IMPROVE- MENTS IN THE MANUFACTURE OF SHEAR STEEL
Year: 1861

page_text: LETTERS PATENT to Richard Archibald Brooman, of 166, Fleet, Street,
in the City of London, Patent Agent, for the Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF SHEAR STEEL."-A communication from
abroad by Wilhelm Spielfeld, of Unna, Westphalia.
Sealed the 26th September 1861, and dated the 28th March 1861.
PROVISIONAL SPECIFICATION left by the said Richard Archibald Brooman
at the Office of the Commissioners of Patents, with his Petition, on the
28th March 1861.
I, RICHARD ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of
London, Patent Agent, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF SHEAR STEEL," (communicated to me
from abroad by Wilhelm Spielfeld, of Unna, Westphalia,) to be as follows:-
Steel obtained by the process of puddling, and known as puddled steel and
steel iron, is found not to answer all the purposes to which it might be applied
for want of uniformity and homegeneity; puddled steel as well as raw steel is
therefore either formed into cast steel, or by refining into shear steel.
Now, this Invention consists in protecting puddled steel and raw steel
against the action of the gas developed from the fuel, as well as against the
action of atmospheric air, while the puddled or raw steel is exposed to welding
heat, or the highest heat which it can stand without melting. For this purpose
lumps or piles of puddled steel or of raw steel are placed in retorts or vessels

page_text: made of fire-proof materials, I close the opening into the retort or vessel by a lid
with a sight hole in it, and place retort or vessel in a furnace to be heated, by
preference, I take retorts or vessels of prismatic form. The lid should cover
the opening into the retort or vessel as accurately as possible. The sight hole
in the lid communicates with a sight hole in the furnace door, so that the
workman can at any time watch the steel within the retorts or vessels without
opening the door of the furnace or the lid of the retort. When the steel in
the retorts or vessels has become heated to welding heat, or the highest
heat which it can stand without melting, its surface presents a silver-like
appearance, and the interior of the retort or vessel appears of a bluish white
color. The time during which the steel is kept in this state of heat must not
be too short, and cannot be too long, provided. that the heat be not increased
to such a degree as will fuse the steel. After some time, which experience
will dictate, the steel is taken out of the retort or vessel and hammered and
rolled, and the result is a highly improved steel, called shear steel, applicable
'for cutlery, wire plates, and other purposes.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Richard Archibald Brooman in the Great Seal Patent Office
on the 28th September 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of London, Patent
Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing, date the Twenty-eighth day of March, in the year of our
Lord One thousand eight hundred and sixty-one, in the twenty-fourth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Richard Archibald Brooman, Her special licence that
I, the said Richard Archibald Brooman, my executors, administrators, and
assigns; or such others as I, the said Richard Archibald Brooman, 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 and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE
MANUFACTURE OF SHEAR STEEL," (communicated to me from abroad by Wilhelm
Spielfeld, of Unna, Westphalia,) upon the condition (amongst others) that I,

page_text: the said Richard Archibald Brooman, my executors or administrators, by an
instrument in writing under 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 Richard Archibald Brooman, do hereby
declare the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
.
:
It has been found that steel obtained by puddling, and known as puddled
steel and steel iron does not answer all the purposes to which it might be
applied for want of uniformity and homogeneity; puddled steel as well as
raw steel is, therefore, formed into cast steel, or by refining into shear steel.
Now, this Invention consists in protecting puddled steel and raw steel from
and against the action of the gases developed from the fuel, as well as against
the action of atmospheric air while the puddled or raw steel is exposed to
welding heat, or to the highest heat which it can stand without melting, in
order to convert it into what is termed shear steel. For this purpose I place
lumps or piles of puddled steel, or of raw steel into retorts or vessels made of
fire-resisting materials, such, for instance, as those used in the manufacture of
crucibles employed in the conversion of iron into steel, and in the melting of
metals. I close the opening into the retort by a lid with a sight-hole in it,
and place the retort in a furnace to be heated. The form of the retorts will
depend on the manner in which they are heated, as also on the position which
they occupy in the furnace; they may be either conical, or like a crucible, or
cylindrical, or prismatical, preference, however, is given to retorts of a
prismatical form. The position of the retorts in the furnace may be either
horizontal, vertical, or inclined. Sometimes, and especially if very large
lumps or piles of steel are to be operated on, the retort is constructed by
placing an arch upon a base, and carefully luting the joints with fire-resisting
cement or powder. The lid or cover should fit the opening into the retort ans
accurately as may be, but should crevices be accidentally left around the lid,
no gas or air will enter to injure the steel in the retort as long as there is no
opening or crevice in any other part. The sight hole in the lid should com-
municate with a sight hole in the furnace door, to enable the workmen to
watch the steel within the retort without opening the door of the furnace, or
the lid of the retort. The furnace must be heated to such a degree that the steel
within the retort reaches welding heat, and then it must be closely watched,

page_text: and care must be taken to prevent the heat reaching the melting point of
steel. When the steel in the retorts has become heated to welding heat, or
the highest heat to which it can be exposed without melting, its surface
presents a silver-like appearance, and the interior of the retort assumes a
bluish white color. The time during which the steel is kept in this state of
heat must not be too short, and cannot be too long, because the steel being
protected against the action of the gases devoloped from the fuel, and of
'atmospheric air, will not be injured, provided, as before stated, that the heat
be not increased to such a degree as will fuse the steel. After some time,
which experience will dictate, the steel is taken out of the retort and hammered
and rolled. The steel resulting from the treatment herein described is
applicable for cutlery, wire plates, and other purposes.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that I mean by the term
'puddled steel, all such as contains a sufficient quantity of carbon for being
converted into shear steel, by the means herein-before described; and that I
'claim manufacturing shear steel by enclosing raw steel and puddled steel, or
either, in retorts or vessels, and submitting the same in furnaces to welding
heat, or to the highest heat to which the steel can be exposed without melting,
substantially in manner and for the purpose herein-before described.
In witness whereof, I, the said Richard Archibald Brooman, have
hereunto set my hand and seal, this Twenty-seventh day of September,
One thousand eight hundred and sixty-one.
R. A. BROOMAN. (L.S.)