Improvements in Machines for Rolling Seamless Metal Tubes or like Hollow Articles from Hollow Ingots
Year: 1890

page_text: Date of Application, 24th Oct., 1890
Complete Specification Left, 21st July, 1891-Accepted, 10th Oct., 1891
PROVISIONAL SPECIFICATION.
Improvements in Machines for Rolling Seamless Metal Tubes or
like Hollow Articles from Hollow Ingots.
A communication from abroad by CHARLES KELLOGG, of the City, County, and
State of New York, United States of America.
I, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of the Agency for
Foreign Patent Solicitors, 6, Lord Street, Liverpool and 6, Bank Street,
Manchester, both in the County of Lancaster and 323 High Holborn in the County
of Middlesex, Civil Engineer, do hereby declare the nature of this invention to be
as follows:
This invention relates to the manufacture of seamless tubes, pipes and other
tubular or cylindrical articles from hollow steel or other metal ingots, by means of
a machine consisting of a series of pairs of grooved rolls operating in conjunction
with a mandrel located in the passes of the said rolls.
In Letters Patent No. 2933 dated February 19th, 1889 for "Improved method of
and apparatus for rolling seamless tubes and other tubular articles from hollow ingots,"
is shown and described a machine for making tubes, pipes etc., by rolling, reducing
and elongating a hollow ingot of steel or other metal, consisting of a series of pairs
of alternate vertical and horizontal grooved rolls, the successive pairs of rolls being
driven at gradually increasing speed, a mandrel placed between the rolls and centered
in the passes formed by the grooves therein, and separately operated grips for
holding and centering the mandrel, the said grips being controlled and operated by
power and arranged so that when one is open the other is closed, so as to admit of
heated ingots being passed onto the mandrel and thence to the rolls without
decentering or releasing the mandrel. The construction of the said patented
machine is such that tubular articles of but limited sizes can be made on it, say
with a difference of not more than 2 inches between the diameters of the largest and
smallest tubes or pipes than can be made with the machine; hence a special
machine is required for every size outside of this limit that it is desired to inake.
As pipes and tubes in common demand vary greatly in size, to supply the market,
a factory would have to be equipped with a separate machine for every size of tube
greater than the 2 inches above the smallest size of tube a single machine is capable
of making.
To obviate this objectionable feature of the patented machine is the object of the
present invention, which consists first, in the construction and adaptation to the
driving mechanism of a rolling mill of several series of pairs of rolls, each of said
series being adapted to produce tubes of a different size.from the other series and
said several series being interchangeable one with another or either of the other
series whereby a single rolling mill plant is adapted to produce different sizes of
tubes by merely changing the rolls; second, in sets or pairs of rolls for producing
tubes, pipes etc., of various sizes that may be driven by the same system of gearing,
the construction of the said rolls, being such that, the several pairs that have
grooves of different areas for rolling tubes, etc., of different diameter, but each
designed to occupy the same place in the machine, have the same or approximately
the same diameter at the point of the pass where the greatest resistance is met
with, so that at this point each of the sets of roils will have the same or approxi-
mately the same speed, that the ingot has from elongation due from reduction of
sectional area by the preceding rolls and thus whatever the diameter of the ingot
may be for different sizes of pipe the rate of reduction and elongation at any one
pair of rolls of the system will be the same whatever may be the area of the grooves
or pass.

page_text: nature of the
The following detailed description will serve to illustrate the
invention, although it is to be distinctly understood that the invention is by no
means limited to the exact details set forth in such description.
a foundation of solid masonry and
The bed plate of the machine is laid on
Columns rest on the bed
secured thereto by anchor bolts in the usual manner.
plate and support the housings floor. Between the bed plate and housings floor is
placed the gearing for driving the vertical rolls-while the gearing that drives the
horizontal rolls is placed in a framework built on the housings floor. The gearing
of the vertical rolls is connected with vertical shafts that are supported in suitable
bearings on the bed plate and floor, and the shafts for the gearing of the horizontal
rolls is held in suitable bearings in the framework. The vertical rolls are driven
from the engine shaft by any suitable gearing.
The several shafts of the vertical rolls are connected together by a series of
wheels and pinions to give a surface speed at the bottom of the grooves in the several
rolls equal to the elongation of the ingot by the reduction made by each preceding
pair of rolls.
The vertical shafts are coupled alternately with the right and left hand rolls of
the vertical series and thus the said rolls are driven directly by the said shafts,
while the uncoupled rolls are geared to the coupled rolls by toothed wheels and
thus the rolls of each pair are driven positively. The successive pairs of rolls
commencing with the first pair are driven at gradually increasing speed to com-
pensate for the increasing length of the ingot as it is reduced in its progress
through the rolls.
The horizontal rolls are driven from a pinion on the counter shaft by suitable
gearing. The horizontal shafts are coupled alternately to upper and lower rolls,
counting from the front of the machine, and the rolls of each pair being geared
together by toothed wheels. The gearing of the horizontal rolls is likewise
arranged and proportioned to give a gradually increasing speed to the successive
pairs of rolls.
The several pairs of rolls are readily adjustable relatively to each other; con-
sequently the axis of the pass in each and every pair may be made to coincide
with the axis of the passes in the remaining pairs, so that a line drawn through
the centre of the passes of the first and last pairs of rolls will be the centre of
the
pass of every pair of rolls in the series.
The vertical rolls that are not coupled to the gearing shafts are coupled
underneath to upright journals, which are held in suitable bearings.
The rolls of both the vertical and horizontal series which are driven directly from
the vertical and horizontal shafts are connected with said shafts by means that permit
the axis of rotation of said rolls to be changed at will, so that rolls of different
outside diameters may be operated in the same machine and by the same gearing
and shafts and also be adjusted readily to the rolling positions. The means used
for this purpose are contrivances that connect, by means of coupling sleeves, the
gearing shafts, with the roll shafts, and in such a manner that whether or not
the axes of the rolls coincide with those of the shafts, these contrivances will com-
These contrivances are
municate the rotary motion of the shafts to the rolls.
wabblers which have one. end held in a sleeve coupling on the vertical and
These
horizontal shafts and their opposite ends in couplings on the roll shafts.
wabblers should have their ends formed in such a manner that whatever their
angular position with respect to the shafts and the rolls they will continue in
engagement with the couplings and will transmit the motion of the shafts to the
rolls. For this purpose the ends of the wabblers are provided with oppositely
beveled faces and they are also grooved in the usual manner of the coupling ends
of roll shafts by which they are adapted to connect with the sleeve couplings.
The grooves at the ends of the wabblers are also beveled to correspond to the
beveled faces of the ends. By this construction the wabblers transmit the rotary
motion of the vertical and horizontal shafts to the rolls with which they are
coupled whether the rolls are centered with the shafts or decentered in any

page_text: direction that does not destroy the parallelism of the axes of the rolls and the shafts.
The wabblers can assume various positions with respect to the axes of the rolls and
the gearing shafts for the purpose of accommodating rolls of different diameters
and in these positions they transmit the power and motion of the gearing shafts to
the rolls.
or
At the points in the pass between the rolls where the greatest resistance to the
reduction of the ingot is met with, a gearing is adjusted to the action of the rolls.
Therefore, when the gearing is adjusted to give a pair of rolls of a given diameter
at the bottom of the groove a certain speed, other rolls, having the same
approximately the same diameter at that point, may be used in the same machine
with the same system of gearing, notwithstanding that they may be of greater or
less diameter at other points outside of the bottom of the grooves, as for example
in the part of a roll called the barrel, and their action on the ingot undergoing
reduction and elongation will be the same. Where rolls of various sizes of barrels
are to be used with the same machine, to make different sizes of pipe, all those
intended for the same position in the machine must have the same diameter at the
bottom of the grooves.
The shape of the passes in the rolls may be circular or alternately circular and
elliptical, or all may be elliptical, but with the major axes of the elliptical pass in
one set of rolls at an angle (say at right angles) to the major axis of the elliptical
pass in the adjacent pair of rolls. Preferably where these forms are used,
the vertical rolls should have the elliptical passes, and the horizontal rolls the
circular.
The mandrel consists of a steel rod which may be made in one piece or in
sections, the two sections being coupled together by a screw block which at its
larger end is screwed to the stock of the mandrel. On the mandrel rod are placed
at intervals, equal to the distance between the centres of adjacent pairs of rolls,
balls or sections that form the interior bearing surfaces or supports for the walls
of the ingot while undergoing reduction. The balls are spaced and held in position
by sections of pipe placed on the rod between the balls, the balls and tubes being
held on the rod by a jam nut screwed on the end of the mandrel rod. When the
balls are alternately elliptical and round in cross section the passes in the rolls
should correspond in shape to the balls so that the walls of the passes and balls
will be parallel, hence when the ingot which at the beginning is round in cros
section, passes between the elliptical ball and the corresponding elliptical pass, it is
brought to an elliptical form, its walls being reduced to the thickness of the space
between the ball and the walls of the pass. At the next pair of rolls it is brought
to a circular or cylindrical form, then at the next to an elliptical form and so on
alternately until the last pair of rolls is reached which gives the final form to the
ingot and from which it passes a finished tube. When all the balls are cylindrical,
passes of the rolls are alternately circular and elliptical, so that the ingot at the
first pair of rolls is rolled so that its exterior form becomes elliptical, while the
forin of its inside wall remains round, the surplus metal being forced away from
the sides and into the parts in line with the longer axis of the ellipse. At the next
pair of rolls the ingot is again. brought to the round form-the pass in the second
set of rolls being round. This alternate rolling from round to elliptical is continued
to the last pair of rolls which gives the final form.
When the mandrel balls are
elliptical but arranged so that the major axes of the alternate balls are at angles
to each other the passes of the pairs of rolls for the balls must correspond in shape
and position with the balls placed in the passes.
The object of rolling the ingot alternately round and elliptical is to facilitate the
reduction of the ingot and its elongation into a tube.
The stock of the mandrel is provided with corrugated surfaces formed in any
suitable way as by cutting deep screw threads in the stock. The purpose of this
is to present to the interior surface of the heated ingot when passed into the stock
a series of sharp edges, which when the ingot is moved forward between the grips
and thence to the rolls will scrape the inside walls of the ingot and free them of

page_text: • sand, scale or other foreign substances before the rolling begins, which would have
a tendency to force such foreign substance into the walls of the tube. Another
object of these corrugations is to reduce the surface of the mandrel stock so that
when the ingots is passed over the stocks, the cooling effects of contact with the
stock shall be as slight as possible.
At proper points the stock is reduced to form grasping points for the jaws of the
grips. These grasping points may be of any suitable shape or construction that
will admit of the jaws of the grips holding the mandrel against being turned
axially. The construction and operation of these grips are fully described in my
correspondent's previous patent. In their operation the stock of the mandrel rod
is held by the grips and when a tube is to be rolled the first pair of grips is
opened, the other pair remaining closed and holding the mandrel, the heated ingot
is then placed on the front end of the mandrel and shoved through the first grip.
The first pair of grips is then closed and the other pair opened (the mandrel being
now held by the first grip) the ingot is shoved through the other grip and thence
fed to the first pair of rolls. Thus the heated ingot is passed through the rolls
without releasing the mandrel from the control of the grips at any time. The valves
that control the pistons that work the grips are so arranged that it is impossible to
open both grips at the same time when the machine is working.
Eight sets or pairs of rolls are referred to as used in this machine, but a greater
or less number may be used if desired.
The mandrel balls or sections must be made to correspond to the different series
of sets of rolls.
Dated this 22nd day of October 1800
Improvements in Machines for Rolling Seamless Metal Tubes or
like Hollow Articles from Hollow Ingots.
A communication from abroad by CHARLES KELLOGG, of the City, County, and
State of New York, United States of America.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for
Foreign Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street,
Manchester, both in the County of Lancaster, and 323, High Holborn, in the
County of Middlesex, Civil 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 the manufacture of seamless tubes, pipes and other
tubular or cylindrical articles from hollow steel or other metal ingots by means
of a machine consisting of a series of pairs of grooved rolls operating in conjunction
with a mandrel located in the passes of the said rolls.
In Letters Patent No. 2,933, dated Feb. 19th, 1889, for improved method of
and apparatus for rolling seamless tubes and other tubular articles from hollow
ingots, is shown and described a machine for making tubes, pipes, etcetera, by
rolling, reducing and elongating a hollow ingot of steel or other metal, consisting
of a series of pairs of alternate vertical and horizontal grooved rolls, the successive
pairs of rolls being driven at gradually increasing speed-a mandrel placed between
the rolls and centered in the passes formed by the grooves therein, and separately
operated grips for holding and centering the mandrel-the said grips being
controlled and operated by power and arranged so that, when one
is open,
the other is closed, so as to admit of heated ingots being passed on to the mandrel
and thence to the rolls without decentering or releasing the mandrel.
The con-
struction of the said patented machine is such that tubular articles of but limited

page_text: DELWEED
the diameters of the largest and smallest tubes or pipes than can be made with the
machine; hence, a special machine is required for every size outside of this limit
that it is desired to make. As pipes and tubes in common demand vary greatly in
size, to supply the market, a factory would have to be equipped with a separate
machine for every size of tube greater than the 2 inches above the smallest size of
tube a single machine is capable of making.
To obviate this objectionable feature of the patented machine is the object of
the present invention, which consists, first, in the construction and adaptation to the
driving mechanism of a rolling mill of several series of pairs of rolls, each of said
series being adapted to produce tubes of a different size from the other series and
said several series being interchangeable one with another or either of the other
series, whereby a single rolling mill plant is adapted to produce different sizes of
tubes by merely changing the rolls; second, in sets or pairs of rolls for producing
tubes, pipes, etcetera, of various sizes, that may be driven by the same system of
gearing, the construction of the said rolls being such that the several pairs that
have grooves of different areas for rolling tubes, etcetera, of different diameter, but
each designed to occupy the same place in the machine, have the same or
approximately the same diameter at the point of the pass where the greatest
resistance is met with, so that, at this point, each of the sets of rolls will have the
same or approximately the same speed that the ingot has from elongation due
from reduction of sectional area by the preceding rolls and thus whatever the
diameter of the ingot may be for different sizes of pipe, the rate of reduction and
elongation at any one pair of rolls of the system will be the same whatever may
be the area of the grooves or pass.
The following detailed description will serve to illustrate the nature of the
invention, although, it is to be distinctly understood that the invention is by no
means limited to the exact details set forth in such description.
In the accompanying drawings:-
Figure 1 represents a plan of the machine for rolling seamless pipe, etcetera ;
Figure 2, a side elevation of the same;
Figure 3, a top view, and Figure 4 a side elevation of the pinion gearing for the
horizontal rolls.
Figures 5 and 6 represent the two last pairs of a series of rolls for making large
pipe;
Figures 7 and 8, the same for making medium pipe, and,
Figures 9 and 10, the same for making small pipe, these figures also illustrating
the mechanism for transmitting the motion of the gearing to the rolls.
Figure 11 represents vertical rolls for making large, medium and small pipe, the
three sets being placed together and illustrating the novel construction by which
the several sets of rolls may be used with the same system of gearing.
Figure 12 represents horizontal rolls illustrating the same principle.
Figure 13 represents several pairs of rolls and a mandrel in sectional side
elevation in connection with an ingot undergoing reduction.
Figure 14 represents vertical cross sections of alternate round and elliptical
mandrel sections or balls and the ingot when passing through the machine,
illustrating the reduction of the ingot by said balls.
Figure 14 represents cross sections of an ingot when the passes of the rolls are
alternately elliptical and round, and the mandrel sections are all round in cross
section.
Figure 148 represents a complete mandrel for the tube rolling machine, the balls
and mandrel rod being shown in section.
Figures 14°, 14D and 14 represent cross sections of various forms of mandrel
balls.
Figure 14 represents a side elevation and cross section of the mandrel stock,
the grips for holding the mandrel being represented by broken lines;
Figure 14, a modified construction of the devices shown in Figure 14F, .

page_text: Figure 15 represents a side elevation, and Figures 16 and 17 end elevations, of
the grips for holding the mandrel ;
Figure 18 (Sheet V) a cross section of one of the wabblers, showing the grooves
therein.
Referring to the drawings: --
A, designates the bed plate of the machine, which should be laid on a foundation
of solid masonry and secured thereto by anchor bolts in the usual manner.
Columns rest on the bed plate and support the housings floor F. Between the
bed plate and housings floor is placed the gearing for driving the vertical rolls,
while the gearing that drives the horizontal rolls is placed in a framework W,
built on the housings floor. The gearing of the vertical rolls R is connected with
vertical shafts S, that are supported in suitable bearings on the bed plate and floor,
and the shafts S¹ for the gearing of the horizontal rolls R¹ is held in suitable
bearings in the framework W. The vertical rolls are driven from the engine
shafts by means of a spur wheel 2 (indicated by dotted lines only) that engages
the pinion 3 (also indicated by dotted lines only) on the counter shaft s'.
shaft also carries a bevelled wheel 4 that engages a bevelled pinion 5 on a vertical
shaft 8, which latter also carries a spur wheel 6 that engages a pinion 7 on a
shaft S of the last pair of vertical rolls in the machine.
This
The several shafts S of the vertical rolls are thus connected together by a series
of wheels and pinions 7 to 13, to give a surface speed at the bottom of the grooves
in the several rolls equal to the elongation of the ingot by the reduction made by
each preceding pair of rolls.
The shafts S are coupled alternately with the right and left hand rolls of the
vertical series (this arrangement being indicated in Figure 1 by the dotted lines L
that represent the wheels and pinions on the said shafts) and thus the said rolls are
driven directly by the said shafts, while the uncoupled rolls are geared to the
coupled rolls by toothed wheels 14, 14, and thus the rolls of each pair are driven
positively. The successive pairs of rolls, commencing with the first pair 1, are
driven at gradually increasing speed to compensate for the increasing length of the
ingot as it is reduced in its progress through the rolls. The proportion the gearing
of the several pairs of rolls bears to each other is approximately illustrated in
Figure 4 of the drawings of the Letters Patent above referred to.
The horizontal rolls are driven from a pinion 3 on the counter shaft, the said
pinion transmitting its motion through a series of spur wheels and pinions 15, 16,
17, 18, 19, 20, 21, on the shafts S' coupled to the horizontal rolls in the same
manner as the vertical rolls, the said shafts being coupled alternately to upper and
lower rolls, counting from the front of the machine, and the rolls of each pair
being geared together by toothed wheels. The gearing of the horizontal rolls is
likewise arranged and proportioned to give a gradually increasing speed to the
successive pairs of rolls, the proportion of the gearing being also shown
approximately in Figure 5 of the drawing of the said Patent.
The horizontal rolls R₁ are mounted in upright housings H, and the journal
boxes b are constructed to slide vertically in suitable guides in the housings
adjusting screws 22 bearing against suitable bearers 23 on the upper and lower
boxes being provided to move, adjust to a common centre and sustain the said rolls.
The vertical rolls R are mounted in housing frames H' bolted or otherwise fixed
to the housings H and the boxes b¹ of said vertical rolls are arranged to slide
laterally on suitable guides in the said frames, lateral adjusting screws 22 bearing
on suitable bearers 23, being provided to move, adjust to a common centre and
sustain the said rolls laterally.
By the above described construction and arrangement of the two sets of rolls,
the several pairs are readily adjustable relatively to each other; consequently, the
axis of the pass in each and every pair may be made to coincide with the axis of
the passes in the remaining pairs, so that a line drawn through the centre of the
passes of the first and last pairs of rolls will be the centre of the pass of every pair
of rolls in the series.

page_text: The vertical rolls that are not coupled to the gearing shafts S are coupled
underneath to upright journals J (see Sheets III, IV, V) which are held in suitable
bearings in standards T bolted to the floor F, the journals turning freely in said
bearings.
The rolls of both the vertical and horizontal series which are driven directly
from the shafts S, S₁ are connected with said shafts by means that permit the axis
of rotation of said rolls to be changed at will, so that rolls of different outside
diameters may be operated in the same machine and by the same gearing and
shafts and also be adjusted readily to the rolling positions. The means used for
this purpose are contrivances that connect, by means of coupling sleeves, the
gearing shafts S, SI, etcetera, with the roll shafts, and in such a manner that, whether
or not the axes of the rolls coincide with those of the shafts, these contrivances
will communicate the rotary motion of the shafts to the rolls. These contrivances
are the wabblers 24, which have one end held in a sleeve, coupling 25 on shafts S, S¹,
and their opposite ends in couplings 26 on the roll shafts. These wabblers should
have their ends formed in such a manner that, whatever their angular position with
respect to the shafts and the rolls, they will continue in engagement with the
couplings and will transmit the motion of the shafts to the rolls. For this purpose,
the ends of the wabblers are provided with oppositely bevelled faces f f¹, and they
are also grooved (as shown by the cross sectional view, Figure 18) in the usual
inanner of the coupling ends of roll shafts by which they are adapted to connect
with the sleeve couplings. It will be observed that the grooves at the ends of the
wabblers are also bevelled to correspond to the bevelled faces of the ends. By
this construction, the wabblers transmit the rotary motion of the shafts S, S' to
the rolls with which they are coupled, whether the rolls are centered with the shafts
or decentered in any direction that does not destroy the parallelisin of the axes of
the rolls and the shafts.
Each of the sets of two pairs of vertical and horizontal rolls represented on
Sheets III, IV, V, may be taken to represent the two last pairs of rolis of a
machine adapted to make but one size of pipe, so that, if used in the ordinary
manner, three distinct machines would be necessary to employ the said sets of rolls,
but, as this invention contemplates a machine that may be used to make many sizes of
pipes by simply changing the rolls, the said sets of rolls are intended to form parts
of three series of pairs of rolls that are to be used in the same machine to make
three sizes of pipes. For example, Figures 5 and 6 are the final rolls of a series
for making large pipe, Figures 7 and 8 the same of a series for making medium
pipe, and Figures 9 and 10 the same for making small pipe. The series of rolls
consist of alternate vertical and horizontal rolls as heretofore described, geared to
move with increasing velocity. Thus understood, the positions of the wabblers 24,
with respect to the different sizes of rolls and the gearing shafts, may be readily
understood from said figures. Thus, in Figures 5 and 6, representing the final
vertical and horizontal rolls for making large pipe, the wabblers are turned outward
in the vertical set and upward in the horizontal; in Figures 7 and 8, representing
rolls for medium pipe, the wabblers are centered with the gearing shaft and the rolls,
and, in Figures 9 and 10, representing rolls for making small pipe, the wabblers
are directed downward and inward respectively. Thus, it will be seen that the
wabblers can assume various positions with respect to the axes of the rolls and the
gearing shafts for the purpose of accommodating rolls of different diameters, and,
in these positions, they transmit the power and motion of the gearing shafts to
the rolls.
The rolls of both the vertical and horizontal sets that are not connected with
the gearing shafts are also adjustable, the first by means of the standards T, the
fastening bolts of which are passed through slots in the floor, which permit the
standards to be moved laterally, and the second by means of their adjustable
boxes.
The construction of the rolls to adapt those of different diameters to be used in

page_text: 'the same machine will best be understood by reference to Figures 11 and 12, where
The three sets are
three sets of horizontal and vertical rolls are represented.
The rolls
drawn together so that the differences in their size can be clearly seen.
marked r, drawn in solid lines, are for rolling the largest sized pipe, those marked 1
in broken lines are for the medium sized, and those marked in solid lines are for
the smallest sized pipe to be rolled in one machine. The grooves, it will be
observed, vary greatly in area, but the diameter of the rolls at the deepest part
of the grooves (the point a ¹) which may be designated the pitch line of the rolls,
for all three rolls, is the same, and, therefore, the surface speed of all the rolls
at this point, with the same system of driving gear, is the same. Hence, either of
the three sets of rolls r, 1, 1, may be used interchangeably in the same machine,
and at the pitch line x, x¹ their speed will be uniform.
What is above called the pitch lines x, x are the points in the pass between the
rolls where the greatest resistance to the reduction of the ingot is met with, and the
gearing is adjusted to the action of the rolls at this point of their surface. Therefore,
when the gearing is adjusted to give a pair of rolls of a given diameter at the bottom
of the groove a certain speed, other rolls, having the same or approximately the
same diameter at that point, may be used in the same machine with the same
system of gearing, notwithstanding that they may be of greater or less diameter
at other points outside of the bottom of the grooves, as, for example, in the part
of a roll called the barrel, and their action on the ingot undergoing reduction and
elongation will be the same.
By reference to Figure 2, it will be seen that the pairs of rolls are numbered 1
to 8 consecutively, commencing at the front end of the machine, and these numbers
indicate the position of the rolls in the machine or the order of their action on the
ingot. Where rolls of various sizes of barrels are to be used with the same
machine to make different sizes of pipe, all those intended for the same position
in the machine must have the same diameter at the bottom of the grooves.
The shape of the passes in the rolls, may be circular or alternately circular
and elliptical, or all may be elliptical, but, with the major axes of the elliptical
pass in one set of rolls at an angle (say at right angles) to the major axis of the
elliptical pass in the adjacent pair of rolls. The alternately elliptical and circular
forms are shown in Figures 11 and 12, and also in Figures 5 to 10. Preferably,
where these forms are used, the vertical rolls should have the elliptical passes;
and the horizontal rolls, the circular.
The mandrel and mandrel balls or sections are illustrated on Sheets VII, VIII.
The mandrel consists of a steel rod T¹ which may be made in one piece, as in
Figure 13, or in sections T', T", as in Figure 14³, the two sections being coupled
together by a screw block 27. The block at its larger end, is screwed to the
stock 28 of the mandrel. On the mandrel rod are placed at intervals, equal to the
distance between the centres of adjacent pairs of rolls, balls or sections V that
form the interior bearing surfaces or supports for the walls of the ingot while
undergoing reduction. The balls are spaced and held in position by sections of
pipe 29 placed on a rod between the balls, the balls and tubes being held on the
rod by a jam zut 30 screwed on the end of the mandrel rod. The drawings show
various forms of mandrel balls; Figure 14 representing alternate elliptical and
round forms in cross section. In this case, the passes in the rolls should correspond
in shape to the balls V, so that the walls of the passes and balls will be parallel ;
hence, when the ingot I, which, at the beginning, is round in cross section, passes
between the elliptical ball and the corresponding elliptical pass, it is brought to an
elliptical form, its walls being reduced to the thickness of the space between the
ball and the walls of the pass. At the next pair of rolls, it is brought to a circular
or cylindrical form, then, at the next, to an elliptical form, and so on alternately,
until the last pair of rolls is reached which gives the final form to the ingot, and
from which it passes a finished tube. Figure 144 shows the forms given the ingot
when all the balls V are cylindrical. Where these forms are used, the passes of

page_text: the rolls are alternately circular and elliptical, so that the ingot at the first pair of
rolls, indicated by the figure 1 in Figure 13, is rolled so that its exterior form
becomes elliptical, while the form of its inside wall remains round; the surplus
metal being forced away from the sides and into the parts in line with the longer
axis of the ellipse. At the next pair of rolls, indicated by 2, the ingot is again
brought to the round form, the pass in the second set of rolls being round. This
alternate rolling from ground to elliptical is continued to the last pair of rolls, which
gives the final form. Figure 14c represents mandrel halls or sections for giving the
forms to the ingots shown in Figure 14A, and Figure 14E balls or sections for giving
the form shown in Figure 14. Figure 14D represents mandrel balls or sections, all
of which are elliptical, but arranged so that the major axes of alternate balls are at
angles to each other.
In such construction, as heretofore stated, the passes of the
pairs of rolls for the balls must correspond in shape and position with the balls
placed in the passes.
The object of rolling the ingot alternately round and elliptical is to facilitate the
reduction of the ingot and its elongation into a tube.
The stock 28 of the mandrel, as represented in Figures 14B and 14F; is provided
with corrugated surfaces o, o', o" formed in any suitable way, as by cutting deep
screw threads in the stock. The purpose of this is to present to the interior
surface of the heated ingot, when passed into the stock, a series of sharp edges,
which, when the ingot is moved forward between the grips and thence to the rolls,
will scrape the inside walls of the ingot and free them of sand, scale or other
foreign substances before the rolling begins, which would have a tendency to force
such foreign substances into the walls of the tube. Another object of these
corrugations is to reduce the surface of the mandrel stock so that, when the ingot
is passed over the stocks, the cooling effects of contact with the stock shall be as
slight as possible.
At proper points, the stock is reduced to form grasping points 31 for the jaws Y Y
of the grips, which are shown on Sheet IX. These grasping points 31 may be of
any suitable shape or construction that will admit of the jaws of the grips holding
the mandrel against being turned axially. Thus, in Figure 14, the points 31 are
circular, corresponding to the shape of the jaws, but, in this case, holes 32 are
provided, into which pins 33 in the jaws enter when the grips are closed and prevent
the mandrel from rotating. In Figure 140, the said points are square in cross
section, and the jaws of the grips are correspondingly formed.
The grips represented by Figures 15, 16 and 17 consist of jaws Y, Y, pivotted to
standards X, X, secured to the bed plate in front of the first pair of rolls. These
jaws are connected with steam pistons in the cylinders Z, Z, (or other motive
power) which are arranged to receive steam (or other agent, as water, air or gas)
and by a system of valves, steam or other agent is admitted to and exhausted from
under the said pistons. The construction and operation of these grips are fully
described in the Letters Patent above referred to, and no further description of
their construction is necessary here. In their operation, the stock of the mandrel
rod T is held by the grips, and, when a tube is to be rolled, the first pair of grips D
is opened, as in Figure 16, the other pair remaining closed and holding the mandrel,
the heated ingot I is then placed on the front end of the mandrel and shoved
through the grip D to the position shown in Figure 15. Grip D is then closed
and D' opened (the mandrel being now held by grip D) the ingot shoved through
grip D' and thence fed to the first pair of rolls. Thus the heated ingot is passed
through the rolls without releasing the mandrel from the control of the grips at
any time. The valves that control the pistons that work the grips are so arranged
that it is impossible to open both grips at the same time when the machine is
working.
Eight sets or pairs of rolls are shown and referred to as used in this machine,
but a greater or less number may be used if desired.
The mandrel balls or sections must be made to correspond to the different series
of sets of rolls.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1. In a machine for rolling tubes, pipes and similar hollow articles, the com-
bination of driving gears and shafts adjusted to drive rolls of a given diameter at a
determined speed, with several series of pairs of grooved rolls, each of said series
being interchangeable with another or either of the other series, substantially as
described.
2. The combination of several series of pairs of grooved rolls, the rolls of the
corresponding pairs of the several series having the same diameter at the point of
greatest resistance and the series of pairs of rolls being interchangeable, substantially
as described.
3. The combination, in a rolling mill, of several series of pairs of grooved rolls,
the rolls of the corresponding pairs of the several series having the same diameter
on the pitch line and each series of pairs of rolls being interchangeable with the
other series, substantially as described.
4. The combination of driving gears and shafts adjusted to drive rolls of a given
diameter at a determined speed with several series of pairs of grooved rolls having
different barrel diameters and grooves of different areas but the same diameter at
the bottom of the grooves, said series of rolls being interchangeable in the same
machine to make all sizes of pipe within the scope of the machine by simply
changing the rolls.
5. A mandrel for tube rolling machines having balls or sections corresponding in
number to the pairs of rolls of which the machine is composed, the said sections
being either round in cross section or alternately round and elliptical, or all
elliptical and with the major axes of adjoining balls at right angles to each other.
Dated this 17th day of Inly 1801