IMPROVEMENTS IN THE MANUFACTURE OF RAILWAY AND OTHER WHEELS
Year: 1845

page_text: LETTERS PATENT to Robert Hadfield, of Drummond Street, London,
for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF RAILWAY
AND OTHER WHEELS."
Sealed the 22nd June 1875, and dated the 4th March 1875.
PROVISIONAL SPECIFICATION left by the said Robert Hadfield at the
Office of the Commissioners of Patents, with his Petition, on the
4th March 1875.
I, ROBERT HADFIELD, of Drummond Street, London, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE MANU-
PACTURE OF RAILWAY AND OTHER WHEELS," to be as follows:-.
Hitherto it has been a general practice to use both for railway and
tramway wheels steel and wrought-iron tyres which have been forged.
and rolled in preference to wheels which have been simply cast and
are neither forged nor rolled, such practice originating in the idea that
wrought tyres from the rolling and compression received combine greater

page_text: or webbed form, so as to permit both of the expansion and contraction
of the metal, and which form imparts greater elasticity thereto at the
same time that it considerably reduces the strain on the tyre. I then
pour or otherwise introduce molten, crucible, or other steel or metal into
the casting box, the interior of which is so constructed as to form a
hollow die or cavity, space, or matrix, into which the molten metal runs
and assumes the required disc form. The exterior of this wrought tyre
I keep cold by suitable appliances, and it thus remains fibrous and is
stronger than the previously melted steel or metal, which cooling
quickly within the mould shrinks and contracts within the said tyre
inwardly on and in the direction of the wheel boss centre. Now it is a
well-known fact that steel whilst in the act of cooling is very weak and
rotten, but when cold, its fibre returning, the steel disc regains its
strength. Of this temporary weakness I take advantage, and conse-
quently the tyre becomes capable of resisting all pressure coming from
within and extending outward, and as the contraction occurs inwardly
all strain is removed off such tyre, which accordingly shrinks on and
adapts itself to the said disc in such a way as to become inseparable
therefrom. I afterwards remove such tyre with the disc and boss, which
in the interval will be found to have become so firmly united to each other
as to form one solid inseparable steel (or steel and metal) wheel. But in
order further to prevent any possibility of the tyre leaving such disc I
have a groove rolled inside such tyre when manufactured, somewhat like
a gutter or channel, and the square corners afterwards turned out in a
lathe, so that when the molten metal is run therein it cools and sets
within such groove, and thereby the tyre becomes securely keyed to the
disc and all danger of the disc getting loose or detached therefrom is
entirely prevented. Such groove may be applied to any existing tyre by
simply turning such groove therein in an ordinary wheel lathe. I after-
wards place such wheel in an annealing furnace, taking great care to
gradually heat and cool the same, which takes away all strain or undue
expansion off such wheel and tyre, as well as greatly toughening and
improving the same, and rendering it almost indestructible.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Hadfield in the Great Seal Patent Office on
tho 4th September 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
HADFIELD, of Drummond Street, London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourth day of March, in the year of
our Lord One thousand cight hundred and seventy-five, in the thirty-
cighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Robert Hadfield, Her special license
that I, the said Robert Hadfield, my executors, administrators, and
assigns, or such others as I, the said Robert Hadfield, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
THE MANUFACTURE OF RAILWAY AND OTHER WHEELS," upon the condition
(amongst others) that I, the said Robert Hadfield, my executors or
administrators, by an instrument in writing under my, or their, or one
of their hands and seals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be
performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said Robert Hadfield, do hereby declare
the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
Hitherto it has been a general practice to use both for railway and
tramway wheels steel and wrought-iron tyres which have been forged
and rolled in preference to wheels which have been simply cast and
are neither forged nor rolled, such practice originating in the idea that

page_text: Wrought tyres from the rolling and compression received combine greater
strength and durability than if simply cast without such compression.
Such wrought tyres are attached to tramway and railway wheel centres
by various methods. One method of attaching such wheels was Patented
in 1815 by and is known as Mansell's wheel, and many tramway wheels
are fastened by this process to wrought tyres. Among the objections
however urged against Mansell's wheels are the complicated fastenings,
the failure of the axle boss when break power is applied thereto, also
the liability of the wooden centres to rot in wet and shrink in dry
climates, and the unsuitability, of Mansell's fastenings to iron wheels,
arising from the fact that should the tyre break there is a complete
collapse, there being nothing beyond rings or bolts to secure it, and
these naturally giving away on losing their supports.
Now I have found that to render a railway or tramway wheel perfectly
safe it should be formed in a solid disc, and manufactured preferably of
the best steel, such solid disc having thereon an ordinary rolled steel or
wrought-iron tyre, so firmly constructed and connected thereto as prac-
tically to form one solid weldless or welded wheel without any fastenings
whatever; such wheel also requires to combine a sufficient degree of
clasticity to allow for the contraction of the metal by frost and cold, as
also to provide for the expansion thereof by heat. It must also combine
simplicity of construction with economy of manufacture, and it must
be so combined and constructed that if the tyre fail or splinter in
numerous fragments none of such fragments can escapo from the grip of
such disc and tyre.
Now in order to manufacture a wheel possessing these various requi-
sites, and thereby prevent the recurrence of accidents arising from tho
breaking of the tyres or other parts of railway or tramway wheels, I
have invented the following method of manufacturing such wheels, in
which I entirely dispense with all tyre fastenings, so that there are
neither bolts or fastenings to break or get loose:-I take a steel, wrought-
iron, or other mould, and place a steel or wrought-iron tyre therein,
which may be either heated or cold, and form and mould the same with
a boss or nave having an axle hole therein, thus forming a wheel centre,
hereafter called the disc, such disc being about one inch in thickness,
but I do not confine myself to this exact form or configuration, which

page_text: may be varied to suit special requirements. I prefer to make the disc of.
a corrugated or webbed form, so as to permit both of the expansion and
.contraction of the metal, as such webbed form not only imparts greater
.clasticity thereto,, but at the same time considerably reduces the strain
on the tyre. I then pour or otherwise introduce molten, crucible, ord
other steel or metal into the casting box, the interior of which is so con-
structed as to form a hollow die or cavity, space, or matrix, into which
the molten metal runs and assumes the required disc form. The exterior
of this wrought tyre I keep cold by suitable and well-known appliances,
and it thus remains fibrous and becomes stronger than the previously
melted steel or metal, which cooling quickly within the mould shrinks
and contracts within the said tyre inwardly upon and in the direction of
the wheel boss centre. Now it is a well-known fact that steel whilst in
the act of cooling is very weak and rotten, but when cold its fibre
returning the steel again regains its strength. Of this temporary weak-
ness I take advantage, and consequently the tyre becomes capable of
resisting all pressure coming from within and extending outward, and as
the contraction occurs inwardly all strain is removed off such tyre, which
accordingly shrinks on and adapts itself to tho said disc in such a way
as to become inseparable therefrom. I afterwards remove such tyre
with the disc and boss, which in the interval will be found to have.
become so firmly united to each other as to form one solid inseparable
steel (or steel and metal) wheel. But in order further to prevent any.
possibility of the tyre leaving such disc I have a groove rolled inside
such tyre when manufactured, somewhat like a gutter or channel, and
the square corners afterwards turned out in a lathe, so that when the
molten metal is run therein it cools and sets within such groove, and
thereby the tyre becomes securely keyed to the disc, and all danger of
the disc getting loose or detached therefrom is thus entirely prevented.
Such groove may also be applied to any existing tyre by simply turning
such groove therein in an ordinary wheel lathe. I afterwards place such
wheel in an annealing furnace, taking great care to gradually heat and
cool the same, which takes away all strain or undue expansion off such
wheel and tyre, as well as greatly toughening and improving the same,
and rendering it almost indestructible.
Having
"

page_text: have it understood that I claim, improvements in the manufacture
of railway and other wheels, substantially in the manner and for the
purposes herein-before set forth and described.
In witness whereof, I, the said Robert Hadfield, have hereunto set
my hand and seal, this Third day of September, in the year of
our Lord One thousand eight hundred and seventy-five.