Rolling Mills for Making Tubes from Hollow Metal Ingots.
Year: 1888

page_text: Rolling Mills for Making Tubes from Hollow Metal Ingots.
I, STEPHEN PASCHALL MORRIS TASKER, a citizen of the United States residing in
the City of Philadelphia, County of Philadelphia, State of Pennsylvania, 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 :-
The object of my invention, broadly stated, is the manufacture of a tube from a
hollow cylindriform metal ingot (preferably a steel cast ingot) by the simultaneous
subjection of the external surfaces of said ingot (either hot or cold) to the action of
external compression rolls, and of the internal surfaces of said ingot to the action of
positively driven rolls which subserve also the office of a ball or mandrel proper,-
the result of the said subjection being not only the positive feeding of the ingot
through the rolling mill constituted by the rolls referred to, but the compacting,
consolidation, thinning and reduction of the substance of the walls of the ingot and its
consequent extension or increase in length.
Broadly stated, my invention comprehends the employment, in an organized
machine for producing tubes from hollow cylindriform ingots, of a roller mandrel the
rolls of which are positively driven, in combination with a set of external compressing
rolls co-operating with the rolls of the mandrel.
It further comprehends the employment of a series of roller mandrels of the fore-
going character, in combination with a series of sets of external compressing rolls
respectively operative in connection with given mandrels, when the arrangement is
such that the rolls of a given mandrel and those of a corresponding set of external
compressing rolls are set in alternation, interdisposed, or staggered, so to speak, with
respect to the corresponding rolls of an adjacent mandrel and its set of external
compressing rolls. It further comprehends the provision in a machine of the fore-
going organization of driving gearing for at will positively driving the rolls of a set
or sets of external compressing rolls, but it does not exclude the employment of external
compressing rolls which are idlers driven by the friction of the ingot under passage.
It further comprehends the provision of suitable mechanism for simultaneously
advancing towards a common centre all of the rolls composing a given set or sets of

page_text: external compressing rolls; and it, finally, comprehends the provision of suitable
devices for supporting and feeding the ingot to and from the mandrels and their
associated compressing rolls.
It may be premised that after the first pass the external compressing rolls chiefly
effect the consolidation and extension of the ingot by compression of the substance
of its external walls, and that the rolls of the mandrel or mandrels co-operate therewith
by supporting the substance of the internal walls or bore of the ingot against the
compressing thrust of said external rolls, and in driving or feeding it along, but
do not in themselves after said first pass further compress the substance of the ingot.
It is proper also to state that, although the inventor of the same, I do not herein
claim or seek to cover a roller mandrel the rolls of which are positively driven.
Machinery embodying a good form of my invention is represented in the accom-
panying drawings and described in this specification, the particular subject matter
claimed as novel being hereinafter definitely specified.
In the drawings,
Figure 1 is a central, vertical, longitudinal, side sectional elevation in the planes
of the dotted lines - of figure 4, y-y of figure 5, and w-w of figure 6, of the
entire machine the mandrel head and rod being shown in elevation.
Figure 2 is a side elevation of the said machine.
Figure 3 is an elevational detail of one of the external compressing rolls and its
supporting roll frame removed from its frame way.
Figuro 4 is a top plan view of the machine represented in figures 1 and 2.
Figure 5 is a left hand end elevation of the machine represented in figures 1
and 2.
Figure 6 is a transverse sectional elevation through the said machine in the plane
of the dotted line z-z of figure 2.
Figure 7 is a fragmentary plan view of one of the roll frames for carrying a
comprossing roll, the slotted frame ways in which said roll frame is set for movement
being shown in section.
Figure 8 is a right hand end elevational view of the gearing shown in figures 1, 3
and 4, which constitutes a prime mover for the mandrel rack.
Figure 9 is a diagram illustrative of the application of my invention to machinery
for rolling a hexagonal tube.
Figure 10 is an end elevational view of one of the roll standards and idler carrying
rolls for supporting the ingot.
Figure 11 is a sectional plan of the same in the plane of the dotted line u―u upon
said figure 10.
Figure 12 is a fragmentary sectional detail through a portion of the standard frames,
adjusting ring, a roll framio, and an adjusting wheel.
Figure 13 is a fragmentary sectional elevation of one of the divided roll shafts in
the region of its clutch.
Similar letters of reference indicate corresponding parts.
The machine represented in the foregoing drawings is one which is provided with
a double roller mandrel, that is to say with two roller mandrels in the same longi-
tudinal line, and each having three positively driven rolls respectively by mandrels
staggered or alternated as shown, and which is also provided with two sets of external
compressing rolls operating respectively in conjunction with the rolls of the respective
mandrels and, as in the case of said last mentioned rolls, respectively by sets staggered
or alternated as shown.
I illustrate and hereinafter describe the foregoing machine because it is one well
adapted to effectuate my invention, but I wish it to be understood that my invention
comprehends mechanisms of other and different organizations.
Thus for example, instead of employing two mandrels and two sets of compressing
rolls, but one mandrel and one set of compressing rolls, or more than two mandrels
and a correspondingly increased number of sets of compressing rolls, may be employed.
Thus also, instead of employing three rolls in each mandrel, and three external
compressing rolls in each set, but two, or more than three rolls may be used in each

page_text: mandrel and, correspondingly, but two or more than three rolls used in each set of
external rolls.
As the mandrel employed is an essential member of the organization embodying
my present invention, and notwithstanding that it per se, constitutes the subject
matter of a separate application for patent, it is important for me to describe it, in
order that this machine in its entirety may be understood.
The mandrel employed relates to a class of mandrels in which the head, ball, or
mandrel proper, is provided with two, three, four, five, or more, usually ellipsoidal
friction rolls mounted in bearings in a stock or case, and adapted to be introduced
within the tube to be rolled: Types of mandrels of the foregoing class, which fire of
my invention, are to be found in United States Letters Patent No. 151,323, dated
May 26th, 1874; and No. 331,570, No. 331,573, and No. 331,578, all dated
December 1st, 1885,-to which Letters Patent reference is to be made for the better
understanding of my present improvements..
The intention of the employment of mandrels of the foregoing class, it may be
premised, is to obviate friction between the interior surfaces of the tube and the ball
of the ordinary mandrel, and to permit of the more ready passage of the tube over
the mandrel, and withdrawal of the mandrel from the tube.
The object of my improvement in roller mandrels set forth in my application for
patent referred to, is to provide means for positively driving mandrel rolls so as to
render them no longer idler rolls the movement of which is wholly due to the move-
ment of the tube upon them, but positively driven rolls which move under the thrust
or impulse of suitable actuating devices with a positive rotative motion which is the
same as, or greater, or less, than, that of the tube operated upon. To such end my
said invention referred to, broadly stated, comprehends the provision in connection
with the rolls of a roller mandrel of driving gearing of any preferred character,-
and substantially, for instance, of any such character as is represented in the accom-
panying drawings of this application and hereinafter referred to,-which is disposed
between the mandrel rolls with which it is engaged, and a prime mover of any
preferred character with which it is also engaged, and which receives its move-
ment from said prime mover and transmits to said rolls, the arrangement as
an entirety being substantially such that the connective gearing, be its specific
mechanical character what it may, operatively unites the prime mover and the
mandrel rolls and imparts to said rolls a positive movement transmitted direct from
said prime mover.
Such being the general character of my invention referred to, it is apparent that
the form of the gearing intermediate between the prime mover and the driven rolls
may structurally vary and assume the form of many well known mechanical move-
ments, and that. the prime mover may likewise vary and be a motor of any suitable
character.
In the double mandrel represented in the drawings, A A A represent the three
mandrel rolls which are contained and journalled in the first mandrel head B,
and A* A* A* the three mandrel rolls which are contained and journalled in the
second mandrel head Bx. The two mandrel heads are both secured together in
alignment as shown, and carried upon the extremity of the mandrel rod C, supported
from and by a mandrel standard D, erected from the bed plate E.
The rolls of both mandrel heads are respectively centrally circumscribed by sunken
teeth a a*, and the driving gearing of, and which is common to, both sets of rolls is
constituted by a rack F having six independent lines or series of teeth f, adapted by
lines respectively to engage with the respective series of sunken teeth upon the
respective mandrel rolls.
A convenient prime mover for occasioning the thrust of the aforesaid rack in
either direction, is the following:-
The mandrel standard D, is provided with a standard bracket D*, which, in
connection with said standard, presents bearings for a prime mover shaft d the inner
extremity of which is equipped with a rack pinion d' engaged with the rack, and is
also equipped with a spur wheel d'engaged with a counter spur wheel d³ upon a

page_text: pinion shaft d which is between its bearings on the mandrel standard provided with
a counter pinion d' also engaged with the rack.
At its outer extremity the prime mover shaft d is provided with a bevel pinion d
which gears with a sister pinion d' right angular thereto and connected with a minor
pinion shaft do which below its bearing in the bracket D* is equipped with a driven
bevel pinion do engaged with a driving pinion do on the near extremity of a counter
shaft G extending longitudinally of the machine, and at its far extremity equipped
with a minor pinion g engaged with a master pinion g* keyed upon the roll shaft h³,
whereof hereinafter, from which the rotation of the counter shaft is derived.
It is obvious that the rotation of the counter shaft will, according to its direction,
through the intermediate bevel gearing described, occasion the rotation of the prime
mover shaft d in one or the other direction, and that said last named Shaft will through
the spur wheels and the pinions d¹ d³ occasion the propulsion of the rack in one
or the other direction.
While the foregoing contrivances as a connected wholo constitute a convenient
prime mover for actuating a rack which happens to be the driving gearing employed
to occasion the driving of the mandrel rolls, it is obvious that other mechanical
contrivances may be substituted for the same purpose.
It is also apparent that the thrust of the rack in either direction will occasion the
simultaneous and similar rotation of all of the mandrel rolls.
As already explained, the foregoing devices, which essentially compose a roller
mandrel having positively driven rolls, driving gearing for the same, and a prime
mover for said gearing, constituto the subject matter of my application for patent
referred to, and are not in themselves claimed herein.
The external compressing rolls HH H, being those of the first set operative in
conjunction with the rolls A of the first mandrel head, and I I I, being those of th
second set operative in conjunction with the rolls of the second mandrel head, are
constructed, housed, arranged, and operated in substantially the following manner :-
J is a housing or standing frame for supporting the rolls H of the first set.
K is a
housing or standing frame for supporting the rolls I of the second set.
The two standing frames or housings are conveniently parallel, erected from the
bed plate, fastened, stayed or tied together as convenience of manufacture may
dictate, and preferably of the form shown in the drawings, that is to say, open
centred for the location of the mandrel heads within them and for the passage of the
ingot through them.
Each of these frames serves to support or carry the external compressing rolls of
one of the two sets of rolls, and to such end each of the said frames is preferably of
skeleton form, embodies internally radially projecting frameways, j, k, which sustain
the roll frames hi which respectively carry the respective compressing rolls H
and I.
The roll frames detached are represented in figures 3 and 7, and they each consist
of a yoke or cross head, to which the letters hi are respectively applied, and of side
bars hi which are formed or provided with any suitable boxings or bearings for
the gudgeons or axles of the rolls.
In the form of machine represented, one (the lower in the first set and the upper
in the second set) of the rolls of each set of rolls is mounted horizontally, while its
two neighbors in the same set are mounted obliquely at its sides as shown in figures 5
and 6 of the drawings. The gudgeons of the lower roll H of the first set are
constituted by a roll shaft 3, and similarly the gudgeons of the upper roll I of the
second set are constituted by a roll shaft 2.
Each of these roll shafts is horizontal and the two shafts are parallel. These
shafts as shown in figures 3, 4, 5, and 6, are extended through suitable bearings in
the roll frames to the right hand thereof, and are equipped respectively with roll
shaft spur wheels h³ ³ which engage with each other as best shown in figure 3.
Each of these roll shafts is conveniently a divided shaft (or, so considered, two
shafts) provided respectively in the region of their division with clutches h* * of any
preferred character, preferably one fixed and one sliding as shown in figure 13,

page_text: which, according as they are respectively in bite or out of bite with each other,
render the divisional members of the shafts to which they are respectively applied
integral or capable of receiving throughout their entire length the motion imparted
to them by the movement of the spur wheels which they respectively carry, or else
divided, the outer portions to which the spur wheels are applied alone being positively
driven by said spur wheels, while the inner portions which carry the compressing
rolls are not for the time being driven at all but adapted to run idle within their roll
frames.
The inner chambers of each of the aforesaid divided roll shafts are respectively
provided each with a pair of long leaved bevel pinions, figures 4 and 5, keyed
upon them, each of which pinions of the aforesaid pair of pinions is engaged with a
corresponding counter bevel pinion 1 respectively mounted upon the extended
gudgeon of that compressing roll which, in either set of rolls, is contiguous or adjacent
to the aforesaid bevel pinion or i, as the case may be..
It is obvious that the application of the foregoing pinions to the respective rolls
occasions the positivo gearing together of all of the rolls constituting a given set, and
that when the clutches on the divided roll shafts are in bito, rotation imparted to said
roll shafts and consequently to the bevel pinions and compressing rolls which these
shafts respectively carry, is also, through the counter bevel pinions, imparted to each
of the other two pair of rolls which respectively complete the respective sets.
It is, moreover, obvious from consideration of the gearing aforesaid that the positive
rotation imparted to all of the compressing rolls is in the same direction as to all of
said rolls.
The foregoing gearing, considered as a connected whole, is simply a type of driving
gearing well adapted to actuato to a positive common rotation all of the rolls of the
sets of rolls employed, but it is obvious that other driving gearing operative to the
same result would constitute the mechanical equivalent of the gearing specified.
Any prime mover may be employed to impart rotation in either direction to the
aforesaid driving gearing of the compressing rolls. I prefer to employ as a
convenient prime mover a motor shaft L, figures 2, 5, and 6, conveniently housed in
the standing frame K, to which rotation in either direction is by any preferred means
imparted, and which is provided with a motor pinion set to engage the roll shaft
spur wheel or that spur wheel which drives the roll shaft 2 of the first set of
external compressing rolls H.
Instead, however, of the foregoing, which is recommended for its simplicity, other.
forms of prime mover may be employed.
It will now be apparent that the bevel gearing g g* respectively connecting the
roll shaft and the counter shaft G, is operative, through the intermediation of tho
prime mover for actuating the driving gearing of the rolls of the mandrel to occasion
a positive connection between the gearing for driving the external compressing rolls
and the driving gearing of the rolls of the mandrel,-and that therefore the motor
shaft L and its motor pinion constitute not only a prime mover for the gearing
which, when the clutches throw it in action, drives the compressing rolls, but also a
master prime mover for, through the intermediary prime mover and gearing
described, actuating the rolls of the mandrel.
It is now to be understood that, although the positive connected driving of the
compressing rolls is that mode of operation which I prefer to employ, yet that such
driving may be dispensed with, the mandrel rolls alone being positively driven, and
that, in such employment, the bevel and counter bevel pinions of the compressing
rolls, while in fact idlers, to be dispensed with if desired, yet, when retained, constitute
a positive connection between the rolls of each set and serve to secure uniformity in
their movement.
In practice I prefer that the working belly of each compressing roll should be
struck upon a radius slightly greater than the radius of the working face of the
corresponding roll of the mandrel, and consequently upon a radius slightly greater
than that of the exterior of the ingot intended to be reduced and this because it is of

page_text: advantage that the greater part of the work should be performed by the central
portion of the belly of the compressing rolls, and because such shape allows the
surfaces of the ingot near the ends of the compressing rolls to slip laterally to some
extent whereby buckling is avoided.
The extremities of the compressing rolls are, as shown, preferably edgod-off,
rounded, or flattened into a practically cylindric continuation of the rolls, and this is
done to prevent the edges of the rolls, if sharp, from embedding themselves in the
ingot and making marks difficult of obliteration.
In the practice of the manufacture which my invention is designed to effectuate, it
is usually necessary to cause the ingot to pass more than once, and first in one
direction and then in the other, through the rolls, and to this end it is important to
provide, upon each side of the rolling mill proper, suitable devices for carrying and
supporting the ingot, and also to provide convenient means for, after each pass,
setting up toward a common centre and to a predetermined extent, all of the rolls
which constitute the respective sets of compressing rolls.
The foregoing objects I conveniently carry out by the following contrivances,
which are simply typical of many others equally well adapted to subserve the
purpose:
M are a series of idler carrying rolls,-any desired number of which may be
arranged in the line of the pass of tho ingot on each side of the rolling mill proper.
Each of these rolls is supported upon a roll standard m of any preferred character,
and such, for instance, as that represented in figures 10 and 11 of the drawings, and
is journalled in a yoke mx adapted to the standards or to ways mt formed therein.
The yoke of each carrying roll is fixedly provided with a depending lifting screw m¹
passing freely vertically downward through orifices in parallel horizontal cross webs m²
being parts of the standard, between which webs is housed against up or down play
a driven sprocket wheel m³ axially threaded upon the lifting screw m¹ in connection
with which it operates. It is apparent that when said driven sprocket wheel is
rotated, the webs between which it is housed resisting vertical thrust, it will,
according to the direction of its rotation, occasion the raising or the lowering of the
lifting screw and its connected yoke and carrying roll.
In the drawings I have shown but two carrying rolls disposed upon the mandrel
end of the mill. It is to be understood however, that some such rolls are to be
applied at both ends of the machine, and that the number employed is to be such as
to permit of the convenient handling of ingots and tubes of considerable length.
The below described devices constitute a convenient means for effectuating the
common adjustment toward a common center of the rolls constituting the sets of
external compressing rolls. They are not, of course, the only means which may
be employed, but they are effectual for the purpose and inexpensive. They are
theso:-
N is what I term an adjusting ring, it being an annular body provided with a
peripheral series of worm teeth n*, and with rack teeth n in circular series upon
each of its side faces.
The ring is also, but for convenience merely, provided with an internal circular
track n², by means of which it the said ring is mounted and rides upon flanged
carrying rollers n³ suitably supported in any preferred manner, as, for instance,
by means of brackets n as represented in figure 1, from the standing frames.
The adjusting ring, being so, as aforesaid, mounted for rotatory movement with
respect to its carrying rollers, is, at will, actuated to such movement by a worm 0,
figure 6, housed in suitable bearings erected from the framing, and mounted upon
worm shaft Ox provided with a hand wheel O for imparting to it, and
consequently to the worm, rotation.
a
Each of the housings or standing frames J, K, is radially to the outside of or
beyond its frame ways, and in line therewith, formed with slots or openings
respectively as to said frames designated jx and k*, and in each of these slots is
snugly housed a toothed adjusting wheel P P*, the wheels P being those in the

page_text: screw
first standing frame J and the wheels Px those in the second K. All of these
adjusting wheels are axially threaded and mounted upon radial adjusting screws
respectively designated Q Qx, and housed free for endwise movement in
ways correspondingly designated 79*. At their inner extremities the adjusting
screws are respectively fixedly connected with the roll frames, as shown in
figures 1, 5, 7, and 12. Inasmuch as each of the adjusting wheels is accurately
fitted against radial play within its slot, it is apparent that rotation imparted to
said wheels will, through the adjusting screws in connection with which they
operate and according to the direction of such rotation, impart an inward or
outward radial movement to the roll frames with which said screws are connected
and consequently to the external compressing rolls with which said frames are
equipped.
The rotation of the adjusting wheels is accomplished by movement imparted to the
adjusting ring N, the rack teeth n on its sides respectively engaging with the several
adjusting wheels P and P*, as clearly shown in the drawings.
It will now be understood how, after a given pass of the ingot in either direction
has been made, the external compressing rolls may be, by a simple turn of the hand
wheel O, together set up a sufficient distance to exert upon the ingot, upon its next
return or reverse pass, a further compressing action.
In order to, simultaneously with the setting-up of the external compressing rolls,
elevate to a predetermined extent the idler carrying roils so as to adapt them to
properly present or level and support the ingot for the next pass after it has lost
diameter by such reduction as is occasioned by any given pass, I gear the said rolls
together by the employment of sprocket chains R R* which not only engage the
driven sprocket wheels m³ located in the standards of the carrying rolls but also
driving sprocket wheels S S*, of which S, which is that driving the chain R, is directly
connected with the lowermost adjusting wheel P of the lowermost roll of the standing
frame J, and of which S, which is that directly connected with the chain R*, is
connected with a supplemental adjusting wheel T, housed in the lower portion of the
second standing frame K upon a fixed gudgeon t secured in said frame."
It is of course apparent that while the foregoing is a convenient contrivance for
simultaneously adjusting both the external compressing rolls and the idler carrying
rolls, other mechanical contrivances may be substituted in its stead. The devices
described are simply a convenient connecting gearing for the purpose.
In figure 9, I have represented an arrangement to which resort may be had for the
purpose of rolling hexagonal tubes. Three external compressing rolls of cylindrical
contour and of length equal to the breadth of the facets of the hexagon are applied
respectively to the three alternate sides of the hexagon, and with them is used a
positively operated roller mandrel which presents its three conico-cylindric operating
rollers to the inner faces of the same sides of the ingot as the external rolls are
operating upon. As is obvious, upon a second pass the three sides of the ingot which
are not operated upon in the first pass will be upon its rotation presented to the rolls.
I have deemed it unnecessary to represent in connection with these rolls the connected
mechanism necessary to drive them, but it will be understood that the said rolls may
be operated by machinery of the same general character as that illustrated and
described in connection with the other various forms of rolls. And also understood
that by corresponding modifications of the rolls, tubes of other sectional outline may
be produced.
In all of the drawings the ingot is designated by the letter W.
Having now described a good form of apparatus embodying my invention it is
proper to state that all gearing for driving the external compressing rolls may be
dispensed with and such rolls be simply idler rolls; and proper also to state that,
while I prefer to use three external compressing rolls to the set, and two sets the
respective rolls of which are interdisposed, because by such arrangement I secure an
equal circumferential pressure upon all portions of the ingot and at, the same time
secure sufficient room between the rolls to afford good bearings for their axles, yet

page_text: that but one set of rolls may be employed, and the tube after each pass be turned to a
sufficient extent to, upon the second pass, present the surfaces not in the first instance
subjected to the action of the rolls, to be rolled; and moreover to state that instead of
causing the ingot to travel backward and forward through given sets of rolls a
sufficient number of additional sets may be employed to compass the requisite reduction
at a single pass.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare what I
claim is :-
1. In a rolling mill, the combination of a roller mandrel having two or more mandrel
rolls, gearing for positively driving said rolls, a prime mover for actuating said gearing,
and external compressing rolls, substantially as set forth.
2. In a rolling mill, the combination of a roller mandrel having two or more
mandrel rolls, gearing for positively driving said rolls, a prime mover for actuating
said gearing, external compressing rolls, gearing for positively driving said com-
pressing rolls, and a prime mover for actuating said gearing, substantially as set
forth.
3. In a rolling mill, the combination of a roller mandrel having two or more
mandrel rolls, gearing for positively driving said rolls, a prime mover for actuating
said gearing, external compressing rolls, and adjusting gearing for simultaneously
setting up toward a common centre all of the external compressing rolls, substantially
as set forth.
4. In a rolling mill, the combination of a roller mandrel having two or more mandrel
rolls, gearing for positively driving said rolls, a prime mover for actuating said
gearing, external compressing rolls, gearing for positively driving said compressing
rolls, a prime mover for actuating said gearing, and adjusting gearing for simulta-
neously setting up toward a common centre all of the external compressing rolls,
substantially as set forth.
5. In a rolling mill, the combination of a roller mandrel having two or more mandrel
rolls, gearing for positively driving said rolls, a prime mover for actuating said
gearing, external compressing rolls, and idler carrying rolls for carrying and
supporting the ingot, substantially as set forth.
6. In a rolling mill, the combination of a roller mandrel having two or more
mandrel rolls, gearing for positively driving said rolls, a prime mover for actuating
said gearing, external compressing rolls, adjusting gearing for simultaneously setting
up toward a common centre all of the external compressing rolls, idler carrying rolls
for carrying and supporting the ingot, and adjusting gearing for adjusting the vertical
set of said carrying rolls, substantially as and for the purposes set forth.
7. In a rolling mill, the combination of a roller mandrel having two or more mandrel
rolls, gearing for positively driving said rolls, a prime mover for actuating said gearing,
external compressing rolls, gearing for positively driving said compressing rolls, a
prime mover for actuating said gearing, adjusting gearing for simultaneously setting
up toward a common centre all of the external compressing rolls, idler carrying rolls
for carrying and supporting the ingot, and adjusting gearing for adjusting the vertical
set of said carrying rolls, substantially as and for the purposes set forth.
8. In a rolling mill, the combination of a series of roller mandrels each containing
two or more rolls, the rolls of said respective mandrels being alternated or inter-
disposed as set forth,-gearing common to the rolls of all of the mandrels for positively
driving said rolls, a prime mover for actuating said gearing, and a series of sets of
external compressing rolls corresponding in number with the mandrels, the rolls of
said respective sets being alternated or interdisposed as set forth and operating

page_text: respectively in connection with corresponding rolls of corresponding mandrels,
substantially as. set forth.
9. In a rolling mill, the combination of a series of roller mandrels each containing
two or more rolls, the rolls of said respective mandrels being alternated or inter-
disposed as set forth,-gearing common to the rolls of all of the mandrels for
positively driving said rolls,-a prime mover for actuating said gearing, a series of
sets of external compressing rolls corresponding with the number of mandrels, the
rolls of said respective sets being alternated or interdisposed as set forth and operating
respectively in connection with corresponding rolls of corresponding mandrels,-
gearing for positively driving said compressing rolls, and a prime mover for
actuating said gearing,-substantially as set forth..
10. In a rolling mill, the combination of a series of roller mandrels each containing
two or more rolls, the rolls of said respective mandrels being alternated or inter-
disposed as set forth,-gearing common to the rolls of all of the mandrels for
positively driving said rolls, a prime mover for actuating said gearing,-a series of
sets of external compressing rolls corresponding with the number of mandrels,--the
rolls of said respective sets being alternated or interdisposed as set forth and operating
respectively in connection with corresponding rolls of corresponding mandrels, and
adjusting gearing for simultaneously setting up toward a common centre all of the
compressing rolls of all of the sets,-substantially as set forth.
11. In a rolling mill, the combination of a series of roller mandrels each containing
two or more rolls, the rolls of said respective mandrels being alternated or inter-
disposed as set forth,-gearing common to the rolls of all of the mandrels for
positively driving said rolls, a prime mover for actuating said gearing, a series
of sets of external compressing rolls corresponding with the number of mandrels,
the rolls of said respective sets being alternated or interdisposed as set forth and
operating respectively in connection with corresponding rolls of corresponding
mandrels, gearing for positively driving said compressing rolls,a prime mover for
actuating said gearing, and adjusting gearing for simultaneously setting up toward
a common centre all of the compressing rolls of all of the sets,-substantially as
set forth.
12. In a rolling mill, the combination of a series of roller mandrels each containing
two or more rolls, the rolls of said respective mandrels being alternated or inter-
disposed as set forth,-gearing common to the rolls of all of the mandrels for
positively driving said rolls, a prime mover for actuating said gearing,-a series
of sets of external compressing rolls corresponding with the number of mandrels,
the rolls of said respective sets being alternated or interdisposed as set forth and
operating respectively in connection with corresponding rolls of corresponding
mandrels, an idler carrying rolls for carrying and supporting the ingots,―
substantially as set forth.
13. In a rolling mill, the combination of a series of roller mandrels each containing
two or more rolls, the rolls of said respective mandrels being alternated or inter-
disposed as set forth,-gearing common to the rolls of all of the mandrels for
positively driving said rolls,- -a prime mover for actuating said gearing,-a series of
sets of external compressing rolls corresponding with the number of mandrels, the
rolls of said respective sets being alternated or interdisposed as set forth and operating
in connection with corresponding rolls of corresponding mandrels, adjusting gearing
for simultaneously setting up toward a common centre all of the external compressing
rolls,-idler carrying rolls for carrying and supporting the ingot, and adjusting
gearing for adjusting the vertical set of said carrying rolls, substantially as set forth.
14. In a rolling mill, the combination of a series of roller mandrels each containing
two or more rolls, the rolls of said respective mandrels being alternated or inter-
disposed as set forth,-gearing common to the rolls of all of the mandrels for
positively driving said rolls,-a prime mover for actuating said gearing, a series of
B

page_text: sets of external compressing rolls corresponding with the number of mandrels, the
rolls of said respective sets being alternated or interdisposed as set forth, and operating
in connection with corresponding rolls of corresponding mandrels,-gearing for
positively driving the sets of external compressing rolls,-a prime mover for actuating
said gearing, adjusting gearing for simultaneously setting up toward a common
centro all of the external compressing rolls,-idler carrying rolls for carrying and
supporting the ingot, and adjusting gearing for adjusting the vertical set of said
carrying rolls, substantially as set forth.
1000