Improvements in Process of and Mold for Casting Steel Wheels.
Year: 1891

page_text: Date of Application, 12th May, 1891-Accepted, 13th June, 1891
COMPLETE SPECIFICATION.
Improvements in Process of and Mold for Casting Steel Wheels.
I, WILLIAM GORDON RICHARDS, of No. 536 Broadway, Boston, in the County
of Suffolk, and State of Massachusetts, United States of America, Engineer, do
hereby declare the nature of my invention for IMPROVEMENTS IN PROCESS OF,
AND MOLD FOR CASTING STEEL WHEELS, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement :---
In the drawings accompanying and forming a part of this Specification―
Fig. 1 is a plan view of an unfilled mold embodying features of my invention.
Fig. 2 is a vertical section through the unfilled mold.
Fig. 3 is a similar view showing the mold after it has been filled, and illustrating
certain features of the action of the metal in the mold.
Fig. 4 is a similar view showing the mold after the casting operation has been
completed.
Fig. 5 is a diagrammatic view similar to a portion of Fig. 4, and illustrates
the action of the elastic abutment.
Fig. 6 is another diagrammatic view further illustrating that feature of the
process.
Fig. 7 is a diagrammatic view illustrating the closing stage of the mold-filling
operation, or the "feeding" of the casting.
Similar characters designate like parts in all the figures.
The mold herein shown is adapted to be used for casting car-wheels by the
method hereinafter described.
The flask, as herein shown, consists of the bottom-board, the nowel-frame, the
chill, the cope-frame, and a pouring-head connected to the flask below the chill,
and whose channel continues along the lower part of the mold underneath the
wheel space therein. The nowel-frame, the chill, and the cope-frame, are all sub-
stantially circular in plan view. The mold consists of the nowel B, the chill D set
on the nowel and its frame, and the cope C set on the chill substantially as
indicated in the drawings. The pouring-head E is attached to one side of the mold
at or near the base thereof, and extends to a point somewhat above the top of the
mold, substantially as indicated in Figs. 2 and 3. The channel 6 of the pouring-
head extends downward and connects with the horizontal runner 7 formed in the
nowel underneath the mold, as indicated in Fig. 2.
From the horizontal runner 7 one or more short connecting channels 8 extend
upward into the lower end of the hub space 9, through which channels the metal
enters the mold. Over the hub space of the mold are formed a series of vents, 4,
usually two or more in number, for the escape of air and gases from the mold and
to provide for overflowing the metal when this is desired. Other similar vents, 5,
are formed at suitable distances apart over the rim space 10 of the mold for a
similar purpose. The usual "arch-core," F, is provided to form the space between
the upper and lower plates of the wheel, and the center-core, G, is provided for
making the usual central opening in the hub. The arch-core divides that part of
the mold space surrounding the hub space into the front plate space 11 and the
back plate space 12, as shown in Fig. 2. That part of the mold surrounding the
arch-core between the rim space and said arch-core is designated as the single plate
space.13.
The horizontal runner underneath the mold is extended beyond the vertical
passage or passages 8, to form the catch-chamber 14, constituting a receptacle for
the first-inflowing metal and to catch the debris and "wash" of the pouring-head
surfaces, always accompanying the first influx of metal; also to hold at a high
temperature a body of metal serving as a heat-reservoir for prolonging during the

page_text: atter part of the pouring operation the fimidity of the metal in the aforesaid
vertical connecting passage or passages.
In the process of casting the wheel, the molten steel is steadily poured into the
head E, Hows rapidly through the channel or runner 7, and enters the mold through
the short vertical channels 8, at the lower end of the hub space 9.
The wheel W, shown in the mold in Figs. 3 and 4, is a car-wheel of the double-
plate variety, having the rim R, the hub H, the front plate 11, the back plate 12
and the single plate 13", which may be considered as a continuation of the two
plates 11" and 12", for joining these two plates and the rim. It is found to be
essential to the successful use of steel wheels in railway service that the entire
wheel, but more especially the hub thereof, shall be substantially sound throughout,
and free from porosity, and of shrinkage or other internal cavities. It is one of the
principal objects of my invention to furnish a mold adapted for casting steel car-
wheels of that character.
The molten metal being run into the mold through the runners underneath
the mold, heats the walls of the runner to the highest degree of any part of the
mold, so that on the cessation of the pouring the hottest metal in the mold is
in the runner below the wheel, from whence it is drawn into the hub through
said passages 8 by the contraction of the metal contained in the hub part of the
mold during the cooling of the casting. The runner extending for a considerable
distance along close underneath the casting, is thereby prevented from being
cooled by the upward absorption of heat by the casting, thus being retained it its
excessively hot and fluid state.
Said connecting passages 8, when made, as in practice I make them, of less
aggregate area than the runner 6, give to the up-flowing metal a relatively high
velocity, whereby the metal flowing into the mold is carried well up into the hub
space, whereby the in-flowing metal is thoroughly mixed with that already in said
hub space, thus distributing the excess of temperature in the in-flowing metal more
widely throughout the metal of the hub, and promoting the uniform shrinkage
of the hub-metal immediately following the cessation of the influx of metal into
the hub space.
The short vertical columns of metal in the passages 8 being situated between
two larger masses of hot metal, and being also in a vertical position, so that the
heat of the lower mass of metal is naturally transmitted directly up through them
into the upper mass of metal, are thereby maintained in a perfectly fluid condition
a relatively long time, notwithstanding their relatively small diameter. By means
of this organization of said parts, the necessary size of said columns is reduced
to the lowest point, thereby reducing one of the objections arising from the use
in steel castings of large runners, since during the latter part of the cooling
period the metal in the casting at the junction of the runner therewith is most
nearly fluid, and being weakest, becomes porous from the shrinkage strains. By
making the large runner horizontal and connecting with the mold through short
reduced passages, and by arranging those passages vertically between the large
runner and the mold, I avoid the objection arising from the use of large runners
connecting directly with the mold, while retaining the efficiency of the larger
runner.
The horizontal runner lying immediately underneath the wheel, and being
arranged as set forth to preserve its heat for the longest practicable period, con-
stitutes a reservoir from whence the wheel draws its feeding-supply by suction
through the aforesaid vertical passages; that suction being aided by the pressure
of the metal in the pouring-head.
The large horizontal runner extends beyond the short vertical connecting
passage leading from said runner into the under side of the mold, thus forming
a chamber, 14, into which the first-entering metal is driven, carrying with it the
sand and impurities of the passage leading to the mold and retaining them there,
preventing their entrance into the mold. Also, the mass of metal beyond the
vertical passage serves as a heat-reservoir to aid in maintaining the fluidity up to

page_text: the latest possible moment of the metal in the vertical passage and in the horizontal
runner immediately below said passage for during the whole pouring operation
the hot metal passing at a high velocity through the runner to the farthermost
connecting passage, is imparting its heat by conduction to the mass in said
space 14 so that at the end of the pouring operation the temperature of said
heat-reservoir is substantially equal to that of the flowing metal itself.
Inasmuch as it is customary to use a central corc, Cr, in the mold, it is
advantageous to use a plurality of connecting passages, 8 8, instead of relying
upon a single passage, as otherwise might be done. However, the number of said
passages depends upon the shape and size of the casting to be made; in the case of
car-wheels, I use in practice two said passages, as shown in the drawing.
In order to obtain the best results, it is very desirable that the inflowing metal
shall pass along constantly in the same direction without interruption from the
beginning of the pouring operation until the feeding of the casting is complete,
with the least possible agitation.
Owing to its peculiar physical character, steel, as is well known, when cast in
pieces of much thickness, has a decided tendency to "pipe," or form internal
cavities, on the cooling of the casting. This tendency not only occurs in the
castings themselves, but also in the runners through which the steel is conveyed
into the molds. To prevent said "piping," I have discovered that the size of
runner should be reduced to a thickness less than a certain critical size which may
properly he designated as "the non-piping limit; which limit, in practice, for
steel suitable for making car-wheels, is much too small to serve as runners for
filling the mold by the old methods. By means of my present improvements,
however, said mold-filling passages may be reduced to a size below said non-
piping limit, being usually, in practice and with the kinds of steel I ordinarily use,
about one-half of an inch in thickness, but varying somewhat according to the
particular composition of the metal.
By the term "piping," as applied to the piping of steel castings, I do not refer
to the small pin-holes and cavities sometimes found throughout the mass of the
casting, but refer, instead, to those elongated openings naturally formed in the
interior of the casting after the outer surface of the casting has solidified and by
reason of the joint action of contraction and the attraction-of-cohesion, whereby
metal in the interior and most fluid part of the mass, as congelation sets in, is drawn
outward to supply the shrinkage just within the aforesaid surface of the casting.
In the operation of pouring the mold, the highly heated molten steel is poured
into the pouring-head E, and follows down through the large runner in a full stream
and at a rapid velocity due to the height of the pouring-head, and flows along the
horizontal part of the main runner until it strikes abruptly against the abutment
formed at the terminus of the large runner. During this passage and at the first
touch of the hot metal against the cooled surfaces of the mold, there is formed a
thin coating or scale adhering to the granular material of the mold and constituting
a heated metallic tube within which the molten steel afterward continues to flow
during the pouring operation. At the mold-filling passage or passages 8, said
metallic tube or casing, (there being a space at said passage rather than a con-
tinuous surface,) is formed thinner or with a break therein. On the metal striking
the abutment beyond said passages, there occurs a violent reaction in the nature of
a blow, whereby the metal in the large runner contiguous to said passages is forcibly
impacted between the metal against the abutment, as 15, and the on-coming heavy
stream from the pouring-head. The effect of this reaction is to impart a sudden
and violent pressure to the metal immediately at the said mold-filling passages,
whereby the aforesaid scale or tube (when the same has formed at said passages) is
burst through, and whereby the metal then in the large runner at said passages is
violently driven at a high velocity through the passage into the mold. By this
method of inaugurating the mold-filling current or stream of metal, (by which term
I designate the current in the aforesaid passages 8,) the highest attainable velocity

page_text: of said mold-filling currents is obtained, whereby the cross-sectional area of said
passages may be reduced to a minimum.
By means of the construction here described, the metal at said point is driven in
directions which are resultants of the forces of action and reaction. This is
indicated in the diagrammatic Fig. 6, where the arrow a indicates the direction of
the on-coming stream of metal, and, of course, of the momentum of said stream;
while the arrow indicates the direction of the resistance caused by the aforesaid
abutment. These two forces co-act to drive the metal laterally, as indicated by
the arrows and d, at the point of least resistance; which point occurs at the inter-
section of the branch runner 8, as shown.
By this method of casting, the first metal entering the large runner suffers the
greatest chilling of any metal entering the mold during the pouring operation, since
it traverses the entire length of the large runner and thus comes directly in contact
with the largest area of cold mold-surface. By reason of the cooling of said first-
inflowing metal, this metal becomes unfit for, or incapable of, entering the mold
through a sufficiently small mold-filling passage, and hence, according to my present
invention, said cooled first-inflowing metal is carried beyond said inlet-passages,
and is detained from entering the mold, being utilized for effecting the impact above
described by which the mold-filling current is inaugurated. After the pouring
operation is begun and said mold-filling current or currents are established, the
cooled metal first delivered into the large runner beyond said mold-filling currents
is gradually re-heated, so that at the end of the pouring operation it becomes
substantially uniform in temperature with other parts of the runner, this re-heating
taking place gradually by reason of and from the action of the current existing in
said runner and passage-ways.
27
At the moment the first-inflowing metal reaches the terminus of the large runner,
the elongated mass acquires a considerable momentum, and may be said to act on
the principle of the well-known" water-ram to drive the metal laterally through
the small runners with a relatively great force. This feature will be readily under-
stood when it is observed that the aggregate mass of the heavy fluid metal in the
large rummer is very considerable, and the velocity, owing to the height of the
head E, is also considerable, thus furnishing ample means for causing a reactionary
effect of high intensity. If the walls of the chamber 14 immediately before the
abutment 15 be sufficiently vented, the air contained in said chamber or pocket
will escape before the on-coming current of metal, and the metal be driven or
impacted directly against said abutment, as indicated in Fig. 4, so that the reaction
will be sudden and correspondingly intense. But, in practice, not only is it
desirable to secure the described reaction, but also to prolong the reactionary effect
until the resulting mold-filling current is thoroughly established at a high velocity;
this object is secured by making said chamber or pocket 14 only slightly vented or
pervious, so that on the approach toward the abutment 15 of the large stream of
metal, some air, (or mingled air and gases,) is temporarily caged or shut in the
chamber 14, to serve as an elastic or "cushioned abutment forming a spring
whose effect is to prolong the reactionary effect by driving back somewhat the body
of metal in the chamber, thus for the moment supplying the mold-filling current or
stream from both sides of the small runner 8, as indicated by the curved arrow at e
Fig. 5. This operation being, in point of time, very quickly carried on, there is
then no further use for the air constituting said cushioned abutment, and said air
is gradually exhausted through the pervious walls of the mold, or through
vent, as 16, Fig. 6. By means of this process of filling the mold, it is made
practicable to use a mold having the inlet-passages of less thickness than the "
piping limit," without causing congelation of the steel within those passages before
the mold-filling current is fully established therein.
a small
non-
For an explanation of the special utility of using mold-filling runners of a size
less than the normal non-piping dimension, it is necessary, as I understand it, to
take into consideration the peculiar behaviour of steel in the operation of casting,

page_text: as modified by the necessary "feeding" of the mold after the same is first filled.
It is well understood that steel, when cast, has at a certain moment in the cooling
thereof a sudden and relatively great shrinkage, which it is supposed takes place at
about the point of temperature where congelation sets in. The result of this sudden
action must necessarily be either to pipe the casting or to draw together the outer
shell thereof, it being understood that, some moments before general congelation
sets in, a comparatively strong shell is formed by cooling over the surface of the
casting, excepting at the point where the casting is being fed, this point being still.
molten by reason of the continued inflow of hot metal through the mold-filling
runners. The piping effect, or tendency, is strongest, as is well known, at the
interior of the mass, so that by reason of the gradual cooling from the outside
towards the interior, the most effective feeding of the casting can be attained only
by the highest velocity practically attainable of the feeding current, this being a
prolongation (in point of time) of the mold-filling current through the outer part of
the casting into said interior. If, now, the runner joining the casting be of relatively
large size, the velocity of the feeding current is reduced, and there is formed therein
a tendency to pipe on cooling, the piping of the rummer following into the casting
and joining the piping in the interior thereof. This results in forming a defect, or
break, in the continuity of the surface of the casting, thus weakening the whole
structure, besides directly antagonizing the solidifying of the interior of the casting,
by reason of a counter-suction produced by the internal shrinkage and consequent
suction within the runner itself. By reducing the runners below the non-piping
limit, the congelation, when it finally extends to the runner, seals over and closes
the outer part or shell of the casting at the point where the runner enters the same,
thus forming an unbroken and perfect surface for the casting, and so closing the
exterior shell of the casting that the internal shrinkage and suction has the effect
of drawing together the shell for closing the interior pipe which otherwise would
naturally Torm in the interior of the casting. But, as above pointed out, rummers
small enough to produce the peculiar effect required are impracticable for use
unless means be had for successfully inaugurating the mold-filling current, which
according to my present improvements is attained, as hereinbefore explained, by
means of a reactionary effect whereby the metal first entering the runner is not
delivered into the mold, but is utilized for other purposes, and whereby the mold is
first filled by metal following the first-inflowing metal.
This feature is illustrated in Fig. 7, wherein the light-shaded part 17 designates
the region of fluid metal at the moment before closure by congelation of the feed-
passage at Sª. After the mold is completely filled and the exterior of the casting
is solidified, as indicated by the dark shade at 18, Fig. 7, congelation gradually
extends towards the interior of the casting, and also gradually extends inwardly
throughout the main runner and through the mold-filling runner: the contraction
due to congelation being supplied by the current through the vertical runner 8, as
indicated by the light-shaded passage at 19, Fig. 7 of the drawing. As the
congelation extends close to the center of the casting, leaving but a small part,
as 17, remaining fluid, the contraction of the metal becomes more rapid, producing
a suction increasing the speed of the feed-current 19, which operates, by reason of
its considerable velocity, to keep open the passage 8" through the lower surface of
the casting and to delay the closure thereof until the latest possible moment. The
feed-current 19 being thus accelerated, is maintained as described until it becomes
relatively very small and is reduced to a size less than the normal size of a globule
of congealing steel, so that on the final closure or congelation of the metal at 8" no
pipe can form, but the surface is closed by cohesion and left perfectly sound. After
this, the final shrinkage of the metal in the hub of the wheel goes on gradually and
normally until the metal is cooled in a solid form.
In the double-plate style of wheel shown in the drawings, there is normally in
the hub two piping-lines, one at the juncture of the upper plate and hub, and the
other at the juncture of the lower plate and the hub. The upper pipe is naturally
and readily filled by the up-flow of hot metal in the interior of the hub, and for the

page_text: reason that the upper plate, 11, of the wheel cools most quickly, owing to the rapid
radiation of heat from the upper side of the mold while the lower plate remains
molten. The lower pipe is filled as above described by a small accelerated current
from the main runner, which is kept supplied from the pouring-head. The small
runner, or mold-filling passage 8, should be set vertical to the normal piping line
of the hub, so that the forced stream of metal is delivered directly to the point
of greatest suction, as best shown in Fig. 7.
It is well understood by those acquainted with this art that the functions of a
car-wheel are many and diverse, one of the most essential being that the hub shall
safely resist the enormous bursting strains caused by the forcing in of the axle
under the hydraulic press; which strains, in the case of steel wheels, result from
a pressure of about thirty to fifty tons longitudinally of the axle. This requirement
necessitates an excessively strong hub, which in turn requires a thick hub of sound
metal. But an extra thick body of metal at the hub is in itself a detriment to
the wheel in other respects, since it introduces variations in the shrinkages, and
increases the naturally great tendency to the forming of internal shrinkage cavities.
To overcome these obstacles, while retaining a relatively thick hub; to maintain
as long as possible the highest degree of heat and fluidity in the hub; and to fill
the mold with the least agitation of the inflowing metal, are, therefore, among the
chief objects of my present improvements.
In the process of casting the wheel, the molten steel is steadily poured into the
head E, flows rapidly through the channel or runner 7, and enters the mold
through the channels 8, at the lower end of the hub. At this stage of the
process, (referring to Fig. 3,) the metal is flowing outward through the lower
plate space 12, as indicated by the arrow. As the process proceeds, the metal fills
the lower plate space, enters the rim space, and returns through the upper plate
space, toward the upper end of the hub. Here the metal in said upper plate space
meets the metal rising in the hub space, and is united by admixture. Following
this, the metal continues to rise in the hub, thus furnishing more metal and more
heat to the thickest portion of the wheel, and thereby feeding both the lower and
the upper plates during the early period of their shrinkage. And during this
later portion of the operation all the metal of the hub (except, possibly, a very
thin surface scale,) ascends together, thereby bringing to the junction of the lower
plate and the hub a fresh supply of relatively un-cooled metal at the very latest
moment of the process; which fresh supply forms a new admixture with the metal
of the inner edge of the plate, and thus continues to the latest possible moment
the conditions most favorable to the proper shrinkage and final cooling of the
wheel.
By pouring this form of wheel from below as set forth, the highly heated and
fresh metal is utilised most effectively for re-heating the metal already in the hub,
owing to the ascendant power of the heat itself under such circumstances. By
this means both the temperature and fluidity of the entire hub is unified, and is
maintained throughout at the highest possible point until the pouring operation
is entirely completed. By this means, also, the rim during its early cooling stages
is most evenly and effectively "fed" through the plate the fluidity of the plate is
better maintained; and at the close of the pouring operation, the hub itself is left
in the most favorable condition for continuing said " feeding and for its own
shrinkage.
When the metal begins to fill the rim space 10, the first effect of the chill D is
to rapidly abstract heat from the upper surface, 20, of the flange 21. This reduces
a layer of said metal to a temperature where it regains its cohesion and strength.
As the mold continues filling, this cohesive surface-layer widens and thickens, so
that by the time the mold is filled said cohesive layer constitutes a surface-ring of
relatively great strength which ring being flanged by the portion on the lower
edge thereof, is thereby given the cross-sectional form of an angle-iron, (as between
lines ab, Fig. 3.) and thus greatly strengthened in its resisting power. Owing to
this outer resistance-ring created thus early in the operation of filling the mold,

page_text: and to the substantially two-fold shrinkage peculiar to steel when made into
castings, the earlier shrinkage of the interior parts of the wheel-casting is strongly
opposed by said ring, thus creating two tendencies: first, to draw the interior
metal outwardly, by attraction of cohesion, at the expense of the thickness;
second, to form interior shrinkage cavities. To secure a sound wheel, it is necessary
to favor the first, and to resist the second of said tendencies, this being done in my
improved process as follows:
Reference has been made to the ascendant power of heat, whereby, at the end
of the pouring, the heat of the hub-metal is unified or equalized. This ascendency,
however, operates in the plates, and earlier in the said operation, with a different
effect, which is indicated in Fig. 3 by the darker shading at 22 22.
The cope C
being freely vented and also absorbent of heat, the metal of the upper plate 11"
becomes stagnant or non-flowing earlier than the metal of the lower plate 12, and
also before the metal of the rim at R has become set, or much shrunken. This leaves
the metal of the lower plate 12" still fluid, and with an outwardly flowing movement
into the single plate space 13, and through said space 13 into said rim space,
whereby said rim is effectually "fed" until the very latest moment of the pouring,
and a sound rim thus obtained. While this feeding" of the rim is going on, the
outward movement of the lower plate metal delays the setting thereof, and at the
same time said movement is forcibly promoted by the pressure of the inflowing
metal, which pressure is due to the height of the pouring-head C. On the complete
filling of the lower plate space, and the stagnation or setting of the metal therein,
the inflowing from below of the hot metal still continues to effect the aforesaid
re-heating of the hub-metal and the re-admixture thereof with the plate junctures,
whereby the fluidity of the entire hub is maintained for the longest possible time,
and the feeding of the now rapidly shrinking lower plate is longest continued.
By the old methods of making this class of wheels, there was a great tendency
to form a shrinkage-space within the rim of the wheel; which tendency is sub-
stantially overcome by the more efficient feeding of the rim due to my
improvements.
Another valuable result obtained by making the wheel-casting with the flange 21
below the chill, is that by this means the inner (upper) surface of said flange is
more effectually cooled, toughened, and shrunk to a very large degree, before any
shrinkage strains are thrown thereon by the other parts of the casting, so that said
flange-face is obtained free of checks and defects due to shrinkage strains, thus
adding materially to the durability and value of the wheel.
During the later stages of the pouring operation, the plate-and-rim juncture on
the dotted line, Fig. 3, and also the plate juncture on the dotted line, Fig. 3,
are through-flowed by a current represented by the arrow, said current passing
through the lower plate 12 and through the single plate 13 into the rim of the
wheel. This through-flowing operation takes place during the solidification and
contraction of the upper plate 11", traverses said junctures and thereby supplies the
shrinkage of said plate and overcomes any tendency which would otherwise exist
for the contracting plate to separate from the exterior parts of the wheel. In
practice, it is desirable that the through-flowing should be carried sufficiently far to
cause an overflow of the rim at the passage 5. In passing from the single plate
into the upper part of the flange, said through-flowing current reaches to the pipe-
forming region of the flange and thus prevents piping therein. In relation to this
feature of my improvements considered as a sub-process therein, the lower plate
space of the mold constitutes a runner through which to fill the single plate space
and the rim space of the mold, and through which to feed said portions of the
casting after the congelation of the upper plate, this congelation being indicated, as
before mentioned, by the darkened shading at 22, Fig. 3. The process of making
castings by through-flowing the plate-and-flange juncture during the contraction of
the plate is described and claimed in a separate application for Letters Patent of
Great Britain which I have filed of even date herewith. The process hergin

page_text: described of casting a double-plate wheel by through-flowing the two plate
junctures simultaneously during the contraction of the upper plate, is in the nature
of an improvement on the process described and claimed in the aforesaid
application.
Two stages of the mold-filling operation are shown in Figs. 3 and 4. In Fig. 3
the metal is shown overflowing the hub-vents 4, while the rim in just filled, the rim
vents not yet being overflowed. At this moment during the pouring operation, the
workman suddenly checks the overflow at the hub-vents, which may be done by
means of a chill, as 23, shown in said Fig. 3, placed on the outflowing metal over
said vents this chill, by suddently abstracting heat from the overflowed metal,
instantly checks the overflow, so that after a very brief time the chill may be
removed. Later in the pouring operation and as a sub-process therein, the rim-
vents are suddenly checked, thereby bringing the full pressure of the head of metal
onto the rim for the feeding of the same after the plate spaces and hub spaces are
fully filled. For checking the rim-vents, the same chill 23 may be used as for the
hub-vents of, ᎥᏝ more convenient, a separate smaller chill, as 24, may be used, the
several rim-vents being checked in quick succession.
Having now particularly described and ascertained the nature of my inven
tion, and in what manner the same is to be performed, I declare that what 1
claim is
1. The process herein described for making plate-and-rim steel wheels, which
consists in filling the mold from below, the rim space being filled through the plate
space, and overflowing the rim during the solidifying of the thread surface, substan-
tially as described:
2. The process herein described for making double-plate steel wheels, which con-
sists in filling the mold from below, the rim being filled through the plate space,
and overflowing the rim during the solidifying of the thread surface and simul-
taneously with the congelation of the upper plate, substantially as described. "
3. The process herein described for making double-plate steel wheels, which
consists in filling the mold from below and simultaneously overflowing the rim and
hub during the solidifying of the thread surface and the congelation of the upper
plate, substantially as described.
4. The process herein described for making double-plate steel wheels having a
single plate intermediate to the rim and the double-plates, which consists in filling
the mold from below and continuing the pouring to simultaneously through-flow the
plates juncture and the plate-and-rim juncture during the congelation and contrac-
Lion of the upper plate, substantially as described.
5. In a mold for casting steel car-wheels, the combination with a part formning the
outer wall of the mold space, and with the cope having overflow passages over the
rim space and over the hub space, of the nowel having the enclosed main runner
extending from one side of the mold along under the mold space to a point beyond
the hub space thereof, mold-filling passages branching vertically from the main
runner to the under side of the hub space, and the pouring-head connecting with
the outer end of the main runner, the whole being organized substantially as shown,
whereby the mold may be filled to overflowing and the casting fed by a continuous
and unbroken stream of metal, substantially as described.
6. In a mold for casting steel car-wheels, the combination with a part forming
the outer wall of the mold space, and with the cope having overflow passages over
the rim space and over the hub space, of the nowel having the enclosed main
runner extending from one side of the mold along under the mold space to a point
beyond the hub space thereof, mold-filling passages branching vertically from the
main runner to the under side of the hub space from points beyond the terminus of
the main runner, said main runner also extending beyond the mold-filling passages
Lo form the catch-chamber, and the pouring-head connecting with the outer end of
the main runner, the whole being organized substantially as shown, whereby the

page_text: mold may be filled to overflowing and the casting fed by a continuous and unbroken
stream of metal entering the mold under pressure of a reaction after the first-
inflowing metal has been pocketed in said chamber, substantially as described.
7. That improvement in the art of making steel castings which consists in running
the molten metal in a full stream through a runner located below and adjacent to
the mold space, and against a reactionary abutment, and flowing the metal upward
into the mold from a point before the abutment under pressure of the reaction and
through a relatively small mold-filling passage, the mold-filling current being taken
from the main current at a point back of the first-inflowing metal, and the first-
inflowing metal being detained from entering the mold, substantially as
described.
8. That improvement in the art of making steel castings which consists in running
the metal through a main runner adjacent to the mold space and against an air-
cushioned abutment, flowing the metal from the main runner into the mold from a
point before said cushion under pressure of the reaction thereof, and exhausting the
air-cushion during the filling of the mold, substantially as described.
9. The improved mold herein described for making steel castings, consisting in
the combination with parts forming the top and sides of the mold space, of the
nowel having a horizontal main runner extending beyond the mold-filling passage
connecting said main runner with the mold space, said main runner extension being
slightly vented or pervious, and adapted to retain air for cushioning the first influx
of the metal, and to exhaust the air during the pouring of the mold, substantially
as described.
10. That improvement in the art of casting steel car-wheels which consists in
forming the mold with top-vents arranged in two sets, one set being over the hub and
the other over the rim, pouring the mold to overflowing, and checking the hub-vents
after the overflow, whereby an additional impetus is given to the flow of metal
toward the rim, substantially as described.
11. That improvement in the art of casting steel car-wheels which consists in
forming the mold with top-vents arranged in two sets, one set being over the hub
and the other over the rim, pouring the mold to overflowing, checking the hub-vents
after the overflow, and continuing the rim overflow after the checking of the hub
overflow, substantially as described.
Dated this 19th dov of Nov 1891
S. S. BROMHEAD,
97, Newgate Street, London, E.C., Patent Agent.