An Improved Method of and Apparatus for Rolling Wire.
Year: 1891

page_text: Date of Application, 17th Feb., 1891-Accepted, 4th Apr., 1891
COMPLETE SPECIFICATION.
An Improved Method of and Apparatus for Rolling Wire.
I, HENRY ALEXIS, WILLIAMS, of Taunton, Massachusetts, United States of
America, Manufacturer, 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 relates to a method of reducing and shaping metal rods to form
wire, by rolling, it being possible by this method to produce wire by rolling the
metal when cold and the invention also relates to the construction of the rolls
employed.
Attempts have been made to produce wire by cold rolling such attempts have
been unsuccessful, and the cold rolling of wire has not come into commercial use.
In the process of cold rolling as heretofore suggested and attempted, the metal
acted upon becomes hardened and brittle, in the successive reductions, so that it
finally splits or cracks longitudinally and thus fails to produce a commercially
valuable product.
This invention is based on the discovery that by applying the compressing force
to the metal in a certain definite way, the latter is reduced in sectional area and
elongated without any tendency to harden or become brittle, or to split but on the
contrary with an actual annealing effect, so that rods which are originally quite
hard, and have but little malleability come out after the successive reductions
annealed and with their tensile strength increased, and by this process it is possible
to produce wire of any desired sectional shape and gauge without drawing and
annealing as has heretofore been necessary in order to produce a similar effect.
The effect of the rolls on the metal in any rod rolling or wire rolling process is
first to diminish the sectional area of the metal at the point acted upon by the rolls,
and second to elongate the metal, as the portion that is displaced in reducing the
diameter or sectional area increases the length of the rod.
In the rolling processes as heretofore generally practised, the sectional shape of
the rod is varied at each successive action, one pair of rolls for example increasing
one diameter without varying the other, and the next pair of rolls decreasing the
diameter transverse or at right angles to that on which the compression previously
took place.
For example if the rod were originally square, the first reduction would act mainly
at two diagonally opposite corners reducing the metal to a lozenge shape, with the
obtuse angles at the corners which have been acted upon by the rolls.
The next pair of rolls would compress mainly on the line connecting the acute
angles of the lozenge produced by the preceding pair, and would reduce the same
to a similar lozenge of smaller size, the obtuse angles of the new smaller lozenge
taking the place of the acute angles of the preceding larger lozenge.
In other words, when rolls having a V-shaped groove are used they commonly
compress or displace the metal more at the apex of the V or bottom of the groove
than near the sides of the groove where the two rolls of a pair come together.
For example, the grooves in each pair of rolls are obtuse angled, and as the
plane of each pair of rolls is at right angles to that of the preceding pair, or if the
planes are all parallel the rods are caused to make a quarter turn in passing from
one pair to the next, each roll of the pair acts upon an acute angle of the rod and
compresses it down to an obtuse angle, thus making the intermediate angles acute
which in turn are compressed to obtuse angles by the next pair of rolls, or if the
shapes are rounding instead of rectangular the grooves of the rolls are elliptical
instead of circular in shape each-pair acting to compress the rod presented to it on.

page_text: the line of the major axis of the ellipse, forming the cross section of the wire, and
reducing it so that it becomes the minor axis of the elliptical shape imparted to the
rod in passing through the rolls.
In this plan the compression towards the axis of the blank is unequal, being
greatest across the middle diameter on the line of compression and being substantially
nothing at the ends of the transverse or shorter diameter.
This action produces a greater flow of the metal in some parts than in others, the
metal displaced at two opposite corners of the lozenge being far greater than at
the intermediate corners, so that the tendency to elongate is greater at the first
mentioned corners than at the others.
In other words, in elongating the rod for example ten per cent., or extending a
piece originally ten inches long to a piece eleven inches long, the tendency to stretch
or elongate in certain portions is far greater than in others so that the elongation of
these parts would naturally be in the neighbourhood of twenty per cent. or two inches
in ten while other parts are only slightly reduced laterally and consequently have
but little tendency to elongate but by their connection through the body of the
metal with the parts that tend to have greater elongation, they tend to resist that
greater elongation, and consequently severe internal strains are brought to bear
upon the rod which in the repeated operations finally disrupt it, and even if the
metal is not finally broken up or split longitudinally the strains are such as to make
it brittle and of a very inferior quality for wire.
By the present method this internal strain on the metal tending to disrupt the
same, can be wholly obviated and the compressing action caused to act with
uniform tendency to elongate the metal on all parts of the sectional area of the
rod thus causing the metal to flow uniformally, casily, and naturally in the direction
parallel with the axis, the tendency being rather to increase the tenacity or integrity
of the fibre of the metal than to disrupt the same.
This result is effected in accordance with the present invention by applying the
pressure and reducing the metal substantially uniformally over the entire surface of
the part acted upon by a pair of rolls.
In other words all parts of the surface acted upon by the rolls approach the
diameter of the blank at right angles to the plane of the rolls substantially equally,
instead of having the middle portion of the said surface approach the diameter far
more than the end portions as has always been practised heretofore in rolling metal.
In operating upon metal in accordance with this invention a continuous train of
rolls is employed the rod passing from one pair of rolls directly to the next pair so
that the heat which is generated by the flow of the metal itself is to a certain
extent preserved and the flow of the metal at the several successive sections is
nearly continuous, and better results are attained than if the metal had the time to
cool and come to rest as it were, between the successive reductions.
As the space enclosed between the peripheries of each succeeding pairs of rolls is
smaller than that between the preceding pairs, there must be a slight departure
from the exact parallelism between all parts of the sectional shape of the groove,
and that of the metal presented to it, which departure is in the form of a slight
truncation or filling up of a portion of the bottom of the groove such that the
distance between the truncated portions or bottoms of the grooves of a larger pair
of rolls is equal to the width of the top of the grooves in the next smaller pair.
Figure 1 is a diagram representing the successive pairs of rolls employed for
rolling wire in accordance with the method of forming the subject of this invention.
Figure 2 an elevation on a plane parallel to the axes of two consecutive pairs of
rolls of a train of rolls, embodying this invention, on a larger scale.
Figure 3 is a diagram showing the outline of the grooves of the several successive
pairs of rolls, of a train embodying this invention, being partial sections in the
planes of the axes of the pair of rolls.
Figure 4 a diagram showing the sectional outlines of the rod or wire at the
successive passes, each figure showing the shape of the wire as it approaches a given

page_text: pair of rolls, and also the shape imparted to it after passing through the said pair of
rolls, the shaded lines between the two outlines showing the direction of the com-
pression and the portion of the metal displaced.
Figure 5 a similar diagram showing the shape imparted by rolls having grooves
of different shape from those used to produce the shapes shown in Figure 5, but
having substantially the same results and producing substantially the same
conditions as to flow of metal and compression and clongation of the rod.
Figures 6 and 7 illustrate diagrams the former showing the mode of reducing the
metal in accordance with this invention, and the latter showing the mode heretofore
commonly adopted.
Figure 8 a modification in the shape of the rolls, and
Figure 9 a diagram showing the shape of the blank produced thereby.
The reduction of the metal is effected by a train of rolls a a² a³ a which may be
operated in any suitable machine being driven at the proper speed to act on the
metal which passes between them, reducing the same in diameter, and elongating it
while it is carried forward by the rotation of the rolls.
In the diagram illustrated in Figure 4, the method is shown as applied to the
reduction of a square rod which is finally reduced to a round wire d.
For convenience in description, the diagonals or diameters of the rod will be
marked, the one marked in each case being on the line of the pressure of the
rolls, by which the blank is about to be acted upon and the one marked y at right
angles to the line of said pressure or parallel with the axis of the rolls acting on the
metal at that point, being the line of pressure of the rolls that have just previously
acted upon the blank to bring it to the shape shown.
The first pair of rolls acts upon the blank on the line of the diameter the
compression being applied practically evenly over the sides 2, 3, in the direction
parallel to the line a and the bottom of the groove in the roll being truncated so as
to produce additional compression just at the corner 2, flattening it down and thus
bringing the blank to the shape shown at 20.
The second pair of rolls acts on the blank 20 compressing the same on the line a
and acting uniformally over the entire sides 2, 3, so that the points 2 approach the
line in the compression practically the same amount as the points 3 except for the
fact that the rolls are also slightly truncated, so that the corner 3 is flattened again
as before described bringing the blank to the shape shown at 30.
The same operation is repeated on the blank 30 reducing the same to the shape
shown at 40 which is again acted upon and brought to the shape shown at 50 which
is nearly the minimum reduction required, so that the final action is merely to bring
the blank to the required sectional shape shown at d without further reduction than
is necessary to change from the shape shown at 50 to that shown at d.
Except for the slight truncating action at the point or apex of the part acted
upon by the rolls, the rolls compress the blank evenly and uniformally over their
entire width.
In other words the line 2, 3, of the blank at 20 is moved with a parallel movement.
to the position shown at 3, 2 in blank 30, and so on, and in such compression as this
the flow of the metal is entirely lengthwise and substantially equal in all parts of
the blank, so that the rod is clongated at each pass without tendency to split it.
Except for the slight truncated portions 2, 2, it will be seen that the sectional
shape of the rod is exactly the same at each successive pass while in the process of
rolling as heretofore practised, the sectional shape changes at each pass.
In other words, in the former process the compression instead of being uniformally
applied at all parts of the sides corresponding to those marked 2, 3, is greatest at
the point 3 and nothing at the point 2, and the side 2, 3, acted upon by the roll
instead of being moved parallel with itself towards the diameter y moves with what
may be called a pivotal movement around the point 2, the end 3 being carried in
towards the diameter y, while the end 2 is not carried in at all.
This difference in operation is readily understood from Figures 6 and 7 in which

page_text: the shaded portions show the amount of metal displaced in making one pass and the
difference in effect on the metal will be readily recognized.
In the plan illustrated in Figure 6, an equal amount all over the blank except for
the slight amount enclosed in the triangles at is displaced and flows longitudinally
causing a corresponding elongation of the rod, while in the plan shown in Figure 7,
a very large amount of metal is displaced at the point and almost none at the
point y.
There is thus great tendency to elongate the blank at the ends of the diameter .,
while there is almost no elongation at all at the ends of the diameter y, except what
is produced by the dragging action of the particles at, exerted through the body
of the metal upon those at y.
In other words, instead of elongating all parts of the rod equally, and consequently
without internal strain as is the case in the method forming the subject of this
invention the elongation was in the former plan confined to certain portions in the
metal which elongation was resisted by the tensile strength of the parts not displaced
by lateral pressure, thus producing internal strains by which the rod was made
brittle or even entirely torn apart and split.
The difference in effect between the two plans of operation can be easily under-
stood by dividing the sectional area into four parts on the lines ² ² y² y².
In the plan shown in Figure 6, it will be seen that the amount laterally displaced
to go into the increased length is substantially the same in each of the four sections
all of which will be elongated substantially equally, while in the plan represented in
Figure 7, a very large percentage of the quarters a², y² will be displaced laterally
and tend to elongate the said quarters, while only an extremely small portion of the
quarters yy will be displaced laterally.
Thus the first mentioned quarters will tend to elongate far more than the last
mentioned which latter will hold back or resist such tension bringing an internal
strain which tends to shear or split the metal longitudinally and, after a number of
successive passes of this kind, will do so or at any rate will bring the metal into
such condition that it is unfit for use as wire.
?"
If the rods were made of a bundle of four separate rods instead of a single
integral one as shown, the elongation of all four would be nearly equal with the
reduction shown in Figure 6, those opposite the letter having only a very small
percentage greater elongation (owing to the truncating of said corners) than those
opposite to the letter, while with the plan represented in Figure 7 the two
opposite the letters would have several times as great reduction and consequent
elongation, as those opposite the letters y and it is this unequal elongation in
different parts of the rod, or rather the tendency to elongate unequally resisted by
the internal strains in the rod itself that has been undoubtedly the reason for the
failure to produce wire by cold rolling in the plans heretofore tried. The same
action of course takes place when the metal is treated hot, as in the operation of
reducing billets to rods preparatory for making wire, but as the hot metal flows
more readily, the internal strains are not so great and their effects are not so
objectionable although there would undoubtedly be an advantage arising from
applying the reduction in accordance with the herein described method even in
hot rolling.
The invention is not necessarily limited to the square sectional shape of the rod
herein shown for the purpose of illustration, as the same plan might be applied with
other shapes, the essential feature being that the lateral compression or displacement
is substantially uniform on all parts of the surface so that all parts are subject to
equal tendency to elongate or substantially so.
In operating upon circular shapes in accordance with the improved plan the
circular shape would be retained at each pass except for a slight flattening at the
ends of the diameter in line with the compression applied, as illustrated in Figure 5,
while with the old plan of rolling substantially circular shapes the rod is brought to
elliptical shape at each pass, that, which was the larger diameter of the ellipse

page_text: before a given action of the rolls, becoming the shorter diameter of the ellipse after
the wire has passed through the rolls, so that the portions near the ends of the
longer diameter tend to elongate far more than the portions near the ends of the
shorter diameter producing the objectionable internal strains above mentioned.
When circular shapes are treated the truncation of the bottoms of the grooves
causes a larger percentage of difference in the amount of depression in the different
parts of the rod than when square shapes are used, as will be seen from Figure 5,
and for such shapes the form of rolls illustrated in Figure 8 may be found more
desirable.
In this construction instead of flattening or truncating the bottom of a groove of
a preceding pair of rolls so as to reduce the width of the rod acted upon, at this
point to the width of the groove in the next pair of rolls, the following plan is
adopted that is, the edges of the grooves of the following pair of rolls are cut away
as shown at e so that the extreme width of the grooves of a following pair is equal
to the diameter of the groove of the preceding rolls thus giving a reduction in the
form shown in Figure 9. This leaves a slight projection on the blank as shown at e²,
coming at the edges of the grooves in the rolls by which the blank has been brought
to this shape but such ridge coming at the bottom of the groove of the next pair of
rolls so that it is readily compressed into the mass of the rod.
It is only necessary that such widening of the grooves at e shall be of such shape
as not to form too thin a projection in the nature of a fin, since if a thin fin were
formed it would probably break off or fail to compress properly into the mass of
metal but by forming a substantially V-shaped ridge as shown in Figures 8 and 9,
said ridge is readily compressed into the mass of metal by the following pair of rolls,
and it will be seen that the reduction is very nearly uniform all over the blank.
The principle of constructing the grooves in the rolls represented in Figures 2 and 3
will be readily understood from the preceding description.
The grooves in the successive pairs of rolls, are of the same shape, the compressing
face of a preceding pair of rolls as a being parallel to the face of the following
pair, while the width of the groove measured on the line y is less in the following
pair than in the preceding pair by the amount of compression that is to take place,
and in order that the following pair may take in or act upon the whole of the blank,
coming from the preceding pair, the bottom of the groove of the preceding pair is
filled up to just such an extent that the distance between the filled up bottom of the
groove of the preceding pair is equal to the width on the line of the groove of the
next following pair.
It is obvious that instead of filling the bottoms of the grooves they might be made
of full rectangular shape and the corners of the blank rolled in by an extra pair of
rolls sufficiently to bring the blank down to the width of the next following pair of
grooved rolls, such intermediate pair producing no compression or elongation of the
rod except such slight flattening of the corner as is produced by the truncated or
filled up portion of the grooves of the rolls as shown.
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 I
claim is :-
:-
First. That improvement in the art or method of rolling wire which consists in
subjecting all the parts of the surface acted upon at a given pass to substantially
uniform pressure and displacing substantially equal amounts of metal at all points
acted upon by the rolls, substantially as and for the purpose described.
Second. A train of rolls the grooves of which have their surfaces substantially
parallel throughout the train the bottoms of the grooves in each pair terminating in
a flattened or truncated portion whereby the width of the space included between
the pair of rolls is less measured between the bottoms of the grooves than the width
at the tops of the grooves, the width between the bottoms of the grooves of a given
pair being equal to the width at the top of the grooves in the next following pair,.
substantially as and for the purpose described.

page_text: Third. A train of rolls the acting faces of the grooves of which at their meeting
points are substantially parallel with the faces of the rods to be acted upon by them,
substantially as and for the purpose described.
Fourth. A train of rolls the aeting faces of the grooves of which at their meeting
points are substantially parallel with the faces of the rod to be acted upon by them,
the width of the groove at the meeting point of the rolls being equal to the width or
diameter of the rod presented to them, measured in the same direction, substantially
as described.
D
1
1001
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.