IMPROVEMENTS IN THE MANUFACTURE OF IRON AND STEEL
Year: 1867

page_text: PROVISIONAL SPECIFICATION left by Alexander. Lyman Holley at the
Office of the Commissioners of Patents, with his Petition, on the 27th
February 1867.
I, ALEXANDER LYMAN HOLLEY, of the State, County, and City of New
York, in the United States of America, Mechanical Engineer, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE MANUFACTURE
OF IRON AND STEEL," to be as follows:-
The said Invention consists in a novel mode of and means for casting
ingots and other masses from liquid malleable iron or steel. It is usual, iu
the Bessemer or pneumatic process to run five or six tons of steel out of a
small nozzle in a ladle into as many as twenty or thirty molds to form ingots
of suitable sizes for nails, railway axles, and small forgings. To prevent the
steel from boiling over in the molds, and thus making the ingots unsound or
hollow, it is necessary to frequently stop or check the stream of steel flowing
from the ladle; this frequent closing of the nozzle and the time occupied by
it, and by placing and stopping the ladle over each mold, tends to chill the
steel around and in the nozzle, and to form a scull in the ladle. It is some-
times impossible to close the nozzle tightly or at all in moving the ladle from
mold to mold; scrap and unsound ingots are often produced from this
cause also. In pouring small ingots, especially from the top, the stream of
steel is likely to hit the sides of the mold and to spatter upon them, forming

page_text: scales which are never perfectly united with the body of the ingot, thus
causing seams in the steel when further manufactured; it is also difficult, if
not impossible, to make ingots thus cast of exactly or nearly the required
weight on account of the rising and settling of the steel in the mold, there-
fore an excess of weight, forming more scrap, is usually allowed.
My improvements chiefly consist in remedying these defects to a great
extent by casting two or more ingots in ordinary separate ingot molds at one
pouring or teeming. For this purpose I prefer to place a group of ingot
molds made of cast iron or any suitable material around a central ingot mold
somewhat higher than the others; if they are compound molds I prefer to
hold them together by one or more common bands passing around the group'
and tightened by wedges. All these molds are set upon what I will call a
"distributing bottom," which consists of a box or flask filled with molding
sand or other suitable molding material, in which are molded sprues or
runners connecting the lower end of the central mold with the lower ends of
the surrounding molds, the central mold being open at the top,, and the tops
of the surrounding molds being stopped with suitable vented loam stoppers,
or covered with cast-iron plates coated with loam and properly vented. The
metal is run out of the ladle into the central mold, whence it passes through
tlfe runners in the "distributing bottom" to the surrounding molds; when
the latter molds are filled up to the stoppers the metal continues to rise in
the central mold until it is filled, thus forming a head or riser which promotes
the soundness of the surrounding ingots; the central mold is then closed in
the usual manner. Molds formed from patterns or otherwise in sand, clay,
or other suitable molding material may be set upon and filled from the
distributing bottom" in place of the surrounding ingot molds.
"
To prevent the stream of metal that pours into the central mold from
washing or injuring the said sprues or runners I prefer to mold from a
pattern in the said "distributing bottom" a continuation of the central
mold, and to run the sprues out of the sides of this contiuuation. The lower
part of this continuation, upon which the stream of metal strikes, I prefer to
mold from ground fire-brick or ground crucibles mixed with enough raw
fire-clay to make it plastic; the rest of the "distributing bottom" may be
made of good loam or molding sand; the "distributing bottom" must be
thoroughly dried before the metal is poured into it. When the nietal is
sufficiently cool the molds are removed and the ingots are separated by
breaking off the sprues. The size of the sprues and the number of molds to
be grouped, as described, will depend on the heat and fluidity of the meta

page_text: and upon the weight of the ingots; for an ingot of six or seven cwt. the sprue
may be one and one half inch in diameter if not more than a foot long.
From four to eight ingot molds may be placed around the mold that receives
the metal without making the sprues so long that the metal will chill in
them.
".
:
The distributing bottom" may be molded in any of the suitable ways
practised by founders. I prefer to make the exterior or shell a cast-iron
flask provided with trunnions or ears by which it may be readily handled. In
some cases I dry the "distributing bottoms" in an oven, then set them in the
casting pit, and then set the molds upon them; I prefer, however, to carry
flues from a suitable furnace or furnaces along the casting pit, and to economise
labor by setting the "distributing bottoms" as soon as they are molded to
dry and to be heated over openings in these flues; hot ingot molds may at the
same time be set upon the "distributing bottoms" to assist their drying. By
making two or more flues in different parts of the pit one set of "distributing
bottoms" may be drying while another set is in use, or the " "distributing
bottoms may be permanently placed over flues in the casting pit; these flues
may be heated by steam pipes instead of by hot gases from a furnace. The
ingots that are filled from the "distributing bottom" may be made of exactly
the same weight or of any definite weight by simply regulating the height of
the mold. To make ingots of different weights in the same mold, I prefer
to place loam stoppers of different lengths in the top of the mold; the depth
of the stopper governs the height and weight of the ingot.
My inprovements further consist in casting two or more ingots at one
pouring in the following manner :-I place a group of ingot molds in the pit in
the usual manner; the tops of these molds should be flat, and should be in
the same horizontal plane; upon the tops of these molds I place what I call
a "distributing top," which I prefer to make mold and dry similarly to the
"distributing bottom," herein-before described. The said top consists, by
> preference, of an iron flask filled with molding sand or other suitable molding
material; in which there are formed sprues or runners leading from the sides of
a central cavity or basin into the tops of the ingot molds upon which the
"distributing top" sets. The metal may be run out of the ladle into the
central cavity or basin, from which it will run into and fill the molds below;
I prefer, however, for the purpose of making less scrap and also of making a
high head or riser over the lower molds, to set an ingot mold over this
central cavity or basin, and to make the said cavity or basin a continuation of
the said upper ingot mold.

page_text: The flask that forms the shell of the "distributing top" is provided with
slats or ribs to rest upon the lower molds and to hold up the upper mold.
The "distributing top," like the stoppers or top plates, herein-before described,
is properly vented so that the air and gases may pass out of the lower molds
as the metal fills them.