Improvements relating to the Manufacture of Rolled Forgings and to Apparatus therefor.
Year: 1889

page_text: Date of Application, 27th June, 1889
Complete Specification Left, 27th Mar., 1890-Accepted, 17th May, 1890
PROVISIONAL SPECIFICATION.
[Communicated from abroad by GEORGE FREDERICK SIMONDS, of Fitchburg,
Massachusetts, United States of America, Engineer.]
Improvements relating to the Manufacture of Rolled Forgings and
to Apparatus therefor.
I, RICHARD COPLEY CHRISTIE, Chairman of The Simonds Steel and Iron Forging
Company, Limited, of City Bank Buildings, Queen Victoria Street, in the City and
County of London, do hereby declare the nature of this invention to be as
follows:-
This invention relates to the forging of articles which are polygonal, fluted,
serrated or of any desired shape other than circular in transverse section, by rolling
the bar to be forged between dies which move in opposite directions.
In the specification of Letters Patent dated June 9th, 1885, No. 7028 are shown
and described dies for forging metal articles circular in transverse section, the said
dies being moved in opposite directions with the metal bar or blank to be shaped
rotating about its axis between them.
The said dies have reducing and spreading surfaces by which the metal is spread
or forced axially along the blank that is being rolled, thus bringing the said blank to
the desired shape in longitudinal section.
In the specification of former Letters Patent dated 9th January A.D. 1886,
No. 396, there are described generally a method of and apparatus for manufacturing
rolled metal articles which are polygonal in transverse section or which have grooves
or projections or both grooves and projections extending parallel with or inclined to
their axes.
The object of the present invention is to provide improved methods of and apparatus
for forging by rolling, articles of various forms other than circular in transverse
section.
These methods and apparatus may be used, for example, for producing gear-wheels
or pinions or articles with fluted surfaces or of polygonal form or of other shapes
that may be suggested, which although non-circular are usually substantially
symmetrical to the axis of rotation of the object in the process of forging.
The dies for producing such articles or objects in accordance with one part of the
present invention have raised forming surfaces; and reducing and spreading surfaces,
extending diagonally to the line of movement of the die, and standing obliquely to the
plane of the die, and above or between the said spreading and reducing surfaces, the
forming surface of the die is made with raised portions and depressions which correspond
to, or as it may be called, gear with the elevations and depressions of the surface of
the object being rolled.
If. for example, the object to be forged is a toothed pinion, the forming surface of
the die will be substantially that of a rack which would gear with such a pinion; if
the surface of the article to be rolled is a polygon, the forming surface of the die is
waved or scalloped in vertical longitudinal section.
The relation of the reducing and spreading surfaces to the forming surface of the
die is such that the metal blank is acted upon first at one point on its length and is
rolled to the desired shape in transverse section for a short portion of its length, and
then, as it continues to rotate between the dies, the surplus metal is spread or forced
axially along the blank, lengthening the portion that is brought to the proper shape,
until finally the desired shape is imparted to the entire length that is to be
shaped.
The base or body of the die may have a plane surface, and the co-operating pair
of dies are arranged one over the other with the bed-portions separated from

page_text: one another by a distance about equal to the diameter of the bar or blank to be
rolled.
From the surface of the bed-portion of the die are raised the spreading and
reducing surfaces which incline upward from the surface and converge towards one
another in the direction in which the die moves, so that they meet at the point where
the dies will begin to act on the cylindrical bar or blank in the space between
them, substantially in the manner described in the aforesaid former specification
No. 7028.
The said reducing and spreading surfaces are provided with teeth or corrugations
to engage with the bar and ensure its rotation. The said surfaces when they begin
to act on the bar reduce its diameter and at the same time spread the metal, moving
it away from the point where the dies begin to act towards the ends of the bar.
The upper or forming surface of the die, between the spreading and reducing
surfaces is, in accordance with the present invention, shaped in longitudinal section
throughout the entire length of the working part of the die in accordance with the
cross-sectional shape desired to be imparted to the forging.
By this construction, when the blank or billet has been partly rolled, it will have a
short portion of its length brought to the desired shape in cross-section, and then,
as the dies progress, the said portion that is of the proper shape is gradually
lengthened, the surplus metal that has to be displaced to bring the cylindrical blank
to the desired shape being spread or forced axially along the bar, so that, in the
operation of the dies, the shape is gradually imparted to the bar lengthwise
thereof.
By properly shaping the upper or forming surface of the dies, various cross-sectional
shapes may be imparted to the bar by this method of first reducing a short length of
the bar to the desired shape by indenting it or forming depressions around it, and
then gradually extending the said depressions lengthwise of the bar by spreading or
forcing the surplus metal along in the direction of the axis of rotation of the bar. By
properly proportioning the length and curvature of the waves of the forming surface
to the distance between the dies, the bar may be rolled to various polygonal shapes, for
example square or hexagonal, the forms that are most generally used for bolt-heads
and similar purposes; and, by dies otherwise shaped, a toothed wheel or pinion may
be forged from a cylindrical piece; or a bar with a fluted surface may be forged.
The method and apparatus are not limited to the production of any specific cross-
sectional shape of the forging.
The shapes produced by the dies above mentioned are uniform in cross-section
throughout their length; other shapes can, however, be produced. For example toothed
forgings varying in cross-section in different parts of their length. In dies for this
purpose the forming surface is cut away at the middle leaving only a narrow portion
adjacent to the spreading and reducing surfaces, so as not to interfere with the proper
rotation of the article by the portion of the reducing and forming surfaces at each
moment acting upon it. Dies of this kind may be used as parts of composite dies.
Such composite dies may be made to roll an article having a portion of its length
circular in cross-section and of any desired shape in longitudinal section and another
portion of its length fluted, toothed or polygonal; as for example a bolt-blank having
a polygonal portion or head and a cylindrical shank of smaller diameter produced by
rolling down the adjacent portion of the metal; or a toothed wheel or pinion may be
rolled in one piece with a reduced portion that may serve as an arbor, by the use of
composite dies.
According to another part of the present invention, instead of making the rolled
forgings by means of dies having inclined spreading and reducing surfaces and a
raised forming surface by which the billet or blank is first brought to the desired
shape in cross section, for a short portion of its length, and the desired shape is
gradually imparted to other portions of the bar by spreading or forcing the surplus
metal lengthwise of the bar, the forging is effected as follows, viz. :-The bar has the
desired cross sectional shape imparted to it over a considerable length by dies, which
act on substantially the whole length to be shaped, but at first impart approximately

page_text: the desired shape by making depressions around the periphery of the bar and spreading
or forcing the surplus metal towards the sides of the depressions, and into the parts
which are to be of the largest diameter in the finished forging.
The dies have raised portions or projections extending substantially the entire width
of the working surfaces of the dies, which raised portions project slightly or are of
small size at the part of the die that first begins to act on the blank, and gradually
increase in size or relief so that, as the blank rolls between the dies, the successive
larger projections act in the recesses in the blank made by the previously acting
smaller projections thereby increasing the depth or size of the recesses or reduced
portions of the forging, and throwing more metal into the projecting portions of the
forging, until finally it is brought to the desired shape in transverse section.
The raised portions and intermediate recesses of the dies can be shaped and
proportioned to the diameter of the forging, so as to produce a great variety of
cross-sectional shapes in the forgings.
The working surfaces of the said dies are of a width equal to the length of the
forging to be rolled, and the distance between the working surfaces at the end that
first begins to act on the blank, is about equal to the diameter of the blank or
billet.
The working surfaces of the said dies are provided with a series of transverse
projecting portions and intermediate recesses which are smallest or shallowest near
the end of the die that begins to act on the blank, and gradually increase in size or
relief to a point between the ends of the die; and from the said point to the end of
the die which acts last upon the blank, the said projections and the recesses between
them are uniform.
The smallest or shallowest projections first meet the blank and sink into it, spreading
or forcing the metal around the periphery of the blank, and thus tending to increase
the diameter of the blank, at each side of the place where a projection of the die acts
upon the said blank.
As the dies continue to move, the successive projections enter more deeply into
the blank, making lengthwise depressions thereon and corresponding raised portions
that enter the depressions of the dies, and the action is thus continued until all the
projections and recesses of the blank are uniform.
The spacing of the ridges or projections along the dies is proportioned to the
distance between the dies, (that is to say, to the diameter of the blank) so that
the ridges of each die will come into the depressions previously made in the blank
by the other die, and the article will thus be forged by indenting it at opposite
sides, causing it to rotate, and indenting it at different points successively around
its periphery and gradually increasing, deepening or enlarging the indentations by
successive actions at the same points.
It is obvious that, by changing the shape of the projections on the working
surfaces of the dies, the cross-sectional shape of the blank will be correspondingly
changed, and by making the said projections and recesses of the dies diagonal,
instead of at right angles to the path of the dies, the ridges and depressions on the
blank will be spirally arranged around its periphery instead of being parallel to the
axis of the forging, although the cross-sectional shape at any point may be the same
as before, depending upon the shape of the ridges and depressions of the die.
By making the projections scalloped or wave-shaped and of proper length and
curvature with relation to the diameter of the blank, or the distance between the
working surfaces of the dies, the blank will, as above mentioned, he rolled to a
polygonal shape in transverse section.
The die may be properly constructed to produce a hexagonal forging, the length
of the curved ridges or projections of the die being equal to one half the distance
between the dies measured at the recesses; and by varying the length and curvature
of the projections, with relation to the distance between them, other polygonal shapes
can be produced, the principle of operation being substantially the same as that of
producing a toothed or fluted forging by the dies above mentioned.
The ridges on the working surface of the die are sometimes made much narrower,

page_text: as well as shallower at the end where the action begins than at the end where the
action of the die is completed, so that the depressions in the blank are gradually
widened as well as deepened.
In order to ensure the proper rotation of the blank, before the projections of the
dies begin to act upon it, the working surfaces of the dies may be provided with
small teeth or corrugations which will engage with and positively rotate the blank
without producing marks that will be too deep to be obliterated by the subsequent
action of the dies, and if required the working surfaces of the dies may also be
provided with teeth along the sides of the shaping portion, which will engage with
the blank beyond the ends of the portion that is being shaped by the dies.
This construction should be adopted when the depression and elevation of the
working surfaces of the dies are not themselves sufficiently prominent to ensure the
uniform rotation of the blank.
These dies may be also used as portions of composite dies having other portions of
various kinds by which composite dies, portions of the forgings may be made
circular in transverse section and other portions polygonal, fluted or of other desired
non-circular shape.
The different parts of the said composite dies may act consecutively, or they may
act simultaneously whenever the rotation of the blank can be uniform at the different
points that are acted upon at the same moment by different parts of the die.
I prefer to arrange the dies vertically and to make the platens which carry the
dies adjustable relatively to each other instead of making the dies adjustable upon
the platens, for the purpose of regulating the distance between the dies and bringing
the dies exactly opposite each other.
1 provide for very accurately adjusting the rollers which support the dies during
the forging operation, so that the platen-guides may be relieved of pressure and will
merely serve to direct the dies and platens in their up and down movement.
I accomplish the desired results as follows, viz. -I mount upon the bed or base
of the machine two heads on which are formed or fixed the platen-guides; one of
these heads is adjustable towards and away from the other head; the latter is
adjustable in a direction parallel to the axis of a bar or blank when in its proper
position in the machine. This adjustment may be effected by means of a screw passed
through the bed of the machine, or by other convenient means. The bearings of the
shafts for operating the platens are movable in suitable guides and have combined
with them means for accurately adjusting the said bearings towards or away from
the platens. A convenient device for this purpose comprises a cam or excentric which
is formed or fixed on a suitable shaft and bears against the bearing. Worm-wheel
teeth are formed on this shaft and a worm is geared with the said teeth and is so
arranged that it can be conveniently rotated to adjust the bearing as above
mentioned.
Dated this 27th day of June 1889.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements relating to the Manufacture of Rolled Forgings
and to Apparatus therefor.
4
I, RICHARD COPLEY CHRISTIE, Chairman of The Simonds Steel and Iron Forging.
Company, Limited, of City Bank Buildings, Queen Victoria Street, in the City and
County of London, 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 5
and by the following statement :-
This invention relates to the manufacture of rolled forgings and to annaratus

page_text: shown and described a machine provided with dies which move in opposite directions.
for forging metal articles circular in transverse section, the metal bar or blank to be'
forged being rotated about its axis between the said dies. These dies have specially
formed surfaces by which the surplus metal is spread or forced axially or longi-
tudinally along the blank which is being rolled, thus bringing the said blank to the
desired shape and dimensions.
In the Specification of former Letters Patent dated 9th January A.D. 1886,
No. 396, there is described a method of producing articles which are non-circular in
transverse section, that is to say, polygonal, fluted and similarly shaped articles, by
rolling the metal bars or blanks between dies provided with alternate projections or
ridges and grooves or indentations corresponding to the grooves and projections to be
formed in or upon the metal bar or blank.
The object of the present invention is to provide in a more efficient manner than
beretofore, for the forging of polygonal, fluted and serrated articles, and of other
articles which are non-circular in transverse section, such as gear-wheels or pinions
or other articles with toothed peripheries.
My said invention comprises an improved method of manufacturing such articles
by means of dies which, in the operation of the machine, first impart the desired
shape or configuration to a portion of the bar or blank by forming around it a series
of indentations or depressions, and then gradually lengthen the said indentations or
depressions or extend the same lengthwise of the bar or blank, at the same time
spreading or forcing longitudinally outwards or towards the sides of the dies, the
surplus metal thu's displaced, until a forging of the desired shape or configuration is
produced.
My said invention also comprises an improved method of manufacturing the said
polygonal, fluted, toothed or similarly shaped articles by forming around the blank a
series of indentations or depressions of the required length, and then gradually.
enlarging such indentations or depressions by repeated pressure therein and by
spreading or forcing the displaced metal around the blank to form thereon projections
or ridges between the said indentations or depressions.
The dies for producing forgings according to the method first above mentioned are
constructed with diverging raised spreading surfaces similar to those described in the
said former specification No. 7028, and between the said spreading surfaces the dio is
provided with alternate raised portions, ridges or projections and depressions, which
correspond to the elevations and depressions to be formed on and in the metal bar or
blank, and some of which may be said to gear witli the elevations and depressions
formed by the preceding ridges and depressions of the die.
The dies for producing the forgings according to the second method above
mentioned are so constructed that they will, throughout the rolling operation, act
upon the bar or blank over a considerable length thereof, and, in so'ne instances, over
the entire length thereof to be shaped, at first imparting approximately the desired
shape by making shallow depressions around the periphery of the bar, and then
gradually enlarging these depressions, at the same time spreading or forcing the
surplus metal transversely from the centre towards the sides of the said depressions,
and thus 'forming the projections or ridges between the said depressions. For this
purpose, the dies are made with raised portions or projections which extend across the
die substantially throughout its entire width, either at right angles to the path of
movement of the die or diagonally, according to the desired shape of the article to be
produced. These projections gradually increase in size or in relief from the forward
to the rear end of the die.
In the accompanying drawings.
Figure 1 is a perspective view of a die constructed in accordance with this
invention, for forging objects which are polygonal in transverse section.
Figure 2 is a perspective view of a hexagonal bar shaped by a pair of such
Hies.
Figures 3, 4 and 5 aré diagrams representing the shape of the dies in longitudinal'

page_text: section, and showing a blank between the said dies in different positions with relation
to the surfaces thereof.
Figure 6 is a perspective view of a die for forging gear-wheels or pinions from
round bars.
Figures 7. 8 and 9 are diagrams representing the shape of the blank in longitudinal
section at different periods in, or stages of, the process of rolling, and illustrating
the manner in which the shape is gradually imparted to the forging.
Figure 10 is a perspective view of another die for forging toothed or fluted
articles.
Figures 11 and 12 are perspective views of dies for forging toothed articles the
transverse sectional area of which varies at different portions of their length.
Figure 13 is a perspective view of a pair of bevel pinions formed in one operation
by a pair of dies such as that shown in Figure 11.
Figure 14 is a perspective view of a worm-wheel or gear-wheel made by a pair of
dies such as that shown in Figure 12.
Figure 15 is a side elevation of a pair of dies for forming toothed or fluted
articles, the said dies being shown in the relative positions which they occupy when
they have just commenced to act upon the blank.
Figure 16 is a longitudinal section drawn to an enlarged scale, showing the said
dies in the relative positions which they occupy when they have about half finished
their action upon the blank.
Figure 17 is a side elevation, drawn to the same scale as Figure 15, showing the
said dies in the relative positions which they occupy when they have nearly finished
their operation upon the blank.
Figure 18 is a perspective view of one of the dies shown in Figure 15.
Figure 19 is a perspective view of a die for making forgings of similar shape in
transverse section, but with the projections and depressions extending spirally or
helically around the same, instead of being parallel with the axis thereof, as in
forgings rolled by dies such as that shown in Figure 18.
Figure 20 is a perspective view of another die for making hexagonal forgings, and
Figure 21 is a perspective view of a forging produced by a pair of dies such as that
shown in Figure 20.
a is the base or body of the die, B is the bar or blank to be rolled.
In the die shown in Figures 1, 6, 10, 11 and 12, there are spreading and reducing
surfaces which are raised from the surface of the bed a and incline upward
therefrom and which diverge from the forward or leading end of the die as at c where
the dies begin to act upon the bar or blank B substantially in the manner described
in the aforesaid former Specification No. 7028.
d is the forming or shaping surface of the die which extends between the spreading
and reducing surfaces throughout, or nearly throughout the entire length of the
die, and which is, in accordance with the present invention, shaped in longitudinal
section throughout its entire length to correspond to the transverse sectional form
which it is desired to impart to the forging.
If, for example, the object to be produced is a hexagonal bar, the forming surface d
will have a series of rounded projections or ridges as shown in Figure 1. If the
object to be produced is a toothed pinion, the forming surface d will be substantially
that of a rack which would gear with such pinion, as shown in Figures 6, 10, 11
and 12.
The co-operating dies are arranged in the machine one over the other as indicated
in Figures 3, 4 and 5 with the adjacent surfaces of their base or bed portions a
(which may be plane surfaces) separated from each other by a distance equal or about
equal to the diameter of the bar or blank to be rolled. Or the said dies may be
arranged to move vertically as described in the specification of former Letters Patent
dated 20th April A.D. 1889, No. 6759.
The relation of the reducing and spreading surfaces
the die is such that the blank is acted upon first at the
to the forming surface d of
point c and a short portion

page_text: thereof is rolled to the desired shape in transverse section, and, as the dies continue
to act upon the blank, other portions thereof are rolled to the proper shape, the
surplus metal being spread or forced axially or longitudinally outwards along the blank,
until finally the desired shape is imparted to the entire length required. That is to
say, when the dies have been operated until the blank or billet being rolled is about
opposite the point 3 on the die, the said blank will have a short portion of its length
brought to the desired shape in transverse section, and then, as the dies continue to
operate upon the blank, the proper edge is gradually imparted to the other portions
of the blank as shown for example in Figures 7, 8, and 9, the surplus metal that bas
to be displaced to bring the cylindrical blank to the desired shape being spread or
forced axially or longitudinally along the bar or blank by the surfaces b.
By modifying the shape of the forming surfaces d of the dies, various shapes may
be imparted to the bar or blank by this method of first forging a short length of
the said bar or blank to the desired shape by indenting the same or forming
depressions therein, and then gradually extending the said depressions lengthwise of
the bar or blank, at the same time spreading or forcing the surplus metal along in
the direction of the axis of rotation of the bar.
By properly proportioning the length and curvature of the waves or ridges of the
forming surface d of dies such as that shown in Figures 1, 3, 4 and 5 relatively to
the distance between the dies, the bar may be rolled to various polygonal shapes, for
example square or hexagonal the forms which are most generally used for bolt-heads
and for similar articles.
By dies of the shape shown in Figure 1, a hexagonal bar such as that shown in
Figure 2 may be produced. By dies of the shape shown in Figure 6, a toothed
wheel or pinion may be forged from a cylindrical piece of metal; and by dies of
the shape shown in Figure 10 a bar with a Auted surface may be forged. These several
shapes show that the method and apparatus are not limited to the production of any
specific shape of the forging in transverse section.
The forgings produced by the dies shown in Figures 1, 6 and 10 are uniform in
transverse section throughout their length; other shapes can, however, be produced.
For example the dies shown in Figures 11 and 12 produce toothed forgings varying
in transverse sectional area in different parts of their length. In dies for this
púrpose, the forming surface d is cut away at the middle leaving only a narrow
portion adjacent to the spreading and reducing surface on each side, so as not to
interfere with the proper rotation of the article by the portion of the reducing and
formi surfaces acting upon it at any moment. Dies such as are shown in
Figure 11 will produce a forging such as that, shown in Figure 13; whilst dies
such as are shown in Figure 12 will produce a forging such as that shown in
Figure 14.
In some instances I make composite dies for rolling articles which are circular in
transverse section and of any desired shape in longitudinal section throughout a
portion of their length and are fluted, toothed or of polygonal shape throughout
another portion of their length, as for example a bolt-blank having a polygonal
portion or head produced by dies having a portion or section like that represented in
Figure 1 and a cylindrical shank of smaller diameter produced by rolling down the
adjacent portion of the metal by dies such as are described in the said former
Specification No. 7028; the said composite die may also be made with another
portion or section for forming screw-threads on the said shank, as described in the
Specification of my Application for Letters Patent No. 10453 filed on the same day
as the present application.
In other instances I make composite dies one portion or section of which is like
the die represented in Figure 6, for forging a toothed wheel or pinion in one piece
with a reduced portion that may serve as an arbor or axle.
In the dies shown in Figures 15 to 19, the working surfaces throughout the entire
length of the die are made with ridges or projections equal in length to the forging

page_text: or the part of the blank to be rolled, so that the said dies will, at all times during the
rolling operation act upon the entire length to be rolled.
The said working surfaces are provided with a series of transverse projecting portions
or teeth d and intermediate recesses or depressions e. The height of these projections
is very small and the recesses or depressions are very shallow near the end 2 of the die
that first acts upon the blank, and the said projections gradually increase in height
or in relief and the recesses or depressions in depth to a point indicated at 4 between
the ends of the die and from the said point 4 to the end 5 of the die which acts last
upon the blank, the said projections d and also the recesses or depressions e between
them are of uniform size.
The operation of these dies, and the method of forging the article are as follows,
viz. The dies being so situated relatively to each other that the ends 2 are opposite
each other, the blank B, which may be a bar of iron, steel or other metal, is
sufficiently heated to make it plastic or yielding and is placed between the said
ends 2, as shown in Figure 15; the dies are then moved in the direction indicated
by the arrows in this Figure, thus causing the blank to rotate between them.
The smallest projections d first meet the blank and form indentations therein,
spreading or forcing the metal around the periphery of the blank, and thus tending
to increase the diameter of the blank, at those parts which enter the recesses e.
As the dies continue to move, the successive projections denter more deeply into
the blank, making lengthwise depressions therein and corresponding raised
portions that enter the recesses or depressions e of the dies; the action is thus
continued, until the parts 4 of the dies reach the blank after which the projections
and recesses or depressions of the dies of uniform size operate merely to bring all the
projections and recesses or depressions of the blank into uniformity.
The spacing of the ridges or projections along the dies is proportional to the distance
between the lies (that is to say, to the diameter of the blank) so that the ridges of
each die will come into the depressions previously made in the blank by the other
dio, and the article will thus be forged by indenting it at opposite sides, causing it to
rotate, and indenting it at different points successively around its periphery and
gradually increasing, deepening or enlarging the indentations or depressions by
successive actions at the same parts of the blank.
It is obvious that, by changing the shape of the projections on the working
surfaces of the dies, the shape of the finished forging in transverse section will be
correspondingly changed, and by making the said projections and recesses of the
dies diagonal, as shown in Figure 19 instead of at right angles to the path of move-
ment of the dies as shown in Figures 15 to 18 the ridges and depressions produced
on the blank will extend spirally or helically around the same instead of being parallel
to the axis thereof while the shape in transverse section at any point, will be the same,
the shape depending upon the shape of the dies in longitudinal section.
By making the projections scalloped or wave-shaped as shown in Figure 20 and
of proper length and curvature with relation to the diameter of the blank, or the
distance between the working surfaces of the dies, the blank will be rolled to a
polygonal shape in transverse section as shown in Figure 21.
The die shown in Figure 20 is constructed to produce a hexagonal forging, the
length of the curved ridges or projections d at the end 5 of the die being equal to
one half the distance between the dies measured at the recesses e; and it will be
"understood that, by varying the length and curvature of the projections, with relation
to the distance between them, other polygonal shapes can be produced, the principle
of operation being substantially the same as that of producing a toothed or fluted
forging by the dies above mentioned and represented in Figures 15 to 18, as the
surfaces of the polygon are practically depressions with relation to the original
cylindrical blank as indicated in dotted lines in Figure 21, and the corners or edges
of the polygon are ridges or projections with relation thereto.
The ridges on the working surface of the die represented in Figure 20 are mado

page_text: much narrower as well as shallower at the end 2 where the action begins, than at
the end 5 where the action of the die is completed, so that the depressions in the
blank are gradually widened as well as deepened, and the same is true of the dies
shown in Figures 15 to 18 although not so noticeable to the eye.
In order to ensure the proper rotation of the blank before the projection of the
dies begin to act upon it, the working surfaces of the dies near the end: 2 may be
provided with small teeth or corrugations as represented in Figures 18, 19 and 20
which will engage with and positively rotate the blank without producing marks that
will be too deep to be obliterated by the subsequent action of the dies; and if
required the working surfaces of the dies may also be provided with teeth along the
sides of the shaping portion as represented at a¹ which will engage with the blank
beyond the ends of the portion that is being shaped by the dies.
This construction should be adopted when the depression and elevation of the
working surfaces of the dies are not themselves sufficiently prominent to ensure the
uniform rotation of the blank.
These improvements may also be applied to portions or sections of composite
dies whereby portions of the forgings may be made circular in transverse section
and other portions polygonal, fluted or of other desired non-circular shape in transverse
section.
The different parts of the said composite dies may act consecutively, or they
may act simultaneously whenever the rotation of the blank can be uniform at
the different points that are acted upon at the same moment by different parts of
the die.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I wish it understood that I claim :-
First. The improved method of manufacturing a toothed, fluted, polygonal or
similar forging, consisting in first imparting the required shape in transverse section
to a portion of the bar or blank by forming indentations or depressions at suitable
intervals around the same, and then gradually extending the said indentations or
depressions lengthwise of the blank, at the same time spreading or forcing the
displaced metal longitudinally outwards, until the required shape in transverse
section is imparted to the entire length of the forging, substantially as described.
Second. The herein described method of making rolled forgings, consisting in
forming indentations or depressions at suitable intervals around the bar or blank
while rotating the same about its axis, and then gradually enlarging such indentations
or depressions by repeated pressure therein and by spreading or forcing the displaced
metal around the blank to form thereon projections or ridges between the said
indentations or depressions.
Third. A die for use in the manufacture of toothed, fluted, polygonal or similar
forgings as above set forth, which has its raised working portions of the same height
from end to end of the die and which is provided with inclined diverging spreading
and reducing surfaces substantially as described with reference to Figures 1, 6, or 10
of the drawings, for the purposes specified.
Fourth. A die for the purpose above specified, having a working portion which
comprises alternate transverse ridges and depressions, and the middle or central
part of which near the rear or finishing end of the die is absent or is cut away,
substantially as described with reference to Figure 11 or to Figure 12 of the drawings,
for the purpose specified.
Fifth. A die for the purpose above specified, the working portion whereof comprises
alternate transverse ridges and depressions the height and depth of which increase
from one end of the die nearly to the other end thereof, the ridges and depressions
which finally engage with the forging being of uniform dimensions, substantially as
described with reference to Figures 15 to 18, or with reference to Figure 19 or to
Figure 20 of the drawings, for the purpose specified.

page_text: Sixth. Astoothad forging manufactured as hereinbefore described and the transverse
sectional area of which aries at different.parts throughout its length.
1. Seventh. A composite (die one of the portions or sections of which is provided
with alternate ridges and depressions extending at an angle to the direction of imove-
*ment of the die, with or without surfaces for spreading or forcing the surplus-metal
slongitudinally outwards, for the purposes ahove specified.
HASELTINE, LAKE & ¹Co.,
143
.19
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