Improvements relating to the Casting and Working of Metals and to Apparatus for use in connection therewith.
Year: 1891

page_text: Date of Application, 13th Mar., 1891
Complete Specification Left, 10th Dec., 1891-Accepted, 16th Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements relating to the Casting and Working of Metals and
to Apparatus for use in connection therewith.
I, WILLIAM ELLIS MAY, of 45, Fulham Park Gardens, in the County of
London, Civil Engineer and Naval Architect, do hereby declare the nature of this
invention to be as follows :—
My invention relates to the casting and working of metals, and has for its object
to prevent air from being confined or imprisoned in such metals.
According to my invention casting, forging, rolling, coiling and other operations
are performed in as perfect a vacuum as possible, and for this purpose I provide a
chamber (hereinafter referred to as the "working" chamber) which can be
hermetically closed and from which the air can be exhausted.
In order to permit the air to be quickly exhausted from the working chamber I
advantageously provide a series of chambers from which the air can be exhausted
and which are in connection with the working chamber, suitable valves being
provided for establishing communication between such vacuum chambers and the
working chamber.
In order to pour molten metal into the working chamber I provide an inter-
mediate chamber on the walls of the said working chamber, and construct the same
with suitable valves.
To enable forging, rolling, coiling and other operations to be accomplished the
rod of the steam hammer and the rods for manipulating the material are passed
through stuffing boxes in the walls of the working chamber.
1001
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements relating to the Casting and Working of Metals and
to Apparatus for use in connection therewith.
I, WILLIAM ELLIS MAY, of 45, Fulham Park Gardens, in the County of
London, Civil Engineer, and Naval Architect, 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:-
My invention relates to the casting and working of metals, and has for its object
to prevent air or other gases from being confined or imprisoned in such metals.
According to my invention casting, forging, rolling, coiling and other operations
are performed in as perfect a vacuum as possible, and for this purpose I provide a
chamber (hereinafter referred to as the "working" chamber) which can be
hermetically closed and from which the air can be exhausted.
In order to permit the air to be quickly exhausted from the working chamber I
provide a series of chambers from which the air can be exhausted when required
and in any desirable manner and which are in connection with the working chamber.
(the said chambers being hereinafter referred to as store vacuum chambers) valves
being provided for controlling the communication between such store vacuum
chambers and the working chamber.
In order to pour molten metal into the working chamber I provide an inter-
mediate chamber on the walls of the said working chamber and construct the same
with suitable valves

page_text: To enable forging, rolling, coiling and other operations to be accomplished the
rod of the steam or other hammer and the rods for manipulating the material are
passed through stuffing-boxes in the walls of the working chamber.
:―
To enable my invention to be fully understood I will describe how it can be
carried into practice by reference to the accompanying drawings, in which :-
Figures 1 and 2 are respectively a plan and a vertical section of apparatus
suitable for use in casting metals in a vacuum according to my invention :
Figures 3 and 4 are respectively a vertical section and a horizontal section of a
detail of the same:
Figures 5 and 6 are respectively a vertical section and a horizontal section of a
modified arrangement of a portion of the said apparatus :
Figure 7 is a vertical section of apparatus suitable for use in forging metals in
a vacuum according to my invention; and,
Figure 8 is a section of a detail of the same.
Similar reference letters indicate similar or corresponding parts throughout the
drawings.
a is the "working" chamber, and b, bare the store vacuum chambers which are
separately connected to the chamber a, and from which the air is exhausted by a
suitable exhauster or air-pump at c, the said store vacuum chambers b, being
preferably placed below the surface of the ground, as shewn most clearly in
Figure 2. d, d are pipes for establishing communication between the store vacuum
chambers, and the chamber a, and ', d' are the valves for controlling such
communication.
The chamber a is provided with doors (not shewn) adapted to be hermetically
Bealed and with glass windows which are advantageously made double with a
vacuum space between and with a valve in the frame of the inner pane adapted to
close instantaneously if the outer pane is broken.
The operation is carried out in the following manner, that is to say, the working
chamber a is hermetically closed, and then one of the store vacuum chambers' b, b
(from which the air has been previously exhausted by the pump at c or by other
suitable means) is placed in communication with the said working chamber by
opening its valve d', thereby allowing the air in the said working chamber to
expand into the store vacuum chamber, whereby its density is reduced. The valved
is now shut and communication is established between the chamber a and a second
store vacuum chamber and then the communication is shut off, and the third store
vacuum chamber is placed in communication with the working chamber, so that a
close approximation to a vacuum is very rapidly obtained in the said chamber a
and work can at once be carried on therein.
This method of obtaining a vacuum will be readily understood from the following,
assume each of the store vacuum chambers b, b to have a cubical capacity nine
times greater than that of the working chamber: if now the air in the chamber a
is allowed to enter the first store vacuum chamber b, the air in the said chamber a
will be reduced to one tenth of its original pressure, that is to say, from fifteen pounds
per square inch to 1.5 pounds per square inch, and when the first store vacuum
chamber is cut off and the second store vacuum chamber opened the pressure of the
remaining air in the working chamber will be reduced to one hundredth of its
original pressure, viz., to 15 per square inch and when the second store vacuum
chamber is cut off and the third store vacuum chamber opened, the pressure will
again be reduced to one thousandth, that is to say, to "015 per square inch. It will
thus be understood that with a series of store vacuum chambers the total capacity
of which is twenty seven times that of the working chamber it is possible to reduce
the pressure in the latter to one thousandth (1000) of the atmospheric pressure, or
to less pressure if a greater number of smaller store chambers are used whereas, if
a single store vacuum chamber capable of producing the same result were employed,
it would require a capacity nine hundred and ninety nine times greater than that of
the working chamber.
is the intermediate chamber arranged on one wall of the working chamber a and

page_text: used when casting, the said intermediate chamber being connected by pipes e¹, e¹ to
the pipes d, d and the store vacuum chambers b, b, the passage through the said
pipes e, e being controlled by valves e', e. As shewn in Figure 2 the intermediate
chamber e is provided with valves f, g, one of which serves to permit the molten
metal to flow from a hopper h into a hopper i, whilst the other serves to allow the
metal to flow from the hopper i into the chamber a. Each of the said valves, one
of which is shewn drawn to an enlarged scale in Figures 3 and 4, is advantageously
formed with a metal frame f¹ in which is held a fire-clay face for contact with
the molten metal. is a shoot for conducting the molten metal from the hopper i
to a mould in the chamber a.
In this arrangement the valve is first opened and the molten metal is poured
from the ordinary ladle t into the hopper / from whence it passes into the hopper i.
The valve is then closed and communication established between the intermediate
chamber e and the store vacuum chambers 6, by the valves e, e² (in a similar
manner to that hereinbefore described in connection with the chamber a) so as to
exhaust the air from the said chamber e and consequently from the metal in the
hopper i, and at the same time the chamber a is exhausted of air as hereinbefore
described. The valves e², e³ and d', d' are then closed, and the valve g is opened so
as to allow the molten metal to run into the mould k
To allow of the escape of the air contained in the sand around the mould /
without injury to the latter, I advantageously arrange in the sand perforated.
pipes m, m.
I sometimes provide for introducing the ladle or shank containing the molten
metal directly into the chamber e, as illustrated in Figures 5 and 6, so that I can
pour the molten metal directly into the shoot j. In this case I dispense with the
hoppers and i and the valve f, and provide an opening in the chamber e sealed
by a door n, through which opening the ladle can pass into the chamber and be
suspended therein, as shewn.
The shoot, as shewn, is provided with a toothed rack o underneath to enable it
to be moved by a pinion p operated by a hand-wheel outside the chamber a, to
place it beneath the ladle to receive the molten metal, the opening of the valve g
being formed large enough to allow of the passage of the said shoot.
To enable the ladle to be tipped to pour the metal into the shoot I advantageously
provide it with a gear-wheel with which gears a pinion g'. The spindle of the
pinion g¹ is formed with a square end so that it can engage with a correspondingly
shaped opening in a key provided with a hand-wheel, the said key working
through a stuffing-box, so as to enable it to be moved into engagement with and
turn the said spindle when the ladle is in the chamber e.
In Figure 7, the chamber a is shewn in conjunction with a hammer such as a
steam-hammers for forging, and in this case the rod of the hammer is arranged
to work through a stuffing-box on the said chamber. t is the usual bar for
turning the forging when under the hammer, the said bar being passed through a
stuffing-box t¹ and advantageously connected by bolts and nuts to a flange upon a
bar welded to the metal to be forged. u is a rod which serves to support the weight
of the turning bar tand the forging in a well known manner, the said bar passing
through a stuffing-box u' in the top of the chamber a. The stuffing-boxes t¹ and u¹
are each advantageously formed in two parts, arranged to slide in directions at
right angles to one another to provide for the necessary movement for enabling
forging to be properly handled. Figure 8 represents a section (at right angles to
the section shewn in Figure 7) of the stuffing-box u' and its connected sliding
portions.
In the manufacture of coils, for instance in making the coils for a piece of
ordnance, the metal to be coiled is passed through a trough or shoot, the outer end
of which is provided with an air-tight door while the inner end is open to the
chamber a in which the coiling machinery is arranged. After coils have been
made as described, the said coils may be forged or compressed in vacuo as herein-
before described.

page_text: Although I have described only a single working chamber in connection with the
store vacuum chambers it is to be understood that two or more of such working
chambers may be arranged in conjunction with one set of store vacuum chambers,
in one of which, say, work is proceeding whilst in another or others preparations
are being made. In Figure 1 a indicates a second working chamber.
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. The method of preventing the imprisonment of air and other gases in metal
castings, forgings and the like by pouring or working the metal in a chamber or
chambers, from which the air can be promptly exhausted by means of a store
vacuum chamber, or a series of the same, adapted to le placed (successively when
a screw is employed) in communication with the working, chamber or chambers,
substantially as described.
2. The combination with a chamber or chambers in which metals are worked, of
a series of store vacuum chambers from which the air must be exhausted previous
to. working, and which when successively placed in communication with the
working chamber or chambers serve to promptly produce a vacuum therein,
substantially as, and for the purpose, described.
3. The combination with a chamber or chambers in which molten metal can be
poured or worked in the manner referred to in Claim 1, of another chamber or
chambers upon its walls for receiving the molten metal prior to its entry into the
said working chamber or chambers, substantially as described.
Dated the 10th day of December 1891
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.