Improvements in Casting Apparatus.
Year: 1897

page_text: Date of Application, 30th Nov., 1897-Accepted, 15th Jan., 1898
Improvements in Casting Apparatus.
I, FREDERICK WILLIAM WOOD, of Baltimore in the State of Maryland, United
States of America, President of the Maryland Steel Co., 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:-
This invention has reference to the casting of metals and relates more particularly
to an apparatus for casting ingots in a continuous length or bar, the object being
to avoid the imperfect casting usually produced in stationary molds wherein the
shrinkage and sinking of the metal on cooling produces hollows and other defects
in the iugot.
With this end in view, my invention consists in combining with a stationary
mold containing an opening therethrough from end to end, a movable lining to
receive the molton metal and means for controlling the movement of said lining
to discharge the casting from one end of the mold as the molten metal is con-
tinuously introduced into its other end.
The invention also consists in the details of construction and combination of parts
hereinafter described and claimed.
In the accompanying drawings,
Figure 1 is a vertical sectional elevation through my improved apparatus on
the line aa of Figure 2;
Figure 2 is a top plan view of the same;
Figure 3 is a horizontal section on an enlarged scale through the mold and its
lining on the line bb of Figure 1;
Figure 4 is a similar view with the parts in slightly modified form.
Figure 5 is a sectional elevation of still another modification.
Referring to the drawings,
My improved apparatus comprehends mainly a stationary mold having an
opening therethrough from end to end and a movable lining in the form of thin
steel polished bauds B B B and B extending through the opening in the mold
and jointly covering its interior surface. The mold is in the present instance
formed with an opening square in cross section and is provided with chambers 2
for the circulation of a cooling medium, such as water, cold air, etcetera. It is in
two sections, as shown in Figure 3, to permit of the removal of the bands when
necessary, and these sections are connected together firmly by bolts 3, as plainly
shown in Figure 2. The mold is sustained in a fixed vertical position by means
of lugs on its opposite sides adapted to be seated on lugs 5 projecting inwardly
from two standards 6 constituting a frame which gives support also to the operative
parts of the apparatus hereinafter described. These two standards are of right-
angular form in cross-section and are sustained on a bed plate 7 with the apexes
of the angles facing each other, the bed plate being supported in turn by columns 8.
The four bands before alluded to constituting the lining of the mold enter the
top of the mold, at which point the interior faces of the mold are rounded or

page_text: curved outward to facilitate the introduction of the molten metal between the bands
and the latter extend flatly over these rounded portions of the mold downward
through the mold and outward at its lower end. The band B' passes over an upper
guide wheel 9 mounted in a bearing block 10 which is in turn mounted to move
to a limited extent vertically in guides 11 formed in the upper end of the standard 6
at one side. It also passes over a lower drive wheel 12 fixed to a shaft 13 mounted
in a hanger 13 and a bearing sustained by the standard below the guide wheel.
The other bands B B and B are similarly guided and driven by guide wheels 14,
14" and 14 and lower drive wheels 15, 10 and 15, which wheels are mounted in
bearings similar in form and arrangement to those just described. From the fore-
going description it will be seen that the four bands are arranged opposite each
other in pairs and completely cover the four interior faces of the mold, passing into
the upper end of the mold from the four guide wheels vertically downward through
the same and from its lower end over the drive wheels. Motion is imparted to the
drive wheel 12 from any suitable source through its shaft 13, which is extended
at one side as shown in Figure 2 to receive the power. From this shaft motion
is imparted to drive wheel 15° by means of a bevel gear 16 fixed to said shaft and
engaging a bovel gear 17 fixed to the shaft of wheel 15. Drive wheel 15 is driven
by a bevel gear 18 fixed to shaft 13 meshing with a bevel gear 19 fixed to the shaft
of drive wheel 15. Drive wheel 15° is driven by means of a bevel gear 20 fixed to
the shaft of drive wheel 16 which gear meshes with a bevel gear 21 fixed to the shaft
of drive wheel 15. From this arrangement of gearing the rotation of the shaft 13
in the proper direction will cause all the drive wheels to turn in the same direction,
drawing the four bands downward through the mold from over the guide wheels.
In the operation of casting by my improved apparatus, the proceeding is as
follows:-
The bands having been previously coated with graphite, soot, or other suitable
material to facilitate the separation of the ingot, the space between these bands
at a point within the mold near its lower end is closed by means of a plug of iron,
asbestos or other suitable material, as indicated by dotted lines at 22, Figure 1.
Molten metal is then poured in at the top of the mold between the bands in a
continuous stream and when the metal rises in the mold to about the point
indicated by dotted lines at 23 the drive wheels carrying the bands are set in motion
and the bands slowly move downward through the mold, their speed being so
regulated that the tendency of the metal to rise will be counteracted by the down-
word movement of the body of metal, thereby maintaining the level of the metal
at practically the same point within the mold. Water or other cooling medium
being circulated through the chambers in the mold the outer portion of the molten
metal will instantly cool and harden. By the time a given portion of the ingot
has reached the lower end of the stationary mold its walls will have become
thick enough to withstand the pressure of the molten metal above and the casting
will issue from the hands at the lower end of the mold as a continuous bar, free
from hollows, boles or other imperfections. The casting or ingot may be further
sprayed to cool it as it leaves the bands or it may be passed through a second hollow
mold or casing 24 and there subjected to the action of a cooling medium circu-
lated through this casing. At any suitable point beyond the mold the casting as
it issues therefrom may be severed into lengths for the market.
The casting produced in the mauner described will be free from the usual
shrinkage cavities so common in ingots east in a stationary mold, the weight of the
overlying body of soft metal in my apparatus as it is introduced into the mold
being exerted vertically on account of the vertical position of the mold insuring a
solid and homogeneous casting.
It will be observed that in my apparatus the metal is wholly surrounded by the
bands and they being thin the heat is rapidly withdrawn by the cold surrounding
fixed mold, the result being a rapid cooling and hardening of the casting.
While I have described and illustrated a mechanism embodying my invention in
a practical form and one which I prefer to adopt, it will be understood that the

page_text: invention is not limited to this particular form. For instance, the fixed mold
may be of other forms in a cross section, as triangular or as shown in Figure 4
the corners of the mold may be rounded. In this case, while the bands will not
meet at their edges, the limited uncovered space of the mold at its corners will
not interfere to any material extent with the advance of the body of metal within
the bands as the bands are moved through the mold. Further, it is not necessary
that the bands be endless for, as shown in Figure 5, they could be connected at
their ends to rollers 25 and 26 and adapted to be wound on the roll 26 from the
roll 25.
It is important that the bands be maintained under such tension that they will
pass closely and flatly against the faces of the mold. I ensure this result by
means of weighted levers C pivoted to the standards adjacent to the guide wheels
as at c and having their inner ends extending beneath depending extensions c¹
on the bearing blocks of the guide rollers. These levers will force the blocks
upward in their guides with a yielding pressure and will hold the bands tightly
against the sides of the mold. In order that the bands may be held flatly against
the drive wheels to ensure their movement by the wheels, I provide each wheel
with a pressure roller D mounted on the end of an arm & pivoted at its inner end
to the standard. The contact of the roller with the band is maintained and con-
trolled by a connecting rod jointed to the arm and to the standard and having
a turn buckle or adjusting nut to regulate the pressure of the roll.
By arranging the mold in a vertical position with the bands passing downward
vertically through the opening therein as in the apparatus described, peculiar
advantages will result when employed for casting steel ingots, in that there will be
no liability of the ingot cracking, inasmuch as it passes in a straight line while be-
tween the bands, the latter moving with it and not relatively to it. This is of great
importance when is considered the great care required in handling ingots at the
tender" stage of their formation. Unless handled with the greatest care the skin
or wall of the ingot will crack. In my apparatus the casting is not subjected to any
lateral strain or bending action, nor is there any relative movement of the mold
and ingot inasmuch as the lining of the mold follows the ingot in a straight line,
the lateral separation of the bands from the ingot not being of such nature as to
cause any injury to the same.
"
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. The combination with a fixed mold or casing provided with a vertical opening
therethrough from end to end and with a chamber or chambers surrounding said
opening, of thin metallic bands extending through the opening in the mold and
flatly against its interior sides and jointly wholly covering the same, means for
moving the bands downward through the mold and means for circulating a
cooling medium through the surrounding chamber.
2. The combination with a fixed mold or casing provided with a vertical opening
therethrough from end to end of rectangular form in cross section and with a sur-
rounding chamber or chambers, of four thin metallic hands extending downward
through said opening and flatly over the four interior sides of the mold, means
for moving said bands downward through the mold, and means for circulating a
cooling medium through the surrounding chamber.
3. The combination with the fixed mold or casing provided with an opening
therethrough from end to end, of the band extending through said opening and
the rolls over which said bands pass, said rol's having their peripheral surfaces
situated laterally beyond the respective interior sides of the mold; whereby the
rolls will have a tendency to maintain the close contact of the bands against the
interior sides of the mold.
4. The combination with the fixed mold or casing provided with a vertical open-
ing therethrough from end to end forming flat interior faces rounded or curved

page_text: outward at the upper end of the mold, of the bands passing downward through
the mold and closely over the flat interior surfaces thereof; whereby the introduc-
tion of the molten metal into the upper end of the mold between the bands is
facilitated.
Dated this 29th dar of November 1897.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.