IMPROVEMENTS IN CORE BARS AND STUDS TO BE USED FOR CASTING IRON PIPES AND SIMILAR ARTICLES
Year: 1867

page_text: Sealed the 17th September 1867, and dated the 21st March 1867.
PROVISIONAL SPECIFICATION left by the said David Yoolow Stewart
at the Office of the Commissioners of Patents, with his Petition, on the
21st March 1867.
I, DAVID YOOLOW STEWART, of Glasgow, in the County of Lanark, North
Britain, Ironfounder, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN CORE BARS AND STUDS TO BE USED FOR CASTING IRON PIPES
AND SIMILAR ARTICLES," to be as follows, that is to say :-
This Invention relates to core bars and studs to be used for casting iron
pipes and similar articles, and the improvements in core bars comprise the
following features of novelty, namely, first, making the core bar to consist of
a cylinder divided or slit longitudinally in two or more places from one end
nearly to the other end, the divisions or slits being either parallel to the axis
or more or less inclined or helical; secondly, making the slit or divided
cylinder with some slits from one end and some from the other; and, thirdly,
[Price 8d.]

page_text: making the cylinder with one division or slit completely through from end to
end combined with other slits, each extending from one end not quite to the
other end. The cylinder or core bar is distended by wedges or otherwise,
and is covered with sand or mould material, and after the pipe or other article
is cast upon it the parts are allowed to collapse to facilitate the removal of
the core bar from the casting.
In practically carrying out this part of the Invention the segments or
partially separated parts forming the core bar may be made in one piece or
casting, remaining united at one end, or they may be distinct pieces fixed on a
ring or on segments of rings. When made without cutting the casting completely
through the connection between the segmental parts, and the undivided ring or
end part is reduced by cross cutting or otherwise to allow of the slight bending
at the connections which takes place when distending the segments.
The improvements in studs consist in combining and using certain parts in
the following manner:-When casting pipes or similar articles in a hori-
zontal position, or whenever the relative positions of parts of the mould require
to be accurately gauged, the parts are a thickness stud, which remains
in the thickness of the metal, a supporting stud, and an intermediate
part. The thickness stud is made by preference of malleable or malleable
cast iron, and is turned by preference of larger diameter at the ends than at
the middle, and with a small conical part at the end corresponding to the
outside of the pipe, whilst a small hole is drilled into the other end or a small
pin is left projecting thereon. The supporting stud is a metal bar which is
forced into the core through a hole made for the purpose in the core box, and
whilst resting on the core bar has its outer end flush with the surface of the
core. A small hole is drilled in the outer end of the supporting stud to
receive the pin of the thickness stud or the intermediate piece, which is a
small pin or peg of wood or other material, either alone or in combination
with a small washer of leather or other combustible material. The thickness
stud is kept in its proper position by means of the projecting pin on the
thickness stud, or the pin or peg and washer between the thickness and
supporting studs, so that when the mould is closed the conical point of the
thickness stud penetrates the mould material and meets a metallic surface
provided in the flask or mould box, and by these means the parts have their
distances apart rigidly gauged, so that no disturbance can take place whilst
the operation of casting is effected. The intermediate pin or peg (if of wood)
and the washer are burnt away by the heat of the casting, thus offering no
impediment to the contraction of the metal. The conical point of the thickness
stud may be afterwards hammered down so as to rivet the stud tightly in its

page_text: place, and any projecting part is finally filed off if required. Two or more
studs may be used in one mould and at whatever parts thereof they may be
found useful.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said David Yoolow Stewart in the Great Seal Patent Office on
the 20th September 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
YOOLOW STEWART, of Glasgow, in the County of Lanark, North Britain,
Ironfounder, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of March, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirtieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said David Yoolow Stewart, Her special licence that I, the said David
Yoolow Stewart, my executors, administrators, and assigns, or such others
as I, the said David Yoolow Stewart, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United Kingdom
of Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN CORE BARS AND STUDS TO BE USED FOR CASTING
IRON PIPES AND SIMILAR ARTICLES," upon the condition (amongst others)
that I, the said David Yoolow Stewart, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands
and seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and cause the
same to be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said David Yoolow Stewart, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement in writing, reference being had to the accompanying Drawings, that
is to say:
My said Invention relates to core bars and studs to be used for casting iron
pipes and similar articles; and in order that the Invention and the manner of
performing the same may be properly understood, I have hereunto appended a

page_text: Sheet of explanatory Drawings to be herein-after referred to, and representing
examples of my improved arrangements.
My improvements in core bars comprise the following features of novelty,
namely, first, making the core bar to consist of a cylinder divided or slit longi-
tudinally in two or more places from one end nearly to the other end, the
divisions or slits being either parallel to the axis or more or less inclined or
helical; secondly, making the slit or divided cylinder with some slits from one
end and some from the other; and, thirdly, making the cylinder with one
division or slit completely through from end to end combined with other slits,
each extending from one end not quite to the other end. The cylinder or core
bar is distended by wedges or otherwise, and is covered with sand or mould
material, and after the pipe or other article is cast upon it the parts are
allowed to collapse to facilitate the removal of the core bar from the casting.
In practically carrying out this part of the Invention the segments or
partially separated parts forming the core bar may be made in one piece or
casting remaining united at one end or at both ends, or they may be distinct
pieces fixed on a ring or on segments of rings. When made without cutting
the casting completely through the connection between the segmental parts
and the undivided ring or end part is reduced by cross cutting or otherwise to
allow of the slight bending at the connections, which takes place when
distending the segments.
Figure 1 on the accompanying Sheet of Drawings is a cross section of a
core bar, as made according to one modification of my improvements; Figure 2
is a side elevation, Figure 3 is a longitudinal section, and Figure 4 is another
cross section.
The shell of this core bar is made with four longitudinal slits, which divide
it into four segments 1, 2, 3, 4, but which are united together at the ends.
Bushes 5, 6, are fixed in the ends, and are bored to receive a central spindle 7,
one end of which is squared to receive a handle for turning it by; on this
spindle there are fixed three bosses 8, 9, 10, formed with grooves, the
bottoms of which are spiral or inclined. Pins 11 are screwed into the segments
so as to enter the grooves of the bosses 8, 9, 10, and when the spindle 7 is
turned these bosses act on the pins 11 in such a way as to force out the seg-
ments. When the spindle 7 is turned the other way the segments collapse
from their own elasticity. When the core bar is of considerable length, as
compared with its diameter, the segments may tend to spring out too far at
the middle of their length; in such cases, however, their movement is limited
or controlled by one or more bosses, such as the one 12, which is loose
on the spindle, and which has pins 13 screwed into it through holes in the

page_text: segments; these holes are countersunk, and the pins are formed with heads,
which limit the outward movement of the segments without preventing their
collapsing. Both ends of the core bar are made slightly tapering, but one
end of the core bar is made slightly less than the other, namely, the end that
has to be drawn through the cast pipe when removing the core, but the full
diameter of the core is made up by the covering of sand or mould material being
made slightly thicker at that part. Strips of thin metal may be applied to
cover the slits between the segments to prevent sand from entering thereat,
each strip being fixed by one edge to one of the segments.
The improvements in studs consist in combining and using certain parts in
the following manner:-When casting pipes or similar articles in a horizontal
position, or whenever the relative positions of parts of the moulds require to be
accurately gauged. Figure 5 is a cross section of a core box with a core being
formed in it, and Figure 6 is a cross section of a mould box, showing the pipe
as already cast in it. The parts are a thickness stud a, which remains in the
thickness of the metal b, a supporting stud c, and an intermediate part. The
thickness stud is made by preference of malleable or malleable cast iron, and is
turned by preference of larger diameter at the ends than at the middle, and
with a small conical point at the end corresponding to the outside of the pipe,
whilst a small hole is drilled into the other end, or a small pin is left projecting
thereon. The supporting stud c is a metal bar, which is forced into the core
through a hole made for the purpose in the core box d, and whilst resting on
the core bar has its outer end flush with the surface of the core. A small
hole is drilled in the outer end of the supporting stud to receive the pin of
the thickness stud or the intermediate piece, which is a small pin or peg of
wood or other material, either alone or in combination with a small washer of
leather, or other combustible material. The thickness stud a is kept in its
proper position by means of the projecting pin on the thickness stud, or the
pin or peg and washer between the thickness and supporting studs a, c, so
that when the mould is closed the conical point of the thickness stud a pene-
trates the mould material and meets a metallic surface e provided in the flask
or mould box; and by these means the parts have their distances apart rigidly
gauged, so that no disturbance can take place whilst the operation of casting is
effected. The intermediate pin or peg (if of wood) and the washer are burnt away
by the heat of the casting, thus offering no impediment to the contraction of the
metal. The conical point of the thickness stud may be afterwards hammered
down so as to rivet the stud tightly in its place, and any projecting part is
finally filed off, if required. Two or more studs may be used in one mould
and at whatever parts thereof at which they may be found useful.

page_text: Having thus particularly described my said Invention, and the manner in
which the same is to be performed, I have to state that what I believe to be
novel and original, and claim as the Invention secured to me by the herein-
before in part recited Letters Patent is,-
1. The making of core bars to be used for casting iron pipes and similar
articles in the improved modes herein-before described.
And, 2. The combining and using of a thickness stud, a supporting stud,
and an intermediate part in the improved manner herein-before described.
In witness whereof, I, the said David Yoolow Stewart, have' hereunto
set my hand and seal, this Eighteenth day of September, in the year
of our Lord One thousand eight hundred and sixty-seven.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
DAV. Y. STEWART. (L.S.)