IMPROVEMENTS IN THE MANUFACTURE OF RAILWAY WHEELS
Year: 1855

page_text: PROVISIONAL SPECIFICATION left by the said Henry Bessemer at the
Office of the Commissioners of Patents, with his Petition, on the
18th June 1855.
I, HENRY BESSEMER, of Queen Street Place, New Cannon Street, in the
City of London, Engineer, do hereby declare the nature of the Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF RAILWAY WHEELS" to be as
follows:-
These improvements are intended to lessen the weight and increase the
durability of wheels used to run on railways; for which purpose I prepare a
mould of the wheel in dry loam or sand, after the usual manner of preparing
moulds for founding in iron; into this mould I run or pour molten steel, and
thereby obtain a cast steel wheel complete in one piece, although any separate
portion of the wheel may be so formed. if desired. The great strength of this:
material as compared with iron will admit of a considerable reduction in the

page_text: weight of the wheel, while at the same time its superior hardness will render it
capable of withstanding the rolling action on the rails for a much longer period
of time than wheels made of wrought iron. After the wheel is cast, it should
be put into an annealing oven of any convenient form, and be there kept for
several hours at a red heat, in order to toughen the steel as much as possible.
When a great degree of hardness is desired on the external surface of the tyre,
that part of the wheel may be cast against an iron "chill," while the remaining
portions of the wheel are cast in sand, or other slow conductor of heat; or the
wheel after it has been turned and finished may have its tyre hardened by
quenching it in water or oil while in a heated state. In some cases I use a
mixture of steel and pig or refined iron for casting railway wheels, as it is less
expensive than steel alone. The proportion of iron used with the steel will vary
with the qualities desired in the wheel; I have found from one-third part to
two-third parts of iron give a good result, but the quantity may be greatly
varied. The same mode of casting, annealing, chilling, or hardening may be
followed with the wheel when formed of a mixture of iron or steel, as herein-
before stated in reference to the use of steel alone. The steel or mixture
of steel and iron may be melted in crucibles, as at present practised in the
melting of cast steel, the contents of several crucibles being poured' simul-
taneously into the mould; but I prefer that the process of melting steel or
steel and iron mixed should be used for the purposes of this Invention, as
set forth in the Provisional Specification of a Patent for "Improvements
in the Manufacture of Cast Steel & Mixtures of Steel and Cast Iron,"
bearing even date herewith.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Bessemer in the Great Seal Patent Office on the
18th December 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
BESSEMER, of Queen Street Place, New Cannon Street, in the City of London,
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighteenth day of June, in the year of our Lord
One thousand eight hundred and fifty-five, in the eighteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the

page_text: said Henry Bessemer, Her special licence that I, the said Henry Bessemer,
my executors, administrators, and assigns, or such others as I, the said Henry
Bessemer, 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 MANUFAC-
TURE OF RAILWAY WHEELS," upon the condition (amongst others) that I, the
said Henry Bessemer, by an instrument in writing under my hand and seal,
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 Henry Bessemer, do hereby declare the
nature. of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof (that is to say) :-
These improvements are intended to lessen the. weight and increase the
durability of wheels used to run on railways; for which purpose I prepare a
mould of the wheel in dry loam or sand, after the usual manner of preparing
moulds for founding in iron; into this mould I run or pour molten steel, and
thereby obtain a cast steel wheel complete in one piece, although any separate
portion of the wheel may be so formed if desired. The great strength of this
material as compared with iron will admit of a considerable reduction in the
weight of the wheel, while at the same time its superior hardness will render
it.capable of withstanding the rolling action on the rails for a much longer
period of time than wheels made of wrought iron.
In the preparation of the mould, care must be taken that no extraneous
matters capable of forming gas enter accidentally into the materials of which
the mould is composed, otherwise the extreme heat of the metal will produce
so much gaseous matter as to blow or spoil the casting. I therefore recom-
mend that the loam or sand mould be brought to a low red heat previous to.
the pouring in of the melted steel; the sand or loam should also be left-so
porous as to admit the expanded air to pass freely through it and at all
parts where any air could possibly be locked in, small holes must be made for
its escape. After the wheel is cast, it should be put into an annealing oven
of any convenient form, and be there kept for several hours-at-a red heat,
in order to toughen the steel as much as possible.

page_text: A full red heat should be maintained for about twelve hours, after which the
temperature of the oven may be allowed gradually to diminish, until the wheel
is sufficiently cool to be removed from the oven by hand: The most convenient
way to reduce the temperature is to stop with clay all access to and egress
from the oven during the cooling process.
When a great degree of hardness is desired on the external surface of the
tyre, that part of the wheel may be cast against an iron "chill," while the
remaining portions of the wheel are cast in sand, or other slow conductors of
heat; or the wheel after it has been turned and finished may have its tyre
hardened by quenching it in water or oil while in a heated state. In some
cases I use a mixture of steel and pig or refined iron for casting railway
wheels, as it is less expensive than the steel alone. The proportion of iron used
with the steel will vary with the qualities desired in the wheel; I have found
from one-third part to two-third parts of iron give a good result, but the
quantity may be greatly varied. The same mode of casting, annealing, chilling,
or hardening may be followed with the wheel when formed of a mixture of
iron and steel, as herein-before stated in reference to the use of steel alone,
more especially with regard to the drying and heating, of the mould previous
to the pouring in of the fluid metal. I would also observe that a large runner
head of metal should be employed in founding in steel or mixtures of steel
and iron. It will be found preferable to cast the nave of the wheel solid
and to form the runner above it, and to make several openings for the
escape of air from the mould at the tyre part of the wheel, the boss or nave
of which may be bored out, and the tyre finished by turning in a lathe in the
usual way.
:
The steel or mixture of steel and iron may be melted in crucibles as at
present practised in the melting of cast steel, the contents of several crucibles
being poured simultaneously into the mould; but I prefer that the process of
melting steel or steel and iron mixed should be used for the purposes of this
Invention, as set forth in the Provisional Specification of a Patent for "Im-
provements in the Manufacture of Cast Steel and Mixtures of Steel and Cast
Iron," bearing even date herewith, and whereby the steel or mixture of steel
and iron may be melted in crucibles of larger capacity than those now in
general use for melting steel, and by which means also the fluid metal may be
run into the mould without removing the said crucibles from the fire, as set
forth in the Specification of a Patent granted to me, and filed simultaneously
with this present Specification, and entitled "Improvements in the Manufacture
of Cast Steel and Mixtures of Steel and Cast Iron."

page_text: Having thus described the nature of my Invention, and in what manner the
same is to be carried into effect, I claim,―
Firstly, the casting or founding of railway wheels in molten steel.
Secondly, I claim the founding or casting of railway wheels in a mixture of
steel and pig or refined iron.
In witness whereof,-I, the said Henry Bessemer, have hereunto set my
hand and seal, this Fifteenth day of December, in the year of our Lord
One thousand eight hundred and fifty-five.
Witness,
JNO. ALCOCK.
HENRY BESSEMER. (L.s.)