IMPROVEMENTS IN MOULDS OR APPARATUS TO BE USED IN CASTING STEEL."
Year: 1867

page_text: LETTERS PATENT to John Martin Rowan, of Glasgow, in the County of
Lanark, North Britain, Engineer, for the Invention of "IMPROVEMENTS
IN MOULDS OR APPARATUS TO BE USED IN CASTING STEEL."
PROVISIONAL SPECIFICATION left by the said John Martin Rowan
at the Office of the Commissioners of Patents, with his Petition, on the
27th December 1867.
I, JOHN MARTIN ROWAN, of Glasgow, in the County of Lanark, North
Britain, Engineer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN MOULDS OR APPARATUS TO BE USED IN CASTING STEEL," to be
as follows, that is to say:-
This Invention relates to improvements whereby steel may be cast more
satisfactorily than heretofore, and so as to be free from the small holes or
"honeycomb " texture ordinarily met with when it is cast in cast iron, dry
sand, or composition moulds, and the Invention consists,
Firstly. In making the moulds and cores of malleable or wrought iron or
of steel.
Secondly. In making the tops and bottoms of the moulds also of malleable
iron or steel.

page_text: Thirdly. In adapting to the moulds collapsing cores consisting of segments
of malleable iron or steel, with or without a backing of sand and central
collapsing sheet iron cylinder.
And, fourthly. In making the mould or core surfaces of greensand in
order to the more rapid reduction of the temperature of the cast steel, instead
of making them of dry sand or dry composition as heretofore.
When the mould or core surfaces are formed of wrought iron or steel the
metal of the steel casting adjacent to them does not turn out porous as in the
moulds ordinarily employed, but is close and compact; and the improvement
obtained by these means is of very great importance when the steel is cast in
the form of thick hoops for the manufacture of railway tires. Various forms
of collapsing cores with wrought iron or steel segments may be used. In
one modification there are four external segments which when in position
enclose a square; filling up pieces are applied at the angles of this square,
and sand is packed in between these parts, and a central cylinder of thin
sheet metal arranged so that it can be easily contracted like a coiled spring.
As soon as the steel newly cast into the mould begins to solidify the central
cylinder is contracted and withdrawn, whereupon the sand can be easily
broken down and the segments be collapsed. The use of green sand for the
mould surfaces or for parts thereof has also a better action on the molten
steel coming in contact with it than the dry sand or dry composition heretofore
considered essential to such moulds. The mould bottoms made of malleable
iron or steel may be constructed with passages or cavities for water or air to
cool them if found desirable.
The present improvements are of great advantage when applied to steel
made by the Bessemer process.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Martin Rowan in the Great Seal Patent Office on the
26th June 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
MARTIN ROWAN, of Glasgow, in the County of Lanark, North Britain,
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of December, in the year of our
Lord One thousand eight hundred and sixty-seven, in the thirty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,

page_text: the said John Martin Rowan, Her special licence that I, the said John
Martin Rowan, my executors, administrators, and assigns, or such others as
I, the said John Martin Rowan, 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 "IM-
PROVEMENTS IN MOULDS OR APPARATUS TO BE USED FOR CASTING. STEEL," upon the
condition (amongst others) that I, the said John Martin Rowan, 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 John Martin Rowan, do hereby:
declare the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement in writing, reference being had to the accompanying
Drawings, that is to say:-
My said Invention relates to improvements whereby steel may be cast
more satisfactorily than heretofore, and so as to be free from the small holes
or "honeycomb " texture ordinarily met with when it is cast in cast iron,
dry sand, or composition moulds, and my Invention consists in making the
moulds and cores of malleable or wrought iron or of steel.
.
Secondly. In making the tops and bottoms of the moulds also of malleable
or wrought iron or of steel.
Thirdly. In adapting to the moulds collapsing cores consisting of segments
of malleable or wrought iron or of steel, with or without a backing of sand
and central collapsing sheet iron cylinder.
:
:
And, fourthly. In making the mould or core surfaces of greensand in-
order to the more rapid reduction of the temperature of the cast steel, instead
of making them of dry sand or dry composition as heretofore.
When the mould or core surfaces are formed of wrought iron or steel
the metal of the steel casting adjacent to them does not turn out-porous:
as in the moulds ordinarily employed, but is close and compact; and the
improvement obtained by these means is of very great importance-when-
the steel is cast in the form of thick hoops for the manufacture of -railway
tires.

page_text: And in order that my said Invention and the manner of performing the
same may be properly understood, I have, hereunto appended a Sheet of
explanatory Drawings to be herein-after referred to, and representing by way
of example various modifications of my improved arrangements. The same or
like parts are distinguished by the same reference numerals in all the Figures
in which they occur.
Figure 1 is a vertical section of a mould for casting a steel hoop or ring
for being manufactured into a railway tire, and Figure 2 is a corresponding
plan.
In this example the body or circumferential part 1 of the mould is of
malleable or wrought iron, whilst the top 2 and bottom 3 are of cast iron; as
in ordinary cases. The mould is represented as placed on a standing plate 4
constructed for free access of air at the sides and below, and which receives a
series of moulds in succession and facilitates their being placed accurately in
position. The standing plate 4 is itself fixed on a stool or other support
arranged to allow access of air beneath it. Various forms of collapsing cores
with wrought iron or steel segments, may be used.
In the modification shown in Figures 1 and 2, and of which parts are
shown full size in Figure 3, there are four external segments 5, the adjacent
edges of which are shaped to fit upon the corners of a square; filling-up
pieces 6 are applied at the angles of the square, and sand 7 is packed. in
between these parts, and a central cylinder 8 of thin sheet metal arranged so
that it can be easily contracted like a coiled spring.
In Figures 1 and 2 the mould is represented as ready for receiving a cast
the core 5 being in position, and the parts of the mould being held together
by clamps 9, whilst the pouring gate 15 is placed in the aperture provided for
it in the cover. The internal surfaces with which the melted metal comes in
contact may either be left quite bare and clean, or they may be coated with a
very thin wash of fire-clay and water. As soon as the steel newly cast into.
the mould begins to solidify the central cylinder 8 is contracted by the
application of a pair of tongs to the internally projecting flanges 10,
whereupon the sand 7 can be easily broken down and the segments 5 be,
collapsed.
....
Figure 4 is a vertical section, and Figure 5 is a plan of a modification of
my improved mould, in which the top 12 and bottom, 13 are of malleable or
wrought iron, or of steel, as well as the sides 1. The bottom 13 rests on
radial ribs on a cast-iron bottom plate 14, the spaces between which ribs allow
free access of air to the outer surface of the bottom 13. The spaces between
the ribs may be arranged to receive water for cooling if found desirable. This

page_text: mould is represented as fitted with a collapsing core 5, parts of which are
shown full size in Figure 6. The segments 5 are slightly different in shape
from what is shown in Figures 2 and 3, whilst the backing of sand (7) is
dispensed with, and the segments are kept out by two spring bands 8.
Figure 7 is a vertical section of a form of my improved mould suitable for
casting steel ingots, and Figure 8 is a plan of the same as inverted. In this
modification the body 1 of the mould is made of malleable or wrought iron or
of steel, and in two halves which are held together by a series of cast-iron
rings 16. These rings are shaped, as best seen in Figure 8, with inwardly
projecting edges to reduce the contact surfaces as much as possible, and to
allow access to the air.
Figure 9 is a plan showing a different shape of ring 16 with reduced
contact surfaces; Figure 10 is a plan showing the mould I as formed in one
piece, instead of being in two halves. The mould may of course be adapted
to give various shapes to the ingots; thus in Figure 11 a mould is shown for
a four-sided ingot, and as composed of four segments 1.
Figure 12 shows a mode of fitting together segments for a four-sided
mould, and Figures 13, 14, and 15, show different modes of constructing the
corner parts of four-sided moulds, so as to avoid too acute an angle, it being
found that when a rounded shape is given to the corners either in ingot
moulds or hoop moulds the castings are sounder at those parts and exhibit
less tendency to crack.
In some cases greensand may be used for a part of the mould surface,
namely, for the core, such greensand being by preference applied upon a
collapsing sheet iron cylinder, and having a better action on the molten steel
coming in contact with it than the dry sand or dry composition heretofore
considered essential; I, however, prefer to use cores of wrought iron or steel
as herein-before described.
My present improvements are of great advantage when applied to steel
made by the Bessemer process.
Having thus particularly described my said Invention, and the manner in
which the same is to be performed, I have to state that I do not restrict
myself to the precise details herein described or delineated, but that what I
believe to be novel and original and claim as the Invention secured to me by
the herein-before in part recited Letters Patent is,―
The using of malleable or wrought iron or steel in making moulds for
casting steel, substantially in the manner and for the purposes herein-before
described.

page_text: And the constructing of collapsing-cores to be used in moulds for casting
steel hoops, substantially in the manner herein-before described.
In witness whereof, I; the said John Martin Rowan, have hereunto set
my hand and seal; this Twenty-fifth day of June, in the year of our
Lord One thousand eight hundred and sixty-eight.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
JNO. M. ROWAN. (L.8.)