IMPROVEMENTS IN ROLLING MILL TRAINS FOR COMPRESSING METALLIC SHAPED PIECES
Year: 1884

page_text: I, JOSEPH LARDON, of Firminy (Loire), Republic of France, Engineer, do hereby
declare the nature of said invention for "IMPROVEMENTS IN ROLLING MILL TRAINS
FOR COMPRESSING METALLIC SHAPED PIECES" 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 improvements in rolling mill trains and has for
object to provide apparatus designed to effect, by the process of rolling the
compression and consolidation of heated pieces or objects of metal, either solid
or hollow, having the form of solids of revolution. The pieces or objects are
subjected to this rolling action after they have received their final shape, a littlo
extra thickness of metal being allowed, in order that they may have the required
size, after they have been consolidated.
The improved rolling mill trains consist of three or more rollers, of cylindrical
or conical form, generally smooth.
When the generatrix of revolution of the piece which has to be compressed is
not straight the rollers are provided with conical rings.
In the accompanying sheet of drawings A. Fig 1 is a block of crude cast or
forged metal just taken from the re-heating furnace and designed, for instance, for
the manufacture of shells.
By placing the said block between the rollers B which are equi-distant, and
causing the said rollers to rotate, this block or piece will revolve between the
rollers in a reverse direction to that of the latter. If one of the rollors is then
brought slightly nearer to the other two than it was at first, each of the three will
compress or indent the metal to a certain extent, and at the completion of a third
of a revolution such compression or indentation will have been extended over the
whole surface of revolution. The object under treatment will be consequently
reduced in diameter. If the feeding or approach of the roller be steadily continued
the metal will acquire an homogenity and a density which will increase its
hardness, its toughness and its elasticity and at the same time it will be reduced
to its required size. This block or piece of metal may be converted by means of

page_text: a block hammer into two ogivo-cylindrical projectiles a, b Fig 2 that is when it is
not designed to form a single cylindrical projectile. The piece or object to be
submitted to this compressing or consolidating process may be of many different.
forms. For instance it may, like the block A be a solid cylinder or it may be
hollow, and cylindrical both internally and outwardly like the sleeve C, Fig 3, or
it may be cylindrical inside only, like the sleeve C Fig 4, or conical inside like the
sleeve C Fig 5, or finally it may be conical inwardly or outwardly like the
sleeve C Fig 6. The said piece may also be partly cylindrical and partly conical
outwardly while leing cylindrical inside, like the gun-barrel D Figs 7, 8 and 9.
Such a piece may be rolled in two successive operations the first operation being
performed by a train composed of smooth conical rollers Fig 7, and the second by a
train composed of smooth cylindrical rollers Fig 8 or it may be rolled at one
operation by the train shewn in Fig 9. In this train the rolls are provided at the
right hand end with moderately thick rings c. c. c noveable upon their axes so that
the surfaces in contact should move with speeds as nearly as possible equal to one
another.
In order that the compression or consolidation may be carried out with regularity
and efficiency and that the length of the object or piece under treatment may not
vary, the rollers, when of cylindrical shape, aro provided at their extremities with
projecting collars between which the piece under compression is held, the said piece
being thus rolled as if it were enclosed in a matrix and is consequently incapable
of extension.
When the cylinders are conical, the projecting collars F (Fig 9) mercly serve to
keep the movable rings in position, the necessary support to the metal being
afforded by the conicity of the rollers.
When hollow objects or pieces are treated they are generally provided with a
mandrel N or N¹, which supports them against collapse under the compressive
strain of the rollers and exerts by means of a collar G when the mandril is
cylindrical Figs 7, 8 and 10, or by reason of its conical form, when conical,
Figs 5 and 6, a pressure which may be rendered powerful enough, by means of
hydraulic or other device, to slightly enlarge the hollow portion and give it the
necessary calibre.
When this method of compression or consolidation is applied to the manufacture
of sleeves or barrels formed by twisting or coiling wires or bars of the same
metal, or of iron or steel alternately, in order to produce Damascus guns (Fig 10),
another ring 1 is combined with the ring G and rests against the projecting collars
of the rollers.
When the metal piece has the form of a solid of revolution with curved parts, as
in the case of the ogivo-cylindrical shell J shewn in Fig 11, the left hand portion
of the rollers is solid and the curved part is formed of the movable rings c. c. c
while the projecting collars F. G (the latter shrunk on the roller) continue
to support the extreine ends of the metal pieco in order to prevent it from
elongating.
When the metal piece under treatment has the shape of a solid of revolution,
such as K (Fig 12) and is cylindrical internally while its contour exhibits slight
projections and depressions 'the main portion of the rollers is made a fixture while
the other portions c. c. c are movable. But it is preferred in such a case, to make
the piece or object of cylindrical shape after compressing a portion of it, to shapo
it finally in the lathe.
With regard to the manufacture of gun or other barrels (such as L, Fig 13)
which have been made to assume a conical form by well known apparatus, the piece
of iron cut to length is inserted between the conical rollers, its extreme ends being
in contact with the inside edges of the solid projecting collars. E F fig 14 of onu
roller which is gradually moved towards the other two.
This roller may without sensible inconvenience be moved towards the other two
by a circular motion around a distant point near the junction of the axes of the

page_text: cones, especially if its axis at the beginning of the operation be directed beyond
the common point of junction so as to fall slightly within such point at the end of
the operation.
The axis of the roller is pivotted on a transverse axis n (fig 14) situated at the
said junction point.
The rolling operations above referred to must not be understood in the ordinary
sense of the term but in the sense of compressing, squeezing condensing or
hardening the metal without sprending it or increasing its length and without
shaping it; the above described rolling mill trains are not intended for shaping
metallic pieces, a process which gives rise to variations of speed the effect of whichi
is to twist and crack the metal Pieces or objects of metal should only be subjected
to the treatment of the above described roll when they have been cast, forged by
hammers or rolled in the usual way into their final size with the addition of a
certain amount of extra thickness of metal allowed for the reduction in size causod
by compression.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim in a rolling mill train designed for the compression or consolidation of
heated metallic pieces or objects either solid or hollow, which have previously been
reduced to the final form, save only for a slight excess in their diameter, is —
1. The use of three or more cylindrical or conical equidistant smooth rollers such
as B. B. B. figs 3, 4, 5 and 6 provided with projecting collars E. F., one of the said
rollers being capable of lateral displacement, the whole substantialy as described
and illustrated and for the purposes specified.
2. The use for the compression by successive rollings of a piece or object having
the form of a common tube, with a conical part or chase, and a cylindrical part or
breech of equidistant and conical smooth rollers, such as B. B B. fig. 8, and B¹ B¹ B¹
Fig 7, in combination with a mandrel such as N¹ and collar G substantially as
described.
3. The uso for the compression by rolling at one operation of the cylindrical and
conical parts of a piece or object having the form of a cannon tube, of three or
more cylindro-conical, equidistant smooth rollers such as those shewn in Fig 9,
provided with movable rings c. c. c forming the conical part projecting collars E
and a guard ring F, in combination with the mandrel N substantially as described
and illustrated.
4. The uso for the compression of sleeves, tubes and the like formed by twisting
or coiling wires or bars of iron or steel or of iron and steel alternately of cylindrical
equidistant smooth rollers such as B. B. B Fig 10 with projecting collars F. in
combination with the collar G the mandrel N and the ring I substantially as
described.
5. The use for the compression by rolling of ogivo-cylindrical solid projectiles of
three or more cylindrical and curved, equidistant smooth rollers such as thoso
shown in Fig 11 with projecting collars and with movable rings c. c. c substantially
as described and illustrated.
6. The use for the compression by rolling of solid or hollow shaped pieces of
simple but irregular form of three or more cylindrical equidistant smooth rollers
such as those shewn in Fig 12 with projecting collars E. F and movable rings c. c
in combination with the mandrel or cylinder N₁ substantially as described.
7. The use for compressing by rolling of solid or hollow shaped pieces of simple
form such as the conical bars used in gunmaking of three or more conical, smooth
and equidistant rollers, such as those shown in Figs 13 and 14, one of the said
rollers being provided with projecting collars engaging with corresponding circular
grooves in the other rollers substantially as described.
8 In a rolling mill train for compressing metal of simple solid or hollow forms,
the combination of three (or more) smooth equidistant and cylindrical rollers or

page_text: conical rollers (such as B. B. B. or B¹ B' B') provided with projecting collars E. F.
and movable rings c. c. c mounted opposite the curved or conical parts, more or
less indented, of a piece of metal, (under treatment) having also a cylindrical part;
the external compression thus applied being combined with the thrust exerted by
the inside conical or cylindrical mandrel N or N' respectively or by the collar G in 5
combination with the ring I substantially as described and illustrated.
Dated this 8th day of November 1884.