Improvements in the Production of Hollow Steel Ingots and in Apparatus therefor.
Year: 1891

page_text: Date of Application, 25th Nov., 1891
Complete Specification Left, 25th Aug., 1892-Accepted, 1st Oct., 1892
Improvements in the Production of Hollow Steel Ingots and in
Apparatus therefor.
I EDWARD KENWORTHY DUTTON of the firm of Dutton & Fulton of No. I
St. James Square, Manchester, in the County of Lancaster, Consulting Engineers
and Fellows of the Institute of Patent Agents do hereby declare the nature of this
invention (communicated to me from abroad by Albert Mathies of 23 Hallerstrasse
Hamburg in the Empire of Germany Manager) to be as follows:-
My invention relates to the production of hollow steel ingots for use in the
manufacture of hollow shafts tubes and other tubular bodies as is now well under-
stood. In the casting of such ingots cores have been inserted within the mould as
is usual when casting hollow bodies but difficulties have been experienced in
providing cores which would meet all the requirements. It is necessary that
such cores shall be firm enough to withstand the pressure of the metal and shall at
the same time be capable of yielding as the metal contracts or of being withdrawn
before the contraction commences or has proceeded to any great extent.
I employ cores which can be readily withdrawn and which in some cases can be
expanded before withdrawal so as to exert a pressure upon the setting metal. One
form of core consists of a sheet of thin sheet iron or mild steel coiled into a
cylindrical form the sheet used being of a length amounting to two or more times
the circumference of the required core.
By thus coiling up a long thin sheet I am enabled to obtain sufficient strength in
the core at the same time that the core can be readily removed from the ingot.
The removal would be effected by stripping off the sheet after the ingot had set
to a suitable degree or if preferred after the ingot had been removed from the
mould. To facilitate the removal from the ingot I propose to attach the inner end
of the coil to an inner shaft or tube which can be rotated at the required time so as
to coil up the sheet metal and to thereby strip it from the ingot or otherwise to
form it into a coil of reduced diameter so that it can be lifted out of the ingot. In
place of the coiled core I may use a sectional core provided with a tapering square
or polygonal central expanding block. The sections may be connected with the
central block temporarily or permanently by means of dovetail keys or may have
plain faces to meet the faces on the said block. The joints between the sections
may be provided with curved covering plates. The ingot may be cast with the core
in its contracted form and the expanding block be afterwards forced downward or
inward so as to expand the core thereby compressing the soft metal or the metal
may be run with the expanding block in position and the block be withdrawn after
a suitable interval. After such withdrawal the core would be free to contract and
the sections could be lifted out.
In the cases wherein the sections would be attached to the block they would be
removed with such block the first withdrawing movement of the block having the
effect of contracting the core so as to render it capable of being lifted out along
with the block. I may remove the central block prior to the running and fill or
partly fill the spaces with sand or with wood or with a substance or material which
would furnish a support until the metal had set and would by failing or by becoming
melted or burnt permit the sections to contract. I may use water or fluid to
prevent overheating of the core but I do not claim such use as novel apart from the
novel construction and use of the core. For the same purpose I may force air in

page_text: at the lower end of the core and permit it to escape upward through the spaces or
I may cause air to circulate through passages formed in the parts of the core.
Dated this 24th day of November 1891.
EDWARD K. DUTTON,
1, St. James Square, Manchester.
Improvements in the Production of Hollow Steel Ingots and in
Apparatus therefor.
I EDWARD KENWORTHY DUTTON of the firm of E. K. Dutton & Co. of
5 John Dalton Street, Manchester, in the County of Lancaster, Consulting
Engineers, and Fellows of the Institute of Patent Agents, do hereby declare the
nature of this invention (communicated to me from abroad by Albert Mathies of
23 Fallerstrasse, Hamburg, in the Empire of Germany, Manager) and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement and accompanying drawings:-
My invention relates to the production of hollow steel ingots for use in the
manufacture of hollow shafts tubes and other tubular bodies as is now well under-
stood. In the casting of such ingots cores have been inserted within the mould as
is usual when casting hollow bodies but difficulties have been experienced in
providing cores which would meet all the requirements. It is necessary that such
cores shall be firm enough to withstand the pressure of the metal and shall at the
same time be capable of yielding as the metal contracts or of being withdrawn
before the contraction commences or has proceeded to any great extent.
I employ
cores which can be readily withdrawn and which in some cases can be expanded
before withdrawal so as to exert a pressure upon the setting metal. One form of
core consists of a sheet of thin sheet iron or mild steel coiled into a cylindrical form
the sheet used being of a length amounting to two or more times the circumference
of the required core. By thus coiling up a long thin sheet I am enabled to obtain
sufficient strength in the core at the same time that the core can be readily removed
from the ingot. In place of the coiled core I may use a sectional core provided
with a tapering square, or polygonal central expanding block. The sections may
'be connected with the central block temporarily or permanently by means of
dovetail keys or may have plain faces to meet the faces on the said block. The
joints between the sections may be provided with suitable covering plates. The
ingot may be cast with the core in its contracted form and the expanding block be
afterwards forced downward or inward so as to expand the core thereby compressing
the soft metal, or the metal may be run with the expanding block in position and
the block be withdrawn after a suitable interval. After such withdrawal the core
would be free to contract and the sections could be lifted out.
In order that the nature of my invention may be clearly understood I will
describe the same more fully with reference to the accompanying drawings :-
In the said drawings
Figs. 1 and 2 illustrate the apparatus for casting hollow ingots with the aid of a
coiled sheet metal core.
In the apparatus illustrated by the other figs. sectional expanding cores are used.
Fig. 1 represents a horizontal section and Fig. 2 a vertical section of the
.apparatus.
In these figs. a is the mould which may be of any suitable construction, 6 is the
removable core and c is the space to receive the melted metal.
The core is made by coiling a sheet of thin metal into a hollow cylindrical form
the necessary strength to resist the pressure of the melted metal being obtained by
coiling the sheet metal two three or more times around the mandrel or mould upon
which the core is forined. In the centre of the mould a a hollow core shaft or

page_text: block dis mounted this shaft being less in diameter than the interior diameter of
the core b.
The lower end of this shaft enters a recess or seating formed in the base plate a
and the upper end is fitted to revolve in a bearing formed in the cover plate a² of the
mould. The inner end of the coiled sheet forming the core is bent inward and
attached to the core shaft as indicated, in Fig. 1. The shaft and core are placed
in position within the mould and the cover plate is secured in position. The metal
is run into the mould and allowed to remain until set. The shaft is then rotated so
as to coil upon itself the sheet metal of the core which is thereby stripped from the
ingot so that the latter is free to shrink in cooling.
The core shaft may be turned by hand by means of a cross bar or handle applied
to the bar head or the latter may be formed or provided with a capstan head or be
otherwise suitably adapted to be rotated. In the example the upper end of the bar
is provided with a bevel wheel e with which gears a bevel pinion e¹ which is fixed
upon a shaft which is mounted to revolve in a bearing in a part formed upon or
fixed to the cover plate the shaft being provided with cross handles for with other
suitable means whereby the shaft can be turned and the core bar be thereby rotated
so as to coil up the sheet metal. When the core has thus been stripped from the
ingot, the cover plate a² carrying with it the core bar and core may be removed
from the mould. In some cases or if preferred the core & may be stripped from the
ingot after the latter has been removed from the mould and in such a case or in any
case the core bar d may be dispensed with. The core shaft is preferably hollow as
in the example in order that water or air may be passed through it to prevent
overheating. I do not however claim the use of water or air as novel.
In Figs. 3 and 4 the core consists of five principal parts namely a central tapering
core bar or block of a square form in cross section and four core sections / h.
These sections taper from end to end to suit the taper of the core bar so that when
the inner flat faces of the sections are in contact with the flat faces of the core bar
the outer curved surfaces of the sections will constitute a cylinder which is broken
in continuity by spaces between the sections. These spaces are outwardly closed
by means of covering plates which may vary in form as regards their inner faces
but are outwardly curved to correspond with the sections so that the cylindrical
formation of the core is completed by the said covering plates. It will be seen that
if the central core shaft were forced downward the four sections would be forced
outwardly away from the axis of the said shaft so as to expand the core. When it
is intended to compress the metal of the ingot the metal is run in when the core is
in its contracted form. After a suitable interval the core would be expanded by
driving down the central bar or by forcing it down by hydraulic or screw pressure
or by a dead weight or by suitable means such expansion of the mandrel compressing
the metal as will be readily understood. When this compression of the ingot
metal is not required I may remove the central block prior to the running, and fill
or partly fill the spaces with sand or with wood or with a substance or material
which would furnish a support until the metal had set and would by yielding or by
becoming melted or burnt permit the sections to contract.
Fig. 5 illustrates a core thus prepared for the casting.
Fig. 6 shows a core having six sections and a hexagonal central core bar.
The central core bar is hollow and passages for water or air are formed through
the core sections for the purpose hereinbefore mentioned with reference to Figs. 1
and 2. I may cause air to flow upward or downward through the spaces between
the sections or between the core and the core bar when such spaces are not filled in
the manner herein before mentioned.
Modifications are illustrated by Figs. 7 and 8.
In this example the core sections are connected with the central core bar by
means of dovetail keys which are fixed to or formed upon the bar and enter grooves
of corresponding form in the sections. In this case when the central bar would be
lifted out of the mould it would carry with it the four sections, the first withdrawing
movement of the bar having the effect of contracting the core so as to render it

page_text: capable of being lifted out entire. In the example the contraction of the core is
effected by turning a worm shaft k which turns a nut wheel which engages with a
screw thread formed upon the upper cylindrical end m of the core bar. 1 do not
however confine myself to this or to any method of drawing up or outward the core
bar which might in some cases be pushed up from below by hydraulic pressure or
by other means. A variation in the form of the covering plates is shown in Fig. 7
wherein the said plates consist of curved sheet steel plates each fixed by one side to
one of the core sections. Any suitable form of covering plate may be used for
the purpose. The covering plates in any of the examples might be dispensed with
but in such a case I should reduce the spaces between the sections or fit the sections
close together when preparing for the running the sections forming together a nearly
continuous cylinder the nicks or spaces being closed with sand or loam or with a
suitable material, if necessary or desirable. Such a core would be suitable more
particularly for use when the ingot would be compressed by the expansion of the
core.
The connection of the sections with the central bar or block might be effected by
means of headed screws or studs or by other means so long as the connection
permitted of the sliding of the sections upon the bar to a suitable extent.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1) A core for use in the casting of hollow ingots consisting of a thin sheet of
metal coiled into the form of a hollow cylinder the shell of such cylinder having two
or more thicknesses or layers of the sheet metal as set forth.
2) A core for use in the casting of hollow ingots consisting of a coiled sheet of
thin metal attached by the inner end of the coil to a shaft which can be mounted
within the ingot mould so as to be capable of being rotated substantially as and for
the purposes set forth and indicated.
3) A core for use in the casting of hollow ingots consisting of sections surrounding
and shaped to fit a central wedge bar or block the combination expanding in diameter
when the central bar would be pushed inward and contracting or being free to
contract when the bar would be drawn outward substantially as set forth and
indicated.
•
4) A core for use in the casting of hollow ingots consisting of sections fitting
against the sides of a tapering square, or polygonal shaft or block and connected
therewith by means of keys or parts substantially as set forth and indicated.
5) In the production of hollow steel ingots the use of an expanding core of the
indicated nature to compress or condense the metal of the ingot substantially as set
forth.
6) The combination of parts as set forth and indicated constituting apparatus for
use in the production of hollow nietal ingots.
Dated this 24th day of August 1892.
EDWARD K. DUTTON.