Improvements in Apparatus and Appliances for the Rapid Determination of Carbon in Steel.
Year: 1891

page_text: Date of Application, 16th Feb., 1891
Complete Specification Left, 16th Dec., 1891-Accepted, 16th Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements in Apparatus and Appliances for the Rapid
Determination of Carbon in Steel.
We, ALEXANDRE TROPENAS of 15 Saint James' Row, Sheffield, Civil
Engineer, and ALFRED ERNEST WELLS of Woodlea, Moorgate, Rotherham,
Steel Manufacturer, both in the County of York, do hereby declare the nature of
the said invention for "IMPROVEMENTS IN APPARATUS AND APPLIANCES FOR
THE RAPID DETERMINATION OF CARBON IN STEEL to be as follows
The object of this invention is to provide the means of quickly determining the
quantity of carbon existing in molten steel made by any pneumatic process at any
period of the operation, and by this means to know exactly when the operation, or
blowing should be stopped, which is not possible by any other apparatus or
appliance known to have been used up to the present time.
We effect these objects by employing apparatus and appliances of which the
following is a description.
The apparatus consists of a small conduit pipe with special mouth and special
swivel joints to allow of easy insertion in and taking out of the pneumatic vessel.
This pipe is provided at its other extremity with an air valve and can be fixed at
any angle and is in communication by other pipes or branches with one, two or
more test tubes. These test tubes are constructed with special bottoms fitted with
one or more valves or with one valve having several thoroughfares, through this
valve or valves is admitted to the test tube; first, a special liquid, through pipes
from a tank conveniently placed for the purpose, secondly the gas from the
conduit pipe or branches, thirdly to allow of the emptying of the test tubes.
The last named tank has also a valve by which the special liquid can be further
regulated to the test tubes.
The special liquid here referred to becomes of a milky appearance when
carbonic acid gas, CO is passed through it, for example, lime water or any other
liquid of similar chemical property.
The mode of applying our improved appliances is as follows:-
Supposing we require the quantity of carbon in a Bessemer converter during the
last period of the operation, we insert in the mouth of the converter the conduit
pipe with special mouth capable of resisting the high temperature of the gases.
We then open the air valve, previously referred to, to emit the air from the conduit
pipe and then close it. As there is a pressure in the converter the gas is driven
through this conduit pipe and thence through other pipes or branches leading to
the test tubes. We then open one of the valves to allow the gas to pass into, say
the first test tube, which has previously been filled with liquid, from the tank, as
already indicated. We then admit gas through the valve in the bottom of the
test tube for a given period, say, for example 10 seconds, this causes the liquid in
the test tube to assume a milky appearance, the density of which is determined by
the percentage of carbonic acid gas passing through it.
Where the pressure in the converter is not sufficient to induce the gas to flow
through the conduit pipes, valves and the liquid, in the test tubes, we employ an
inspirator or other artificial means of drawing the gas through the pipes, valves
and tubes.
For purposes of comparison, we prepare several tests, hereinafter called
standards. In the preparation of these standards we pass through a test tube,
filled with the special liquid as previously explained, the gas from the converter
and at exactly the same time take from converter, by means of a spoon, a sample
of the steel which is afterwards fully analysed, by laboratory tests, when the

page_text: analysis has been ascertained, the percentage of carbon is marked on the test tube,
the milky fluid within which will be comparable in color to the percentage of
carbon contained in the steel at that particular period.
These.standards are continued to a number found to be sufficient, each one being
marked with the exact analysis of its respective carbon etc.
Afterwards each test is compared with the standard most nearly approximating
in color or density to it. This will show at once, by the eye, the percentage of
carbon in the converter. (Note. Only about 10 seconds are required for this
operation.) Explanatory note shewing the relation between the percentage of
carbon in metallic bath and percentage of carbonic acid gas and carbonic oxide in
the gas emitted from vessel.
It is known that the composition of the gas emitted from a Bessemer vessel,
during the operation of blowing, is approximately as follows:-
alus are
marked with the exact analysis of its respective carbon etc.
Afterwards each test is compared with the standard most nearly approximating
in color or density to it. This will show at once, by the eye, the percentage of
carbon in the converter. (Note. Only about 10 seconds are required for this
operation.) Explanatory note shewing the relation between the percentage of
carbon in metallic bath and percentage of carbonic acid gas and carbonic oxide in
the gas emitted from vessel.
It is known that the composition of the gas emitted from a Bessemer vessel,
during the operation of blowing, is approximately as follows:-
1st period 0 TO 4 minutes
.2nd period
3rd period
-
CO 3 to 4 %
Ο
H and N 82 to 87%.
CO* 6%
CO 12 to 18%
H and N 70%.
CO² 2 to 3%
CO 18 to 20 %
H and N 75%.
Last period
-
CO³ 1 to 2%
CO 10 to 12 %
H and N 85 to.90%.
It is not necessary to give an exact analysis, but simply to indicate the general
alterations which take place during the different periods of the operation in
accordance with principles already defined.
In one word, CO is always being reduced from the commencement to the finish
of the blowing operation, whilst CO is increased during the first 3 periods and
then it is quickly but progressively reduced during the last 2 minutes of the
operation.
It is on this well known progression that we have based the principle of our
invention.
The liquid we introduce in the test tube being sensitive to the action of CO*
only, we shall have immediately, by the means before described one instantanecus
analysis of the percentage of carbon in the metallic vessel. It is evident that all
liquid which is sensitive to the influence of CO2 such as lime water, salts of lead
to obtain a white precipitate, or a preparation of the tincture of turmeric or violet
syrup, to obtain a special color etc. can be used for the same purpose.
It is possible that at times the gas from the vessel may not for some seconds
contain the necessary volume of CO to influence sufficiently the liquid in the test
tube (this will occur when pig iron with only a small proportion of carbon is
employed) but this difficulty can be overcome by introducing a small pipe, from the
blowing engine, into the conduit pipe through which a sufficient quantity of air
may be admitted to immediately convert CO into CO².
Dated this 13th day of February 1891.
12 HERER RADFORD
R HERER RADFORD,
Agent for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improvements in Apparatus and Appliances for the Rapid
Determination of Carbon in Steel.
We, ALEXANDRE TROPENAS of 15, Saint James' Row, Sheffield, Civil Engineer,
and ALFRED ERNEST WELLS, of Moorlands, Moorgate, Rotherham, Steel
Manufacturer, both in the County of York, do hereby declare the nature of the
said invention for "IMPROVEMENTS IN APPARATUS AND APPLIANCES FOR THE
RAPID DETERMINATION OF CARBON IN STEEL and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement:-
"
The object of this invention is to provide the means of quickly determining the
quantity of carbon existing in molten steel made by any pneumatic process at any
period of the operation, and by this means to know exactly when the operation or
blowing should be stopped, which is not possible by any other apparatus or
appliance known to have been used up to the present time.
We attain these objects by employing apparatus and appliances in the manner
substantially as illustrated in the accompanying drawings, in which, Fig. 1. (Sheet 1)
is an apparatus consisting of a small conduit pipe, a, with special mouth piece, b,
and special swivel joints (not shewn) to allow of easy inserting and taking out of
the pneumatic vessel. This pipe is provided at its other extremity with an air
valve, C, and can be fixed at any angle and is in communication by other pipes or
branches, a, with one, two or more test tubes, d, d. These test tubes are
constructed with special bottoms fitted with one or more valves or with one valve, e,
having several thoroughfares, through this valve or valves is admitted to the test
tube: first, a special liquid, through a pipe or pipes, h, from a tank, f, conveniently
placed for the purpose, or by preference the liquid can be taken direct from the
tank, to the test tubes, d, d, by an india rubber pipe or pipes, h', as shewn,
secondly, the gas from the conduit pipe, a', or branches, thirdly, to allow of the
emptying of the test tubes.
The last named tank has also a valve or valves g, g, by which the special liquid
can be further regulated to the test tubes.
The special liquid here referred to becomes of a milky appearance or changes
color when carbonic acid gas, CO³, is passed through it, for example, lime water
becomes milky or a solution of litmus and water will become red or any other
liquid of a similar chemical property may be employed.
The mode of applying our improved appliances is as follows:-
Supposing we require the quantity of carbon in a Bessemer converter during the
last period of the operation, we insert in the mouth of the converter, the conduit
pipe with special mouth, b, capable of resisting the high temperature of the gases.
We then open the air valve, C, previously referred to, to emit the air from the
conduit pipe and then close it. As there is a pressure in the converter the gas is
driven through this conduit pipe and thence through other pipes or branches
leading to the test tubes, d, d.
We then open one of the valves, e, to allow the gas to pass into, say the first test
tube, which previously been filled with liquid, from the tank, f, as already
indicated. We admit gas through this valve in the bottom of the test tube for a
given period say, for example 10 seconds, this causes the liquid in the test tube to
assume a milky appearance if lime water is employed, or change to a red color
if a solution of litmus and water is employed, the density or color of which is
determined by the percentage of carbonic acid gas passing through it.
Where the pressure in the converter is not sufficient to induce the gas to flow
through the conduit pipes, valves and the liquid in the test tubes, we employ an
inspirator or other artificial means of drawing the gas through the pipes, valves
and tubes;

page_text: For purposes of comparison, we prepare several tests, herein-after called
standards. In the preparation of these standards we pass through a test tube,
filled with the special liquid as previously explained, the gas from the converter and
at exactly the same time take from converter, by means of a spoon, a sample of the
steel which is afterwards fully analysed by laboratory tests, when the analysis-has
been ascertained, the percentage of carbon is marked on the test tube, the milky or
red fluid within which will be comparable in density or color to the percentage of
carbon contained in the steel at that particular period.
These standards, m, Figs. 1 and 2, are continued to a number found to be
sufficient, each one being marked with the exact analysis of its respective
carbon etc.
Afterwards each test is compared with the standard most nearly approximating
in color or density to it. This will shew at once, by the eye, the percentage of
carbon in the converter.
Note. With a suitably constructed apparatus only about 10 seconds are required
for this operation. Explanatory note, shewing the relation between the percentage
of carbon in metallic bath and percentage of carbonic acid gas and carbonic oxide
in the gas emitted from vessel.
It is known that the composition of the gas emitted from a Bessemer vessel,
during the operation of blowing, is approximately as follows:-
Lat noul
01080 001

page_text: have more .CO' and at same time the difference in CO will be greater in two
consecutive tests. Consequently we claim specially the application of our method,
to all kinds of pneumatic processes blown at or near the top.
It is on this well known progression that we have based the principle of our
invention.
The liquid we introduce in the test tube being sensitive to the action of CO2
only, we shall have immediately, by the means before described one instantaneous
comparative analysis of the percentage of carbon in the metallic vessel. It is
evident that all liquid which is sensitive to the influence of CO* such as lime water
which becomes milky in appearance, salts of lead to obtain a precipitate, or a
preparation of the tincture of turmeric or violet syrup or litmus, to obtain a special
color etc. can be used for the same purpose.
It is possible that at times the gas from the vessel may not for some seconds
contain the necessary volume of CO to influence sufficiently the liquid in the test
tube (this will occur when pig iron with only a small proportion of carbon is
employed) but this difficulty can be overcome by introducing a small pipe from the
blowing engine, into the conduit pipe, a', through which a sufficient quantity of air
may be admitted, to immediately convert CO into CO*.
We consider it is better to take the test only after the "boiling" of the blow,
our experience having found that it is from this moment that the decreasing
progression of CO2 in the gas is perfectly reliable with carbon contained in the
steel.
As a modification of the apparatus and appliances herein described we employ
the following arrangement.
The modified apparatus Fig. No. 3 like that previously described consists of a
small conduit pipe, a', with a special or trumpet shaped mouth, b, and suitable swivel
joints (not shewn) to allow of easy inserting and taking from the pneumatic vessel.
This conduit pipe is always open at the opposite extremity to the trumpet mouth
and is provided with one or more branches, a', each of which can be connected by
an india rubber tube, i, to a nipple, j, of a burette, k.
The burette is made in glass of a total capacity of 100 cubic centimetres
and is provided with a graduated scale in cubic centimetres from zero to 100,
the top of the burette is fitted with a two way cock, l, which in one position
puts the body of the burette in communication with the nipple, j, and in
the other position puts the body of the burette in communication with a funnel, n,
the bottom of the burette is also provided with an ordinary cock or tap, o, and
through this tap water can be put into the burette under pressure by provision from
the tap, p, and india rubber tube, q.
A glass test tube, d, containing a definite solution of litmus and water or other
suitable liquid is placed in a convenient position near the nipple, j, of the burette
and the india rubber tube, i, can be taken off when required from the connection, a²,
and put into the test tube, d, as shewn by the dotted lines.
The mode of applying our modified apparatus and appliance is as follows:-
Supposing we require the quantity of carbon in a pneumatic operation during the
last period, we insert in the mouth of the converter the conduit pipe with the
special mouth, b, capable of resisting the high temperature of the gases and having
previously filled up the burette, k, with water by means of the tube, q, from the
tap, p, the tube, g, is then disconnected from the burette. The branch, a², is now
connected with the nipple, j, we then open the cock, o, to empty the burette, k, and
as the water runs out through the cock, o, the gas from the vessel is aspirated into
the burette, k, and when all the water is run out of the burette, it is left full of gas
from the converter, or in other words the burette will then contain 100 cubic
centimetres of gas drawn from the converting vessel.
We next take off from the branch a³, the end.of.the tube, i, and put this end into
the test tube, d, which as already described contains a solution of litmus and water
or other suitable agent, we then re-connect tube, q, with the cock, o, at the bottom
of the burette and on opening the communication between the water main, p, and

page_text: the burette the gas is expelled upwards from the burette through the cock, l, which
has been previously opened, to the nipple, j, and thence through the pipe, i, to the
test tube, d, through the special liquid. As soon as the burette, k, is filled with
water we shut the cocks, o, and, p, or both.
Under the influence of CO' the special liquid in the test tube, d, has been altered
in color or density we compare this with the previously prepared standards as
already explained and ascertain by comparison the percentage of carbon contained
in the steel in the converter, this operation occupying from 10 to 20 seconds.
As a further modification in the method of ascertaining the quantity of CO*
contained in the gas drawn from the converting vessel we employ the last named
apparatus and appliances as illustrated in Fig. 3, but without employing the color
test, in order to do this we fill the burette, k, with gas from the vessel as herein
previously explained, the funnel, n, having been filled with a solution of caustic
potash and water, (a solution of about 5 per cent., KO will do), we then open the
tap, l, to introduce the solution into the burette and let it run in until it stops of
itself and by observing the division on the scale where the level of the potash
solution has risen in the burette, we at once ascertain the percentage of CO2
contained in the gas because the potash having absorbed all the CO2 of the gas the
volume occupied by the KO solution, represents exactly the volume of CO'
absorbed.
In using the last named modified process it will be necessary to have previously
prepared a table of comparative analyses by taking from the vessel at fixed periods
during the operation of blowing simultaneously a sample of gas and a sample of
metal, the latter being treated to a complete laboratory analysis for the percentage
of carbon, and the gas being tested by the KO solution as herein described for the
percentage of CO2, then in future operations the percentage of carbon in the steel
during any given period of the blowing operation may be determined by a
comparison with the table so soon as the percentage of CO³ contained in the gas at
the same period has been ascertained.
Having now particularly described and ascertained the nature of our inven-
tion and in what manner the same is to be performed we declare that what we
claim is,
1. In apparatus and appliances for the rapid determination of the quantity of
carbonic acid gas contained in the gas in a converting vessel by any pneumatic
process for the manufacture of steel or ingot iron. The particular arrangement
and combination of parts and appliances and the methods employed therewith by
means of which the percentage of carbon in the molten metal at any given period
in the blowing operation may be determined by comparison with the percentage of
carbonic acid gas contained in the gas taken from the vessel and tested during the
corresponding period of the blowing operation referred to, in the manner and for
the purposes substantially as herein described and illustrated in Figs. 1 and 2 of
the accompanying sheet of drawings.
2. In apparatus and appliances for the rapid determination of the quantity of
carbonic acid gas contained in the gas in a converting vessel by any pneumatic
process for the manufacture of steel or ingot iron. The particular arrangement
and combination of parts and appliances and the methods employed therewith by
means of which the percentage of carbon in the molten metal at any given period
in the blowing operation may be determined by comparison with the percentage
of carbonic acid gas contained in the gas taken from the vessel and tested during
the corresponding period of the blowing operation referred to in the manner
and for the purposes substantially as herein described and illustrated in Fig. No. 3,
of the accompanying sheet of drawings.
Dated this 15th deve of December 1901
R. HEBER
RADFORD,
Agent for the Applicants.