IMPROVEMENTS IN 'CORE-BARS USED IN THE CASTING OF METAL RAIN-WATER, HOT AND COLD WATER, GAS AND SOIL, PIPES AND OTHER HOLLOW CASTINGS OF SIMILAR KIND
Year: 1878

page_text: PROVISIONAL-SPECIFICATION_left_by_Joseph
Crosthwaite at the Office of
the Commissioners of Patents on the 11th December 1878.
JOSEPH CROSTHWAITE, of Bo'ness, in the County of Linlithgow, Scotland,
Managing Partner of the Forth Bank Foundry Company. "IMPROVEMENTS IN
'CORE-BARS USED IN THE CASTING OF METAL RAIN-WATER, HOT AND COLD
WATER, GAS AND SOIL, PIPES AND OTHER HOLLOW CASTINGS OF SIMILAR KIND."
This Invention relates to certain improvements in "core-bars" used in the
casting of metal pipes such as are used for rain-water, hot and cold water, gas and
soil conducting pipes or for heating pipes, and such core-bars are also applicable in
the manufacture of other hollow castings of a similar kind, such as columns and
such like wherein the metal forming the casting is to be hollow, and of even thick-
ness throughout. The object is by employing a rigid core-bar, and one that will
carry or "hang" the core the core sand instead of the flexible core-bars hitherto used to
simplify and improve the manufacture of the said kind of castings, and consists in
making or forming the said core-bars so as to prevent the bending of the "core
whilst the molten metal is being poured into the mould, and thereby obviate or
prevent any variation in the thickness of the casting produced.
"
The formation of the core-bar, which I prefer, for purpose of simplicity and
strength combined, is to be as a feathered or footed beam of substantially shape,
flat or semicircular at the bottom or underside of the sole or feather, so as to
provide a rigid bar that will carry the core sand, but the core-bar may be made
circular, semicircular, triangular, or of any other section, and hollow, and in these
cases strengthened by internal webs for purpose of ensuring in such core-bars the
requisite rigidity. These said internal stengthening webs being of H, Y, X, cross
or other section suitable for the purpose.
The core-bar of the feather and beam form or any other section of bar will be
provided with longitudinal perforations or cavities, one or more, and with transverse
or radial side holes or inlets communicating with the said longitudinal cavities for
the purpose of carrying off the gases in casting, whereby "pricking" will be
rendered unnecessary, but the improved core-bars may be made without this
provision.
These core-bars. of whatever section will in some cases be corrugated, fluted,
studded, or otherwise roughened on their outer faces to hold or "hang
the sand

page_text: which forms with the sand bar the core or interior mould of the casting, the object
in all cases being to ensure the rigidity of the "core," and so to dispense with the
employment of " chaplets," "nails," or "pin and saddle," as at present variously
used to keep the core from rising in the centre when pipes and such like articles are
being cast, and by so doing the castings can be made free from flaw or blemish and
true to thickness, throughout, and all the risk of loss and time expended in ad-
justing "chaplets," "nails," or "pins," is obviated and saved.