IMPROVE- MENTS IN THE MANUFACTURE OF CAST-IRON PIPES AND SIMILAR ARTICLES
Year: 1861

page_text: LETTERS PATENT to David Yoolow Stewart, of Glasgow, in the County
of Lanark, North Britain,, Ironfounder, for the Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF CAST-IRON PIPES AND SIMILAR ARTICLES,
37
Sealed the 6th May 1862, and dated the 11th November, 1861.
PROVISIONAL SPECIFICATION left by the said David Yoolow Stewart at
the Office of the Commissioners of Patents, with his Petition, on the
11th November 1861.
I, DAVID YOOLOW STEWART, of Glasgow, in the County of Lanark, North
Britain, Ironfounder, do hereby declare the nature of the said Invention of
"IMPROVEMENTS IN THE MANUFACTURE OF CAST-IRON PIPES AND SIMILAR ARTICLES,
AND IN APPARATUS TO BE USED THEREIN," to be as follows, that is to say :-
This Invention comprises various improvements in the manufacture of cast-
iron pipes and similar articles, and has for object increased rapidity, and
efficiency in the formation of the outer moulds and of the cores, and in the
removal of the latter from the castings, combined with simplicity and
economy in the various details.
The Invention consists, in the first place, in ramming up the outer mould
upon a pattern constructed so that the whole or a part thereof may be con-
tracted or collapsed, to permit of its removal from the mould longitudinally
without rubbing upon the mould surface, and without opening or dividing the

page_text: mould. The collapsable pattern may be constructed according to any suitable
plan such as is at present in use in making collapsable core bars, but it is pre-
ferred to employ a metal pattern pipe or tube, which is slit longitudinally and
is provided with internal wedges or equivalent contrivances for distending or
springing it out to the required size and with a filling-up piece, which is forced
into the slit, and thus renders the cylindrical surface perfect. This pattern
contracts from its own elasticity on the withdrawal of the wedges or distending
appliances. In a similar manner the outer surface of the core may be shaped
by means of a collapsable core box, consisting of a pipe, out of which a
narrow longitudinal strip is cut, and provided with external contrivances for
compressing the pipe so as to close the slit, the core being formed in the
closed pipe. The compression is removed when the pipe springs open, and
the core can be withdrawn longitudinally with facility. In the cases of both
outer mould and core, the pattern and core box may be contrived so that their
elasticity tends to give them the shapes to be moulded instead of the reverse
as described. In ramming up the outer moulds or the cores according to
this Invention, a set of rammers, arranged in a circle, are connected by rods
of sufficient length to a frame, to which a vertical reciprocating motion is
imparted by the direct action of steam in a cylinder or cylinders to the piston
rod or rods of which the frame is connected. Provision is made for the
change of position consequent on the gradual building up of the sand, this
being done, according to one modification, by causing the steam cylinder or
cylinders to rise gradually as the ramming proceeds. It is preferred to simply
lift the rammers by the steam action, the actual ramming of the sand being
effected by their falling by their own weight. In some cases, however, their
descent may be aided by the steam action. According to the present Inven-
tion the cores are dried in their places in the outer moulds and along with the
latter, whereby a considerable saving in stove space and in fuel is obtained.
In practising the part of the Invention relating to the removing of the
cores from the castings, according to one modification, a rotating tool, such as
a cylindrical saw or a tube furnished with cutting or abrading instruments is
made to enter the pipe at one end, and by its rotation to cut or break away
more or less of the sand between the inside surface of the pipe and the
central bar of the core. As the action proceeds the clearing-out tool is made
to move along, and on completing its traverse will have made the core bar
quite loose and free from the casting, so that it can be removed with the
greatest facility. In making up the core with a view to its being removed in
this
way, it is unnecessary to use an expensive callapsable core bar, as a simple
rigid one, either solid or hollow, may be used, and in using such rigid bar it is

page_text: not necessary to apply the usual coating of straw beneath the sand. The
sand portion of the core may, however, in some cases be formed with longi-
tudinal cavities, to serve the triple purpose of allowing the air or gases to
escape, of providing for the compression of the sand by the contraction of
the casting, and of forming outlets for the sand in the subsequent operation of
cutting it away, when this is effected from above. These cavities may be on
the surface of the core bar, or partly in it and partly in the sand. If the
clearing-out tool is to be applied from below, it is shaped so that the sand
can fall clear away as it is cut; the application, however, of a clearing-out
tool is not confined to any particular positions of the casting, and various kinds
of tools may be used according to circumstances; thus, in some cases, a
reciprocating tool working longitudinally may be applied, being introduced at
one of the cavities referred to, and being gradually moved round the inside
of the casting. Or, according to a further modification, the cavities in the
sand may be arranged so as to leave between them barely sufficient material
for the support and strength of the core surface, and on proceeding to clear
the casting a longitudinal or torsional strain may be applied to the core bar
by an hydraulic press or other adequate means, which will have the effect of
breaking through the sand between the cavities, and thereby loosen and free
the core bar.
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 10th May 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
YOOLOW STEWART, of Glasgow, in the County of Lanark, North Britain, Iron-
founder, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of November, in the year of our Lord
One thousand eight hundred and sixty-one, in the twenty-fifth 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

page_text: and Ireland, the Channel Islands, and Isle of Man, an Invention for "IM-
PROVEMENTS IN THE MANUFACTURE OF CAST-IRON PIPES AND SIMILAR ARTICLES,
AND IN APPARATUS TO BE USED THEREIN," upon the condition, amongst others,
that I, the said David Yoolow Stewart, my executors or administrators, by
ân instrument in writing undèr 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 performed, to be particularly described and ascertained in and by the
following statement in writing, reference being had to the accompanying
Drawings, and to the letters and figures marked thereon, that is to say :--
My said Invention comprises various improvenients in the manufacture of
cast-iron pipes and similar articles, and in apparatus to be used therein, and
has for object increased rapidity and efficiency in the formation of the outer
moulds and of the cores, and in the removal of the latter from the castings,
combined with simplicity and economy in the various details.
And in order that my said Invention may be properly understood and
carried into effect, I have hereunto appended a Sheet of explanatory Draw-
ings, illustrating such parts, as appear to me to require it, of the following
particular description of my improvements.
The Invention consists, in the first place, in ramming up the outer mould
for a pipe or similar article upon a pattern constructed, so that the whole or a
part thereof may be contracted or collapsed to permit of its removal from the
mould longitudinally without rubbing injuriously upon the mould surface, and
without its being required to open or divide the mould. The collapsable
pattern may be constructed according to any suitable plan, such as is at
present in use in making collapsable core bars; but it is preferred to employ
a metal pattern pipe or tube, such as is shown at A, in Figure 1, on the
accompanying Sheet of Drawings. This Figure represents the metal pattern
pipe A, as having been just lowered from the mould 'box B, down upon a
carriage C in a trench D, running transversely under a failway E, upon
which is the carriage F carrying the mould box B. Figure 2 is an enlarged
transverse section, through the mould box B, sand b, and pattern 'A, the last
being supposed to be still in the mould. The pattern A is slit longitudinally,
the slit or opening being slightly tapered to receive a longitudinal wedge G,
whilst the faucet end of the pattern is h ld firmly by a malleable iron ring H

page_text: shaped externally to the desired contour. The wedge G and the corresponding
edges of the slit are shaped angularly, as shown in Figure 2, so as to retain
the wedge accurately in position. The sand is rammed upon the pattern when
the latter is in its distended condition, and the wedge G is then withdrawn,
whereupon the elasticity of the pattern causes it to contract, and so free itself
from the mould. It is then lowered out of the mould down upon the
carriage C below, and the mould box with the outer mould formed within it
is moved away on its carriage F. In a similar manner the outer surface of
the core may be shaped by means of a collapsable core box, consisting, for
example, of a pipe or tube I, Figure 3, out of which a narrow longitudinal
strip is cut. This core box may be conveniently fitted up in a frame J,
situated over a trench K, having a railway along its bottom for the carriages L
carrying the core bars M. The core bar M (which may be either a simple
rigid one, as shown, or a collapsable one) being brought on its carriage L
under the core box I is raised up into the latter, and the core box being fixed
in its closed or contracted condition sand is rammed in to form the core
surface. The parts of the core box being afterwards allowed to expand free
themselves from the core, which is then lowered upon its carriage L, and con-
veyed away to a part where the mould box (B, Figure 1, for example), can
be placed over it, and the core be lifted directly up into its place in the mould.
In the cases of both outer mould and core, the pattern and core box may be
contrived, so that their elasticity tends to give them the shapes to be moulded
instead of the reverse, as described. Thus, the core box, as shown in cross
section in Figure 11, may be made, so that it tends to take the contracted
shape necessary to form the core. A slit is formed in it longitudinally, and is
occupied by a wedge g, having a slight longitudinal taper. After the core is
rammed up this wedge is driven further in, and it causes the core box to
expand, so that the core may be withdrawn from it. To keep the core box
closed whilst being rammed, flanges 9 are, if necessary, formed on it near
each edge of the slit, and are connected by screw bolts 10. In ramming up the
outer moulds or the cores, according to this Invention, direct-acting steam ram-
ming apparatus is used, such as is shown in elevation in Figure 4, and in sectional
plan in Figure 5. In this modification of the apparatus a set of rammers N
arranged in a circle are connected or attached to a frame or disc P, to which
a vertical reciprocating motion is imparted by the direct action of steam in a
cylinder Q to the piston rod R, of which the frame or disc P is connected or
attached. The steam cylinder Q is shown in vertical section in Figure 6, the
section being taken through the valve chamber S, and valve s. The exhaust
port is to one side, and the-bottom of the cylinder is put in communication

page_text: with it by the upward movement of the valve s. The valve rod T has two
adjustable studs t, t', upon it, between which there plays the forked end of an
arm U, fixed upon the piston rod R. The steam being admitted under the
piston lifts it until the arm U coming into contact with the upper stop t shifts
the valves, and the steam then escaping the piston falls, and with it the disc P,
and the rammers N. Provision is made for the change of position consequent
on the gradual building-up of the sand, this being done according to one modifi-
cation, by causing the steam cylinder Q to rise gradually as the ramming
proceeds. For this purpose the cylinder is formed with grooved flanges. q,
fitted to slide upon vertical guide bars V; and the cylinder is suspended by
chains w passing over pulleys W, to counterweights, which are made slightly
in excess of the cylinder. As the sand gets gradually built up the rammers
descend gradually less far, and the counterweights always raise up the cylinder
until it begins to bear up the weight of the piston, piston rod, disc, and
Steam is admitted to the cylinder by means of flexible, jointed, or
telescopic tubing permitting of its change of position. It is preferred to
simply lift the rammers by the steam action, the actual ramming of the sand
being effected by the fall due to their own weight; in some cases, however,
their descent may be aided by the steam action. Two or more steam cylinders
may in some cases be used instead of one. It is necessary to turn the ram-
mers N into a new position between each stroke, and for this purpose a series
of ratchet teeth are formed round the frame or disc P, and as the disc is
elevated it comes in contact with a pawl ✗, centred on a stationary stud upon
the cylinder Q, and the action of this pawl on the ratchet teeth is such as to
make the disc turn the necessary distance. The disc P is formed with radial
slots to permit of the adjustment of the rammers N to suit different diameters.
According to the present Invention the cores are dried in their places in the
outer moulds, and along with the latter, whereby a considerable saving in stove
space and fuel is obtained.
rammers.
In practising the part of the Invention relating to the removing of the cores
from the castings, according to one modification, a rotating tool, such as a
cylindrical saw, or a tube furnished with cutting or abrading instruments is
made to enter at one end between the pipe and the core bar, and by its
rotation to cut or break away the sand, or a part of it, between the inside
surface of the pipe and the central bar of the core. As the action proceeds the
clearing-out tool is made to move along, and on completing its traverse will
have made the core bar quite loose, and free from the casting, so that it can
be removed with the greatest facility. In making up a core with a view to its
being used in this way it is not necessary to use an expensive collapsable core

page_text: bar, as a simple rigid one, either solid or hollow, may be employed; and in
using such rigid bar it is not necessary to apply the usual coating of straw
beneath the sand. The sand portion of the core may, however, in some cases
be formed with longitudinal cavities, as shown in cross section in Figure 7, to
serve the triple purpose of allowing the air or gases to escape, of providing for
the compression of the sand by the contraction of the casting, and of forming
outlets for the sand in the subsequent operation of cutting it away when this is
effected from above. These cavities may be on the surface of the core bar Y,
or partly in it and partly in the sand, or entirely in the sand a.
If the clearing
or cutting-out tool is to be applied from below it is shaped so that the sand can
fall clear away as it is cut; the application, however, of a clearing-out tool is
not confined to any particular positions of the casting, and various kinds of
tools may be used according to circumstances. Thus, in many cases, I prefer to
use a reciprocating tool working longitudinally, such as a saw, which is intro-
duced through a longitudinal cavity formed by embedding in the sand of the
core, and then withdrawing therefrom a lath or rod Z, as shown in Figure 3.
Figure 8 is a longitudinal section of a newly cast pipe, showing the applica-
tion to it of the cutting-out saw. On the central rod 1 of the core bar Y,
there is fitted loosely between collars a boss 2, formed with a horizontal arm 3,
which is provided with an adjustable guide for the saw 4. The saw is con-
nected by a link to a lever 5, centred upon another arm 6, formed on the
boss 2. The saw blade 4 being entered through the cavity in the sand of the
core, a weight 7 is hung to the bottom of it, and the necessary reciprocating
motion is imparted to it by means of the lever 5, the parts being turned
gradually round upon the centre rod 1, as the sawing proceeds.
Figure 9 is a cross section corresponding to Figure 8, and Figure 10 is a
plan of the bottom plate of the core bar, which plate is formed with a slot 8,
extending round slightly more than a semicircle for the saw to work through,
and for the escape of the sand. It is not necessary to saw further round than
this slot will permit, as when that extent is sawn, the core can be easily
separated on the opposite side, and so be removed from the casting.
According to another modification, the cavities in the sand may be arranged
or proportioned so as to leave between them barely sufficient material for the
support and strength of the core surface, and on proceeding to clear the casting
a longitudinal or torsional strain may be applied to the core bar by a hydraulic
press or other adequate means, which will have the effect of breaking through
the sand between the cavities, and thereby loosen and free the core bar.
It will be understood by the practical ironfounder, that some well-known
minor details and processes concerned in the manufacture of cast-iron pipes

page_text: and similar articles have not been referred to in the preceding description, as
the present Invention does not relate.to them.
In the accompanying explanatory Drawings the arrangements have been
represented as for casting pipes with their faucets downwards; but the Inven-
tion is for the most part equally applicable in the case of casting with the faucets
uppermost, a few obvious modifications of minor details being alone required.
Various other details may also be modified; thus, for example, instead of
raising and lowering the patterns and core bars, as described, the mould boxes
and core boxes may be lowered upon and raised from the patterns and
core bars.
Having thus particularly described my said Invention and the manner in
which the same is or may be performed, I have to state that I do not restrict
myself to the precise details herein described or delineated, but that what I
consider to be novel and original and claim as the Invention secured to me by
the herein-before in part recited Letters Patent is,-
1. Generally, the forming of the outer moulds and cores for pipes and similar
articles, and the removing of the cores, substantially in the manner herein-
before described, and more particularly,
2. The employing of a collapsable pattern in shaping the outer mould.
3. The employing of an elastic collapsable or expanding core box in shaping
the cores.
4. The actuating of the rammers by means of a direct-acting steam cylinder.
5. The drying of the cores and moulds together, that is with the cores in
their places in the latter.
6. The freeing of the core bar from the casting by means of a revolving or
reciprocating tool partially cutting away the sand.
In witness whereof, 'I, the said David Yoolow Stewart, have hereunto
set my hand and seal, this Eighth day of May, in the year of our
Lord One thousand eight hundred and sixty-two.
DIV
7
DAV. Y. STEY
TITAN XXY ADT
RT. (..)