Improvements in Mandrels for Tube Rolling Machines.
Year: 1890

page_text: Date of Application, 24th May, 1890
Complete Specification Left, 20th Feb., 1891-Accepted, 28th Mar., 1891
PROVISIONAL SPECIFICATION.
Improvements in Mandrels for Tube Rolling Machines.
A communication from abroad by CHARLES KELLOGG, of Findlay, in the County
of Hancock and State of Ohio, 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 construction of mandrels for pipe and tube rolling
machines of that class for which Letters Patent were granted to my correspondent,
dated February 19, 1889, No. 2933.
The present invention relates to improvements in the construction of mandrels for
the said machines and others resembling it in operation or producing equivalent
results, and the object of the invention is first to provide a mandrel which can be
easily and cheaply constructed and in which the bearing surfaces can be readily
changed to suit the different sizes of pipe, etcetera, which it is desired to make;
secondly, to provide bearing surfaces to resist the exterior pressure of the several
pairs of rolls, which shall extend for some distance on either side of the nip of the
rolls; thirdly to construct the said interior supporting or bearing surfaces so that
they shall be of such shape in cross section that the ingot while being rolled may
be made to assume various forms in cross section as for example from round to
elliptical alternately, or successively elliptical but with the longer axes of the
ellipses formed by adjacent pairs of rolls at right or other practicable angles to
each other, in order that the reduction and elongation of the ingot may be
facilitated, lastly to provide the mandrel with means for clearing the interior of
the ingot pile or bloom from sand or other foreign substances.
The
The stock or tang of the mandrel is provided with corrugated surfaces formed
in any suitable way as for example by cutting screw threads on the surface.
object in thus forming the mandrel stock is to present to the interior surface of the
ingot when passed over the rear end of the mandrel a series of sharp annular edges,
which, when the ingot is moved forward between the grips and thence to the rolls,
scrape the interior surface of the ingot and thereby free it from sand, scale and
other foreign substances before the rolling begins. Another object is to reduce the
surface of the mandrel stock so that when the ingot is passing from the stock to
the grips and thence to the rolls the cooling effects of the contact of the ingot with
the stock shall be as slight as possible. At proper points the stock or tang is
reduced to form grasping points for the jaws of the grips, which are fully shown
and described in the Specification of the Letters Patent above referred to. These
grasping points may be of any suitable shape or construction that will admit of the
grips holding the mandrel firmly against being turned axially. The mandrel rod
is preferably formed of steel rod sections of different sizes screwed end to end into
a splicing block and with the rear end of the larger section screwed into the stock
of the mandrel. On this mandrel rod are placed the bearing surfaces for supporting
the interior walls of the ingot while being rolled. Preferably these bearing surfaces
consist of blocks or balls. These balls are perforated longitudinally so as to be
placed on the mandrel rod where they are held and spaced by sections of tubing,
the last ball of the series being held by a jam nut screwed onto the extremity of
the mandrel rod. But where the mandrel rod is composed of sections, at the end
of each section except the last is a block which serves to hold the balls of the
ections on the section of rod at the end of which it is placed.

page_text: The balls correspond in position to the successive pairs of rolls in the machine-
the mandrel being adjusted so that a ball will be located in the pass of each pair of
rolls, furthermore the area of the said balls in cross section decreases corre-
spondingly to the decreasing area of tlie passes of the successive pairs of rolls. The
general form of the balls in cross section may be cylindrical or alternately elliptical
and cylindrical, or all except the last ball which gives the desired form to the pipe
may be elliptical. Where successive elliptical balls are used it is preferred that
they shall be arranged on the mandrel rod so that the longer axis of one ball shall
be at an angle (say a right angle) to the longer axes of the balls on either side of
it. When so arranged the passes of the respective rolls may correspond to the
form of the balls placed in them if desired.
In the operation of a machine provided with a mandrel having balls of the form
and arrangement last described, the ingot is caused to assume an elliptical form in
cross section while being rolled, but at each pass and with every reduction the axes
of the ellipse are changed, and the walls of the ingot are alternately expanded and
compressed in different directions, the extent of this expansion and compression,
however, being less at every pass until finally at the last pair of rolls but one the
walls are reduced to the desired thickness and the last pair of rolls serves merely to
bring the tube to the shape required and finish it.
The balls are preferably cylindrical or cylindroidal, that is their longitudinal
surface is considerably greater than their diameter, so that they afford a bearing
for the ingot on both sides of the passes of the rolls. The term cylindrical, it
must be understood, is applied to the balls which are round in cross section and the
term cylindroidal to those which are elliptical. The balls may be made of any
suitable material, but it is preferred that they be made of cast iron.
Dated this 23rd day of May 1890.
WM. P. THOMPSON & Co.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Mandrels for Tube Rolling Machines.
A communication from abroad by CHARLES KELLOGG, of Findlay, in the County
of Hancock and State of Ohio, 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 construction of mandrels for pipe and tube rolling
machines of that class for which Letters Patent No. 2933 were granted as a com-
munication to me, dated February 12, 1889.
The machine shown and described in the Specification of said Patent consists of a
series of pairs of rolls provided with grooves of gradually decreasing area, by
means of which an ingot pile or bloom is gradually reduced and elongated into a
hollow cylinder of the desired size and shape in cross section; and in connection
with the said grooved rolls, a tapering mandrel is used, which is placed in the
grooves between each pair of rolls and extends the whole length of the machine, so
as to form a support for the interior of the ingot while undergoing reduction and
elongation; the said mandrel being held and centered between the rolls by means
of a system of grips contrived to admit of one being released while the other con-
tinues to hold the mandrel and thereby the heated ingots can be passed on to the
mandrel and thence to the rolls without stopping or displacing the mandrel.
The present invention relates to improvements in the construction of mandrels

page_text: for the said machines and others resembling it in operation or producing equivalent
results, and the object of the invention is first to provide a mandrel which can be
easily and cheaply constructed and in which the bearing surface can be readily
changed to suit the different sizes of pipe, etcetera, which it is desired to make;
secondly, to provide bearing surfaces to resist the exterior pressure of the several
pairs of rolls, which shall extend for some distance on either side of the nip of the
rolls; thirdly, to construct the said interior supporting or bearing surfaces so that
they shall be of such shape in cross section that the ingot, while being rolled, may
be made to assume various forms in cross section, as for example, from round to
elliptical alternately, or successively elliptical, but with the longer axes of the
ellipses formed by adjacent pairs of rolls at right or other practicable angles to
each other, in order that the reduction and elongation of the ingot may be
facilitated; lastly, to provide the mandrel with means for clearing the interior of
the ingot pile or bloom from sand or other foreign substances.
In the accompanying drawing :-
Figure 1 represents a sectional side elevation of the improved mandrel.
Figure 2 cross sections of the same on line 1 1, 2 2, 3 3, 4 4, 5 5, 6 6, when the
bearing surfaces are cylindrical.
Figure 3 represents one of the grips with a section of the mandrel taken on
line xx.
Referring to the drawings
:-
The stock or tang A of the mandrel is provided with corrugated surfaces a a a,
formed in any suitable way, as for example, by cutting screw threads on the surface.
The object in thus forming the mandrel stock is to present, to the interior surface
of the ingot when passed on to the rear end of the mandrel, a series of sharp
annular edges, which, when the ingot is passed forward between the grips and
thence to the rolls, will scrape the interior surface of the ingot and thereby free it
from sand, scale and other foreign substances before the rolling begins. Another
object is to reduce the surface of the mandrel stock so that, when the ingot is
passing from the stock to the grips and thence to the rolls, the cooling effect of the
contact of the ingot with the stock shall be as slight as possible. At proper points,
the stock or tang A is reduced to form grasping points b b for the jaws of the grips,
which are not shown, but the construction and operation of which are fully shown
and described in the Letters Patent above referred to. These grasping points may
be of any suitable shape or construction that will admit of the grips holding the
mandrels firmly against being turned axially. Thus, in Figure 1, the points bb
are shown to be circular, corresponding to the shape of the jaws of the grips, but,
in this case, holes should be provided, into which pins in the jaws of the grips may
enter when the grips are closed, and hold the mandrel firm. But the grasping
points bb may be squared and the jaws of the grips correspondingly formed. The
mandrel rod is preferably formed of steel rod sections e e' of different sizes screwed
end to end into a block D and the rear end of the larger section e screwed into the
stock or tang A of the mandrel. On this mandrel rod, are placed the bearing
surfaces for supporting the interior walls of the ingot while being rolled. Preferably,
these bearing surfaces consists of blocks or balls E to E8 (8 or more being used in
practice, but those between 4 and 8 being omitted from the drawing).
These balls are perforated longitudinally so as to be placed on the mandrel rod,
where they are held and spaced by sections of tubing f, the last ball of the series
being held by the jam nut screwed on to the extremity of the mandrel rod. But
where the mandrel rod is composed of sections, as in Figure 1, at the end of each
section except the last is a block D, which serves to hold the balls of the sections
on the section of rod at the end of which it is placed. The balls, E, etcetera, cor-
respond in position to the successive pairs of rolls in the machine, the mandrel being
adjusted so that a ball will be located in the pass of each pair of rolls. Further-
more, the area of the said balls in cross section decreases correspondingly to the
decreasing area of the passes of the successive pairs of rolls. The general form of
the balls in cross section may be cylindrical, as represented in Figure 2, or

page_text: alternately elliptical and cylindrical, or all except the last ball (E³), which gives the
desired form to the pipe, may be elliptical. Where successive elliptical balls are
used, it is preferred that they shall be arranged on the mandrel rod so that the
Jonger axis of one ball shall be at an angle (say a right angle) to the longer axes of
the balls on either side of it. When so arranged, the passes of the respective rolls
should correspond to the form of the balls placed in them. The sides or surface of
the mandrel balls are parallel to the mandrel rod, and, as they are considerably
longer than the passes in the rolls, it is plain that they can be shifted lengthwise
without changing the space between them and the nip of the rolls; whereby, in case
of becoming worn, they can be moved so as to present an unworn surface to the nip
of the rolls. This construction also does away with such nicety of adjustment
as is necessary when the balls are elliptical in longitudinal section, or tapering.
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 1 claim is :-
1. In mandrels for machines for rolling pipe, etcetera, the combination, with a
mandrel rod, of a series of cylindrical or cylindroidal balls of gradually decreasing
area in cross section_strung on a mandrel rod and spaced and held thereon, sub-
stantially as specified.
2. In a mandrel, a mandrel rod, a series of cylindrical or cylindroidal balls of
gradually decreasing area in cross section, and the corrugated surface on the tang
of the mandrel, substantially as specified.
Dated this 18th day of February 1891,
WM. P. THOMPSON & Co.,
Agents for the Applicant.