns and maintains owns only about 700 miles of it, mostly along the crowded Washington New York Boston corridor. Elsewhere, freight railroads like CSX own and maintain the tracks, with no oversight from Amtrak. " :( :(
  6. cidchase

    cidchase Active Member

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    The Straight Skinny

    http://nyow.railfan.net/rrdata/49CFR213.html

    US CODE TITLE 49--TRANSPORTATION
    CHAPTER II--FEDERAL RAILROAD ADMINISTRATION,
    DEPARTMENT OF TRANSPORTATION
    PART 213--TRACK SAFETY STANDARDS

    Subpart A--General

    Sec. 213.9 Classes of track: operating speed limits. (a) Except as provided in paragraph (b) of this section and Secs. 213.57(b), 213.59(a), 213.113(a), and 213.137(b) and (c), the following maximum allowable operating speeds apply-- [In miles per hour]

    The maximum The maximum
    Over track that meets all of the allowable allowable
    requirements prescribed in this operating speed operating speed
    part for-- for freight for passenger
    trains is-- trains is—
    ------------------------------------------------------------------------
    Excepted track ........................... 10 ............... N/A
    Class 1 track ............................ 10 ............... 15
    Class 2 track ............................ 25 ............... 30
    Class 3 track ............................ 40 ............... 60
    Class 4 track ............................ 60 ............... 80
    Class 5 track ............................ 80 ............... 90
    ------------------------------------------------------------------------

    Sec. 213.53 Gage. (a) Gage is measured between the heads of the rails at right-angles to the rails in a plane five-eighths of an inch below the top of the rail head. (b) Gage shall be within the limits prescribed in the following table--
    ---------------------------------------------------------------------------------------------
    Class of track The gage must be at least-- But not more than—
    ---------------------------------------------------------------------------------------------
    Excepted track..........................N/A .......................... 4' 10 1/4"
    Class 1 track........................... 4' 8" .......................... 4' 10"
    Class 2 and 3 track..................4' 8" ......................... 4' 9 3/4"
    Class 4 and 5 track..................4' 8" .......................... 4' 9 1/2"
    ---------------------------------------------------------------------------------------------

    So there you have it!!!! :D :D :D :D :D :D
  7. RailRon

    RailRon Active Member

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    Yesterday night I saw a report on TV about our new Swiss high-speed line 'Railroad 2000' with passenger speeds up to 145 mph.

    Standard gauge (here of course we have metric measurement in millimeters) is 1435 mm wide.
    The tolerances for high-speed track are from minimum gauge -1 mm up to maximum +3 mm. High-precision track laying! :thumb:
    (On normal track it might be about 3 times as big, but still only up to + 10 mm).

    BTW at some point we have a turnout where a branch line is leading away from the main line. It is about 120 meters (360 ft) ft long and its points are moved and locked by no less than eight (!) motors. But then you can slam through the diverging track with 125 mph! (In H0 this turnout had a length of 1.3 meters (or 55")! :eek:

    Ron