AN IMPROVEMENT IN THE MANUFACTURE OF STEEL
Year: 1884

page_text: PROVISIONAL SPECIFICATION.
I PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane in the County of
Middlesex, Fellow of the Institute of Patent Agents do hereby declare the nature
of said invention for "AN IMPROVEMENT IN THE MANUFACTURE OF STEEL"
a communication to me from abroad by Lilian Eliza Thomas of 61 Avenue Marceau,
Paris, in the Republic of France, Spinster to be as follows:--
This invention relates to an improvement in the manufacture of basic dephos-
phorised steel and facilitates and renders more certain and uniform the production
of steel with exceedingly low percentages of Phosphorus.
By the present invention this result is obtained by adding to the Basic converter
or furnace after the carbon is almost, or better completely, removed from a charge
of phosphoric iron, a small quantity, not generally exceeding one hundred weight
per ton of metal, of carbonate (or hydrate) of soda which should be compressed into
cakes, preferably with oxide of iron, magnesia or lime; or it may be in part or
altogether blown in.
. I prefer that this addition should be made after a great part of the Basic slag,
already charged with phosphorus, has been poured off, and just after a fresh
addition of lime has been made. By this means a more liquid and penetrating
Basic slag is obtained in which the last traces of phosphorus, which are so
tenaciously held in the ordinary process, are readily removed. I do not wish to be
understood to claim the production of a sing consisting wholely of phosphate of
soda, but merely the above described modification of the Basic or Thomas Gilchrist
process.

page_text: COMPLETE SPECIFICATION.
"
I PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane in the County of
Middlesex Fellow of the Institute of Patent Agents do hereby declare the nature
of said invention for "AN IMPROVEMENT IN THE MANUFACTURE OF STEEL
a communication to me from abroad by Lilian Eliza Thomas of 61 Avenue Marceau
Paris in the Republic of France, Spinster and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
This invention relates to an improvement in the manufacture of Basic Dephos-
phorized steel and facilitates and renders more certain and_uniform the production
of steel, with exceedingly low percentages of Phosphorus. By the present invention
this result is obtained by adding to the Basic Converter or Furnace after the carbon
is completely removed from a charge of phosphoric iron, a small quantity (not
generally exceeding one hundred weight per ton of metal) of carbonate (or hydrate) of
soda free from all sulphur compounds, on which account ammonia soda is preferably
used, and this should be either added melted or compressed into cakes, preferably
with oxide of iron, magnesia or lime or it may be in part or altogether blown in.
This addition should be made when the greater part of the Phosphorus has been
removed from the metal, and when as much as possible of the resulting slag has
been poured off, a fresh addition of lime may be made at the same time. By this
means a more liquid or penetrating basic slag is obtained by which the last traces
of Phosphorus which are so tenaciously held in the ordinary process aro readily
removed or steel produced containing only .02% and under of Phosphorus. I do
not wish to be understood as claiming the production of a slag consisting wholely
of phosphate of soda, but merely the above described modification of the Basic or
Thomas-Gilchrist Process.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to me
by my foreign correspondent I declare that what I claim is
In the manufacture of steel, the addition to a partly dephosphorized charge
of metal in a basic lined converter of a small amount of carbonate or hydrate of
soda free from sulphur compounds, for the purpose of removing the last traces of
Phosphorus substantially as set forth.