Process and Apparatus for Rolling and Shaping Tubes and other Hollow Bodies.
Year: 1892

page_text: Date of Application, 13th Apr., 1892-Accepted, 14th May, 1892
COMPLETE SPECIFICATION.
Process and Apparatus for Rolling and Shaping Tubes and other
Hollow Bodies.
I, REINHARD MANNESMANN Junior of Remscheid-Bliedinghausen in the
Empire of Germany Engineer, 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 and apparatus for rolling metals which are
modifications of the methods and apparatus described in the Specification to my
application for Patent dated 8th March 1892 No. 4595 wherein rolls were mounted
on axes on revolving bodies, round whose axes the rolls consequently had a planet-
like motion, such rolls having eccentric or tapering grooves which, at each
revolution of the rolls round the axes of the said body, were made to act with one
and the same part of the groove upon the metal object or work piece to be operated
upon. According to the present invention, the said rolls, instead of having
eccentric grooves, are formed with concentric grooves, that is to say, grooves of
uniform cross section, so that instead of definite parts of the grooves being always
brought in contact with definite parts of the work piece, the rolls can in the present
case, revolve freely upon their axes, so that they do not always come in contact
with the work piece at a definite part of their groove.
This construction of rolls is mainly applicable for effecting very small alterations
of the section of the work piece, as this is acted upon both on its worked and on its
unworked portion by one and the same form of groove. The rotation of the rolls
on their axes by means of toothed wheels and toothed rings, as described in the
former Specification, can in this case be dispensed with, so that the entire rolling
mill mainly consists of two or more oppositely revolving roll-like bodies which at
their periphery carry one, two, or more loosely revolving rolls, that act upon a
hollow or tubular work-piece mounted on a mandrel between the two revolving
bodies. In consequence of the dispensing with the toothed wheels, the speed with
which the rolls act upon the body can be greatly increased.
The work-piece is passed between the revolving bodies either with an inter-
mittent motion or with a continuous motion, it being generally at the same time
made to receive an intermittent or continuous rotary motion or partial or recipro-
cating motion round its own axis, so as to be acted upon at all points of the
periphery. The work-piece is acted upon from the one end towards the other so
as to be brought along its entire length to the required thickness, and its conversion
from a thicker to a thinner condition can be effected in a single passage through
the rolls.
The accompanying drawings shew arrangements of rolls for carrying the inven-
tion into operation.
Figs. 1 2 and 3 shew vertical sections of rolling mills-operating in the before
described manner-with continuous forward and at the same time intermittent
rotary motion of the work piece. While it is being acted upon by the rolls, it
only receives a longitudinal motion, while the partial rotation thereof by preference
through 90° is effected in the time between the cessation of the action of the one
roll, and the commencement of the action of the next one. The rolls are preferably
made with a groove on their entire periphery having a half round or oval section,
if it be intended to produce cylindrical tubes. Other sections, such as square,
hexagonal, star-shaped and other regular sections can be produced if care be taken
to effect the exact partial rotation of the work-piece through a corresponding angle
during the intervals between the action of the rolls.

page_text: If each rotation body carries two working rolls as at Fig. 1 rectangular and
other profiles can be rolled, if the grooves of the two rolls are made corre-
spondingly different from each other so that the one roll acts upon the "high" side
of the section and the second one on the "flat" side.
Circular and square profiles can be rolled with any number of rolls, while
rectangular and oval sections require an even number of rolls. Also, irregularly
shaped profiles can be rolled with a corresponding shape and number of the rolls.
For carrying out the method of rolling represented by the arrangement of rolls
shewn at Figs. 1, 2 and 3, two driving bodies a rotated in the direction of the
arrows by toothed wheels are provided with 1, 2, 3 or more working rolls b which
are supported by axes c in the bodies a. As soon as tube k of plastic material such
as red-hot steel is brought by means of a mandrel m between the working rolls, the
mandrel being prevented from shifting longitudinally while the bodies a revolve in
the direction of the arrows, the tube will be rolled out to a certain length. During
this rolling, the rolls are held by frictional contact with the work piece, and
consequently roll upon the same, while at the same time the axes c turn in the
body a.
After the working rolls 6 have left the work-piece, the latter is preferably
turned through an angle of 90°. The next pair of working rolls is then brought
by the rotation of the bodies a in contact with the work piece and again acts upon
a certain length thereof, pressing the same forward so as to elongate it.
The mandrel may either be allowed to pass with the tube between the rolls,
either at the same or at a different speed, or it may be prevented from advancing,
while the tube upon the same is forced or drawn forward either by hand or by a
mechanical device.
Fig. 4 shews a plan of one of the bodies a operating as above described, in which
the rolls b are arranged with their axes in an oblique position so that in rotating,
at the same time that they act upon the tube in a longitudinal direction, they also
impart to it a rotary motion, thus rendering the special rotation of the work piece
unnecessary.
The motion of the driving bodies a can be effected in the direction of the
arrows n when the working rolls a revolve in the direction of the arrows n¹. The
working rolls in this case act upon the work piece first at the unworked part
thereof, and roll towards the part which has already been worked; if, on the other
hand, the motion of the said parts be reversed, the working rolls first come in
contact with the part already worked, and roll towards the unworked part.
In place of one of the driving bodies, for instance the lower one, may be
substituted a support or anvil having a suitably formed groove for supporting the
work piece while being acted upon by the upper rolls.
In the arrangement at Fig. 1 two working rolls are made to act simultaneously
on opposite sides of the work piece so as to serve reciprocally as supports to each
other.
Instead of arranging the working rolls to rotate free on their axes, so that they
are made to turn by the frictional contact with the work piece, they can be
continuously rotated by fixing thereon toothed rings which are made to gear with
a large fixed toothed ring, in the same way as the working rolls described in my
before mentioned previous application, but such an arrangement would in most
cases be unnecessary.
The number of the driving bodies, and of the working rolls mounted thereon is
optional. Figs. 5 and 6 are sections at right angles shewing by way of example
the arrangement of four driving bodies each with two working rolls, by means
of which the work piece is simultaneously acted upon on four sides at the same
part.
Instead of causing the working rolls to act simultaneously on four sides, two, for
example, the top and bottom one may be made to act on the work piece alter-
nately with the two side ones. If each roll has a half-round or oval groove, the
lateral fins produced in rolling are always rolled off by the next pair of rolls and in

page_text: this case no rotation of the work piece is required for insuring the action upon the
work piece on all sides.
If during the rolling process the distance of the driving bodies from each other
be increased or decreased, the external diameter of the produced tube is rendered
tapering. If during the rolling process a conical mandrel be employed and this be
shifted longitudinally relatively to the central axis of the rolling mill the tube will
have a tapering bore imparted to it. If both the above operations be effected
simultaneously, the tube will receive both an internal and an external tapering
diameter. If the change of position of the driving bodies and mandrel be effected
at intervals, the tube will receive a stepped configuration, either internally or
externally or both.
As described in my said previous application, the axes of the rolls may either be
placed parallel to the axis of the driving body, in which case they would describe
cylinders round the same, or they may be inclined thereto, in which case they will
describe cones, or they may be placed obliquely as at Fig. 4, in which case they
will describe paraboloids.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. The method of rolling, finishing or forming tubes and other hollow bodies
upon a mandrel by means of rolls mounted upon rotating bodies, round whose axes
the axes of the rolls describe cylinders, cones or paraboloids, such rolls having
grooves of uniform section round their periphery, and being made to perform
complete or partial revolutions round their own axes in rolling repeatedly upon a
portion of the length of a tubular work piece which is made to advance
continuously or intermittently, and is thereby acted upon in successive portions
along its entire length, substantially as described.
2. For carrying out the method of operating referred to in the preceding claim,
a rolling mill consisting of one or more revolving driving bodies, in which are
mounted one or more rolls having circular grooves of uniform section throughout,
and which, in revolving round the axis of the driving body, also receive rotary
motion round their own axis, in combination with a mandrel or other tool carrying
the hollow body to be operated upon, substantially as described.
3. In the method of operating referred to in the first claim, the arrangement of
the rolls whereby either the work piece is acted upon thereby from the thick
towards the thin end, or the work piece is acted upon thereby from the thin end
towards the thick end, the rotation of the work piece round its longitudinal axis
being effected either during the time it is acted upon or in the intervals during
which the rolls do not act thereon, substantially as described.
4. In the method of operating referred to in the first claim, effecting the
separation of the work-piece or parts thereof from the mandrel by imparting to
the latter during the rolling process, or during the intervals between the same, a
motion different from that of the work piece, or of parts of the same, substantially
as described.
5. In the method of operating referred to in the first claim, the production of
hollow bodies whose section is made to vary in the direction of their length,
either:
a. By varying the distance apart of the driving bodies during the rolling
process, for varying the external configuration, or :
b. By varying the position of the mandrel relatively to the axis of the rolling
mill during the rolling operation, for varying the inner configuration, or:
c. By varying both the distance apart of the driving bodies and the position of
the mandrel relatively to the axis of the rolling mill, for varying both the
internal and the external configuration of the hollow object, substantially as
described.
6. In the construction of rolling mill referred to in the second claim, the use of

page_text: two, three, four or more driving bodies with their working rolls which act upon
the work piece periodically at different peripheral points of one and the same part,
either simultaneously or consecutively, or in pairs substantially as described.
7. In the construction of rolling mill referred to in the second claim, the use of
an anvil and mandrel as support for the work piece while this is acted upon by the
working rolls, substantially as described.
8. In the construction of rolling mill referred to in the second claim, effecting
the rotation of the working rolls upon their axes by the frictional contact with the
work piece, substantially as described.
Dated this 13th day of Anril 1899
ABEL & IMRAY,
Agents for the Applicant.