Improvements in Railway Tracks.
Year: 1890

page_text: Date of Application, 15th July, 1890-Accepted, 30th Aug., 1890
Improvements in Railway Tracks.
I, PLIMMON HENRY DUDLEY of No. 54 Pine Street, in the City of New York,
in the State of New York, United States of America, Civil Engineer, do hereby
declare the nature of this invention and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement:-
-
A careful and correct inspection of railway tracks which have been in use for some
time, discloses the following state of facts:
The least wear of rails is on the level tangents; on the gradient tangents it is from
two to three times as great as on the level, for the same tonnage, while along the
curves it is still greater, especially where the curves are on gradients.
In the latter case, very severe cutting of the inside head of the outer rail takes
place in addition to the increased surface wear of the rails due to the slipping which
takes place on all curves.
Where tracks are laid with a uniform section of rail, this unequal wear requires
the renewal of such rails as are the most worn, and when these are replaced by new
rails, the portion of the track not new seems to ride very poorly as compared with the
part renewed. This result has induced most of the roads to renew their rails in long
stretches, removing not only those rails which are most worn, but, together with
them, those which are only partially worn, thereby losing the benefit of the use of
the partially worn rails for the remainder of their natural life.
The object of my invention is to provide a track in which the life of the rails shall
be substantially uniform throughout the level, gradient, and curved portions; and
to this end I provide a rail of sufficient stiffness, width, and depth of head, to carry
the traffic on the level tangents for a number of years with a certain amount of
wear, and this, for convenience, I term the light section of a series. For the gradient
tangents, I provide a rail of greater wearing capacity, either by increasing the depth
of the head or the width of the head, or both, and at the same time increasing the
dimensions of the web and base, if necessary, in order to maintain the same
proportionate stiffness of the section. This rail, I prefer to term the medium section
of the series. For the curves, where the wear is still greater, I provide a rail of
greater wearing capacity, by still further increasing the depth or width of the head,.
or both, and, as before, in order to maintain a proportionate stiffness, I prefer. to
increase the dimensions of the web and base. This latter provision is also of
importance in order to equalize the cooling strains in the manufacture of the series.
In the accompanying drawings:
Fig. 1 represents a portion of track comprising a level, gradient, and curved
section, with the respective rails in position thereon, as in practical use.
Figs. 2, 3, and 4 represent, in end elevation, different rails of the series.
Fig. 5 represents the cross section of track of a level track section; and
Fig. 6 represents a cross section of track of a curved section.
In laying the track, I preserve the same inside gauge throughout all sections of
the series, but because of the increase in the width of the heads of the rails, the
actual extent of contact of the tread of the wheel with the rail will be increased for
the medium section, and still further increased for the heavy section. This will
clearly appear by reference to Fig. 1 of the drawings, in which the level section of
track is denoted by A, the gradient section by B, and the curved section by C, the
rails of the level section, or the light rail section, being represented by a, the medium
by b, and the heavy rail section by c. The narrow head of the level section is denoted
by at, the wider head of the gradient section is denoted by b¹, and the still wider
head of the curved section is denoted by c'.

page_text: Because of the fact that the percentage of tangent sections is in excess of the
percentage of curved sections on a line of road, it follows that the treads of the
wheels are worn to a narrower bearing (see, for example, D, Fig. 5) than the bearing
would be on a curve laid with rails having the wider heads c¹. In passing along
curves, the axles of the wheels do not stand parallel with the radii of the curve, but
if, in any position, the line of the axle were prolonged, it would extend in advance
of the centre of the curve, and this position would throw the flange of the outer
wheel into such a position relative to the rail, that it would tend to contact with the
inner edge of the head of the outer rail in front of the line drawn through the
centre of the wheel perpendicular to the head of the rail.
When, however, the head of the rail is widened, as at c', the outside edge d of
the worn tread of the wheel on the inside of the curve, will contact with the outer
edge e of the head of the rail on the inside of the curve, and will tend to hold the
flange F of the wheel on the outside of the curve away from the inner edge of
the head of the rail on the outside of the curve, and thereby prevent the serious
cutting away of said rail.
This holding of the flange of the outer wheel away from contact with the rail, is
a great advantage not only in preventing abrasion of the rail, but also in reducing
the retarding friction.
Such widening of the head on the curves, therefore, renders it feasible to reduce
the width of the head of the outer rail as compared with the width of the head of
the inner rail (see, for example, dotted lines Fig. 6), and still secure substantial
uniformity of the lives of the rails.
While I prefer to utilize the special advantage due to a widening of the head of
the rail in connection with a deepening of the same, as herinabove set forth, the
increase in the depths of the head might alone be inade sufficient to render the lives
of the different sections substantially uniform, or the widening alone might be
employed.
I also find it advisable, in general, to increase the dimensions of the web and base
of the rail, their thickness and height, to keep up the most approved proportions of
the same, to the increased dimensions of the head."
The meeting ends of the rails of varying heights and thicknesses, may be
connected by fish plates of any well known and approved form, adapted for the
purpose.
Having determined the increase of wear of a uniform rail section along its gradient
tangents, over that along its level tangents, and the increase of wear along its curves
and gradient curves over that along its level tangents or gradient tangents, the
particular amount of increase in the depth or width, or both, of the head of the rail,
to withstand the increased wear, may be satisfactorily determined, and the light,
medium, and heavy rail sections disposed in such order as to render the lives of the
rails substantially uniform throughout the line of road.
At prominent stations, yards, intersecting points, and terminals, where many
trains are stopped and started, increasing the wear on the rails, I also employ the
medium or heavy section, to provide for the increased wear, as the case might
require.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is :-
:-
1. In a railway track, a series of rail sections having heads of different dimensions
in cross section, and arranged with relation to the level, gradient, and curved
sections of the road, substantially as set forth.
2. A railway track in which the rails constituting curved portions of the track,
have the bearing faces of their heads wider than the bearing faces of the heads
of those rails which constitute the tangent portions of the track, substantially as
set forth.

page_text: 3. A railway track in which the rails constituting the curved portions of the
track, have their heads deeper than the heads of those rails which constitute the
tangent portions of the track, substantially as set forth.
4. A railway track in which the rails constituting the curved portions of the track,
have their heads both wider and deeper than the heads of those rails which constitute
the tangent portions of the track, substantially as set forth.
5. A railway track in which the rails constituting the gradients have their heads
wider than the heads of those rails which constitute the level portions of the track,
substantially as set forth.
6. A railway track in which the rails constituting the gradients have their heads
deeper than the heads of those rails which constitute the level portions of the track,
substantially as set forth.
7. A railway track in which the rails constituting the gradients have their heads
wider and deeper than the heads of those rails which constitute the level portions
of the track, substantially as set forth.
8. A railway track in which the rails constituting the curved portions are deeper
than those rails which constitute the tangent portions of the track, substantially as
set forth.
9. A railway track in which the rails constituting the gradients are deeper than
the rails which constitute the level portions of the track, substantially as set forth.
Dated thin 15th day of July 1800
NEWTON & SON,
Agents for the Applicant.