A NEW AND USEFUL IMPROVEMENT IN THE MANUFACTURE OF STEEL
Year: 1885

page_text: I, WALTER EDWARD WYNNE, of 40 Chancery Lane, in the County of Middlesex,
Solicitor, do hereby declare the nature of my invention for "A NEW AND USEFUL
IMPROVEMENT IN THE MANUFACTURE OF STEEL," and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement:
My improved process of manufacturing ingot iron or steel by the pneumatic
process, while especially adapted to the manufacture of soft or low carbon steel, may
be employed in the production of other grades higher in carbon. It is well known
in the art that Bessemer metal or steel containing over 12 per cent of phosphorus
is unfit for most industrial purposes. Consequently when an ore contained more
than 06 per cent of phosphorus, it was not suitable for use in the manufacture of
pig metal for use in the Bessemer process as heretofore practised, unless subjected
to the expensive and troublesome basic or other dephosphorizing process.
At least
four fifths of the ores in use contain too much phosphorus for making Bessemer
pig, and are consequently cheaper than those applicable thereto.-Furthermore
there are enormous deposits of iron ore on the American Continent and elsewhere,
which have heretofore been considered entirely worthless, owing to the high
proportion of such impurities as phosphorus, sulphur, etc, contained therein, which
rendered it impossible to produce marketable iron therefrom by any of the processes
mentioned or known. By my improved process, I am enabled to produce a very
superior metal by the use of cheap cold or red short pig iron made from such
ores, without dephosphorizing, which metal is applicable to many uses to which
Bessemer metal has not been heretofore applied, and is much better for many
purposes than wrought iron, while at the same time it is much cheaper than the
latter.
Briefly stated my invention consists in desiliconizing phosphoric pig iron in the
pneumatic or like process by oxidizing the metal and immediately removing the
slag resulting from said oxidation.
My improved process may be carried on in a stationary converter having one
or more tuyeres extending horizontally through its sides at proper intervals, prefer-
ably at or about midway of the height of the column of metal in the converter, a
cinder notch about eighteen or twenty inches above the metal line, and means for

page_text: supplying a mild blast, say, of six or eight pounds pressure, or otherwise regulating
the same as regards heat and pressure.
While I speak of a stationary converter, I do not limit myself thereto, because,
as is evident to those skilled in the art, my process may be carried on in a tipping
converter, ladle, open-hearth, or other vessel or furnace, having means for tapping
off the slag, where the metal can be subjected to the desiliconizing and decar-
bonizing action of a blast of air or like agent, as will be understood.
I will now describe the process as it has been practised by the said Henry
William Oliver Junior and James Porter Witherow, in the stationary converting
vessel hereinbefore particularly mentioned.
A charge of, for example, say 3,400 pounds of molten pig metal, containing say
1.8 per cent of silica and 55 of phosphorus, is put into the converter. As soon as
the metal begins to flow into the converter, the blast is gradually turned on, until,
when the entire charge has been introduced, the maximum pressure, which is from
six to eight pounds, is attained. The pressure of the blast is then slowly reduced
to about five pounds, as the metal becomes more fluid. The effect of the blast
upon the metal is to oxidise a portion of the same, thereby forming a base with
which the silica unites, producing a slag containing the silica, which, being lighter
than the metal, rises and is separated therefrom.-The action of the blast causes
the charge to foam up until in five or six minutes the slag begins to flow out at the
cinder notch, which flow will continue for one or two minutes.
When it ceases,
the cinder notch is topped up with clay, and the blow is continued until the flame
drops, which indicates that the carbon has been consumed, a period usually of
about five or six minutes. The fluid metal is then tapped off as quickly as possible
into a ladle, and, if desired, is recarburized by the addition of a sufficient quantity of
ferro-manganese, preferably heated, or other suitable recarburizer. The manganese
of the addition has its usual functions. The metal is then poured into the ingot
moulds.
The average of a number of analyses of the slag which is run off during the
blowing of a charge of the character aforementioned, shows that it has the following

page_text: Its working qualities are, perfect ease of welding; extreme ductility, spreading
freely; and absence of tempering properties.
It is particularly adapted for use in the manufacture of nail plate, tacks spikes,
rivets, bolts, chains, shovels, spades and all kinds of spamping ware, wire rails, crow
bars, harrow-teeth, wood-chopper's wedges, picks, mattocks &c pipes, tubes, flues,
tin plates, and slieets tank and boiler iron, and all kinds of black-smithing and
merchant iron.
With regard to the working qualities above mentioned the metal being low in
carbon, possesses a constant welding property, which is not present in other low
steels, and when it is made from Bessemer pig, containing from 10 to 12 per cent
of phosphorus, its welding properties are equal to the best Swedish iron or the,
finest open-hearth steel. For welded shovel blades, which is one of the most
thorough welding tests in use perfect results are obtained with steel made by my
process, containing 35 per cent of phosphorus and 12 per cent of sulphur. For.
nail plates, the best results are obtained from a moderately cold short pig. The
nail plate made from pig iron containing 5 per cent of phosphorus is better than-
that made from the best Bessemer stock, the latter lacking the desirable stiffness.
which the former possesses.
The important features of my process are the treatment of the phosphoric metal
as described, and the tapping off or otherwise removing the slag containing the
silica as soon as it is formed.
By this process I obtain a product practically free from oxide of iron and gases,
which produce piping, and practically free from silicon, and containing about the
same per centage of phosphorus as was in the charge I obtain uniformity of
product and a minimum waste of magnanese, as there is little or no oxide of iron,
present in the charge when tapped The process is applicable to use with any pig
metal, whether containing much or little phosphorus but as has been stated, it is.
particularly advantageous with phosphoritic pig, because it, enables it to be used'
for the production of an improved ingot iron or steel, whereas before, this material
was unfit for general use without dephosphorization.
When starting with a cold cupola and a fresh converter I prefer to use about
2 per cent of silicon for two or three heats, and then reduce it to 16 or 1.7 per
cent, or thereabouts This can be dono by adding a proper quantity of cast, or
wrought iron, or steel scrap, and if the charge is working too hot, the temperature
can be reduced by adding such scrap either in the cupola or converter as the case
may be.
When steel is desired, the amount of ferro-manganese or other recarburizer
added, will, of course, depend upon the quality of steel desired. For very soft
steel, about 8 per cent of "84 per cent" ferro-manganese, is ordinarily used.
A large number of analyses demonstrates that the process gives remarkably
uniform results. The carbon and silicon are almost completely eliminated
especially the latter, as in no case have I found more than a trace. No appreciable
amount of oxide of iron has been found in the resultant steel, and the satisfactory
working of the steel is to a considerable extent attributable to its absence.
The phosphorus may be utilized as a steelifying agent for iron in place of silicon
or carbon which have heretofore been considered essential to the production of
steel, and in proportion as the other metalloids are reduced or eliminated this
property of the phosphorus is utilized, so that the necessity of the final additions
of carbon and manganese, heretofore used in the basic and other oxidizing processes,
is more or less obviated. If it is desired that the steel should contain these
elements as well as the phosphorus they may be added in quantities to suit the
particular grade of metal required, as will be understood. The presence of the
phosphorus assists in keeping up the heat of the bath after the elimination of
the silicon and carbon and also imparts to the resultant product, hardness, stiffness,
and rigidity, properties of value for many uses in the arts, while it has been found
that it does not detract from the working or malleable qualities of the metal.

page_text: I do not limit myself to the use of a stationary converter, but claim the right to
use my improved process in any apparatus suitable therefor, as hereinbefore stated.
One of the products of my process is a steel or iron high in phosphorus low in
carbon, and practically free from silicon, which I denominate "phosphor steel."
It can be made from cheap cold or red short pig produced from high phosphorus
ores, which product is remarkably adapted for the purposes bereinbefore enumerated.
By high in phosphorus I mean from 15 upwards. The usual product running
from 40 to 60 per cent, and by low in carbon I mean 10 or less. I do not limit
the use of my process to the production of this material alone, but also claim it
broadly for desiliconizing, and for the production of material containing other per
centages of carbon.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is
1. The process of purifying a charge of molten pig metal which consists in
blowing or oxidizing the metal as described and removing the slag during and
without interrupting the blow substantially as and for the purposes described.
2. The process of making phosphor steel herein described, which consists in
blowing the charge of molten pig metal high in phosphorus and removing the
slag containing the silicon when formed, substantially as and for the purposes
described.
3. The process of making phosphor steel herein described which consists in
blowing a charge of molten pig metal high in phosphorus, removing the slag during
the carlier period of the blow, and continuing the blow until the carbon is
consumed.
4. Phosphor steel, practically free from silicon and low in carbon, substantially
as described.