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International Engineering Congress (1901 : Glasgow.

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him.

The meeting was then adjourned.



WEDNESDAY, 4th SEPTEMBER, 19O1.

Mr. WILLIAM WHITWELL, Chairman, in the Chair.



"THE CORRECT TREATMENT OF STEEL."
Paper by C. H. RIDSDALE.



Abstract.

THIS paper, which is one of considerable length, is divided into
six sections. The following is a synopsis of the contents :

SECTION I.

Preliminary Remarks. Much has been learnt of late as to how
certain conditions in steel are brought about, but the knowledge is
not being widely used, probably because it is not clearly connected
with practice.

Objects of the Paper. The author tries to describe, in simple,
practical terms, what is known. He also formulates certain views
and asks for information and discussion as to the control exercised
by the maker and the user, their responsibility, tests, and processes.

SECTION II.

The effect of Composition and Initial Treatment as compared
with Subsequent Treatment.

(a) Considered generally, as to what is possible. The importance
of composition apart from treatment has been overrated. Later
treatment often outweighs composition and initial treatment, and
the maker can do nothing to provide against this. Twist tests
quoted show that rolling hardness outweighs 0.15 per cent,
carbon, and 0.40 per cent, manganese, while the purest and best
steel fails when treatment is unsuitable, and irregular or impure
steel stands if the treatment is right. German and American steel
runs up to o.io per cent, and 0.14 per cent, phosphorus, and some-
times the sulphur is high. Steel users should take as great pains to
control treatment as the makers do to control composition.

(b) As to what is likely in the ordinary working up Much steel
is worked up by separate users, who do not care to trouble about
properties of steel, but simply want to shape it with the least
possible cost. This the use of wrong quality for untried purposes,
or by works using chiefly iron indiscriminate treatment, and other
causes, all tend to develop faults, often only in a small proportion,



196 THE CORRECT TREATMENT OF STEEL.

but discrediting the whole; yet the user seldom thinks of
irregularity in his treatment as the cause, but throws the onus on
the maker.

SECTION III.

Can the maker do more than at present, and, on the other hand,
is it worth the user's while to try what' he can do ? The maker can
supply the most suitable composition when informed what pro-
cesses the steel must undergo, but any slight further degree of
purity attainable, whilst adding to the cost of production, would not
improve the quality nearly so much as the means ready to hand
viz., for the user to study the character of each steel, and treat
it discriminately. The best treatment may be quite easy.

SECTION IV.

In this Section are discussed : the condition of steel at different
temperatures: the cooling of steel: steel molten to critical point:
critical point: below red heat: blue heat the state of minimum
plasticity: below blue heat: the reheating of steel: changes in the
grain and " cement," whilst reheating.

SECTION V.

This section considers samples of processes and treatment which
steel must undergo', including: treatment by the maker: rolling
ingots: finishing temperature of material to be reheated before
further treatment immaterial: rails: medium sections tend to finish
right, heavy sections too hot, light sections too cold; these can be
controlled somewhat by the rate of cooling: girders etc. finishing
temperatures dictated by tests required: plates much the same:
bars for cold shearing these should be finished fairly hot, and not
chilled in any way.

Treatment by the user: rolling after rejheating, reheat as
rapidly as practicable for the mass, but all througn avoid '' soaking "
if there is any delay: avoid burning and over annealing: the best
temperatures can only be ascertained by experiment.

The Forge: forgings should be worked out while hot enough
for work to penetrate the mass : strains through unequal or partial
heating can be removed by reheating without work: drop forg-
ings, which are often finished too hot, should be reheated to break
up the grain.

The Blacksmith's Shop : forgings and weldings. avoid putting
a nice finish at low temperatures : parts heated to welding without
work should be reheated: the use of flux is explained: this latter
is most desirable: tubes, these are difficult to avoid burning or
overheating when making thin tubes.

Gas Cylinders and other welded goods: if only the part heated
to welding receives work, these should be reheated.



THE CORRECT TREATMENT OF STEEL. 197

Plates: strains set up while flanging, to avoid these they
should be finished fairly hot or annealed.

Sheets: Blackplates and Tinplates. annealing may be carried
to excess : streaks, roughness, indentations these are due to foreign
substances rolled in : certain kinds are never due to the steel maker.

Strips for stamping and cold rolling should be finished fairly hot,
or, better, annealed.

Strips for welding should be rolled at low temperatures.

Hoops: these have a tendency to overheat when getting down
to thin sections.

Wire Rods and Plain Wire: avoid hardness by cooling slowly
in masses, and avoid chilling locally by cold objects; the tendency
is to draw through extra passes without annealing.

Galvanised Wire: brittleness is sometimes induced, especially
in the larger sizes.

Pickling Hardness: this is due to hydrogen, and may be re-
moved by heating: pickling blisters are distinctive from other
kinds, which are essentially the fault of the steel makers, and not
that of the steel.

Galvanising is generally recognised as tending to make articles
brittle.

Cold Drawing or Rolling: this has a very marked hardening
effect, sometimes producing great brittleness. Material for this
should be as soft as possible, preferably annealed.

SECTION VI.

The required standard tests are discussed, and a table is given
showing the types of faults and their manifestations, by whom
originated, their probable cause; and tests for identifying the causes.



The following members took part in the Discussion : Mr. J. E.
Stead, Mr. Andrew M'William, Mr. T. Vaughan Hughes and the
Chairman.

The author replied, and a vote of thanks was accorded to him.

I .'-'."



COPPER AND IRON ALLOYS."
Paper by J. E. STEAD.



Abstract.

AFTER briefly reviewing the contradictory evidence in metallurgical
text-books, and showing the need of further research on the subject,
the author described the nature of his recent work, which may be
briefly summarised as follows :

1. That copper and iron alloy most readily by direct fusion in
all proportions.

2. That they may be classed into three main sections :

(a) Alloys containing from traces to 2.73 per cent, iron and

97.2 per cent, copper.

(b) Alloys containing from traces to about 8 per cent, copper

and 91.5 per cent. iron.

(c) Alloys intermediate between a and b.

The alloys of (a) and (b) sections are practically homogeneous,
(a) consisting of copper with iron in solid solution, and (b) consisting
of iron with copper in solid solution.

(c) The alloys of this section apparently contain saturated solid
solutions, copper in iron, and iron in copper, separate from each
other, but in micro-juxtaposition.

The evidence is conclusive that in solidifying the alloys of section
(c), the portion first to fall out of solution is the iron containing
copper in solid solution.

The author discusses the effect of carbon, and showed that in
the alloys containing more than 7.5 per cent, copper, on heating
to whiteness with charcoal, copper containing about 10 per cent,
iron is thrown out of solution, and falls to the bottom, leaving a
layer of carburised iron on the surface, containing about 7.5 per
cent, copper. In conclusion, he points out that the conflicting
evidence referred to in the paper was most probably due to the fact
that some of the experimenters in the past had not taken the pre-
caution to use iron free from carbon in their experiments. He did
not consider that, the alloys of copper and iron were of industrial
value.



The Discussion was combined with that on the paper by Messrs.
Stead and Wigham (see page 199).

A vote of thanks was accorded to the author.



THE INFLUENCE OF COPPER ON STEEL FOR WIRE-
MAKING."

Paper by J. . STEAD and F. H. WIGHAM.



Abstract.

THE authors describe experiments on a series of steels with and
without copper, prepared by dividing the finished steel in each
series, when in a fluid state, into two parts, to one part of which
copper was added. The amount of copper added to the steel
varied between 0.46 per cent, and 2.00 per cent. Four of the
series were made by the Bessemer process, and one by melting in
a crucible, in Sheffield. The mechanical properties of the steels
are given in tabular form, showing the tenacity, bending and other
properties, after each pass through the draw plates. The con-
clusion the authors arrive at is that the copper in such large
quantities as they experimented with does not improve the quality
of the wire, but generally has a deteriorating influence, particularly
in the presence of high carbon. The only apparently good property
cupreous steel wire possesses is that it is not so readily corroded as
the non-cupreous material. In conclusion, the authors point out
that it is desirable that further experiments should be made with
smaller .quantities of copper than 0.5 per cent, to ascertain w-hat
quantity is admissable without disadvantage.



The Discussion on the two papers by Mr. Stead and Messrs.
Stead and Wigham was opened by Mr. Samuel Lloyd, and con-
tinued by Mr. Thomas Turner, Mr. T. Vaughan Hughes, Mr. Axel
Wahlberg, Mr. A. J. Atkinson, Mr. A. M'William, and Mr. Frank
Hill (by correspondence).

The authors replied, and a vote of thanks was accorded to them.



THE PRESENCE OF CALCIUM IN HIGH GRADE
FERRO-SILICON."

Paper by G. WATSON GRAY.



Abstract.

HIGH grade ferro-alloys of late years, especially those produced
in the electric furnace, have presented many interesting points to
the metallurgical chemist, and, at the same time, some troublesome
ones to the analyst. Having recently come across ferro-silicon
containing calcium, and not having noticed this element recorded
before in a ferro-alloy, the author submits this paper, so that its
presence may be noted by users, and its good or ill effect on the
steel observed.

He has, for some time past, noticed the presence cf magnesium
and aluminium in ferro-chromes, but calcium has bsn absent.
The presence of magnesium and aluminium is not to be wondered
at, seeing that chrome ores contain these elements in large
amounts, and that the reduction of the chrome ore is brought about
in the electric furnace. The same, to some extent, may be expected
with ferro-silicon, as no doubt calcium compounds constitute a large
proportion of the flux. High grade ferro-silicon containing only a
very small percentage of calcium can be made in the electric
furnace, and if the presence of a large percentage of calcium is
objectionable, the makers will have to arrange accordingly. He
is, however, inclined to think the calcium will be beneficial, but
this is a matter for practical trial by the users.

While the calcium may be looked upon as a special feature of
some makes of high grade ferro-silicon, many of the other im-
purities, such as chromium, nickel, tungsten, are purely accidental,
resulting from the remains of previous charges of ferro-alloys not
being completely removed from the furnace. Their estimation,
however, cannot always be neglected.

The author gives analyses of ferro-silicons containing 0.79, 3.29,
7.12, 6.96, 14.40, and 2.32 per cent, of silicon; and describes a
new method for conducting the analysis.



Mr. T. Vaughan Hughes took part in the Discussion, and the
author replied.

A vote of thanks was accorded to the author.



THE PROFITABLE UTILISATION OF POWER FROM
BLAST-FURNACE GASES."

Paper by B. H. THWAITE.



Abstract.

THE author explains that the results of his researches into the
subject of fuel waste in our iron and steel works, on which he
contributed a paper to the Iron and Steel Institute in the year 1892,
culminated in his invention of utilising the waste effluent gases of
blast furnaces in internal combustion engines; and that this inven-
tion, he further explains, has made the blast furnace a source of
power, rivalling even that from waterfalls. It is further demon-
strated that, owing to the blast furnaces being generally located
in the centres of industrial areas, this source possesses advantages
for the production of electrical power, both for industrial uses and
for transmission purposes, not possessed by the waterfalls. The
author explains that one of the results following the use of blast
furnace gas for the direct production of power in internal com-
bustion engines, has been a marked progress in the mechanical
perfection of power capacities, and the thermp-dynamic efficiency
of such engines. As high an efficiency as 30 per cent, has been
obtained, and one of 25 per cent, should always be obtainable, and
the power capacity of these engines is now no more limited than
that of the steam engine.

The author describes his new scheme for obtaining all the power
possible from the blast furnace. This includes the recovery of the
sensible heat that is otherwise lost in cooling the blast furnace
gases, for heating the air to gasify common coal in producers, and
also to support the combustion of the gases thus produced in hot
blast stoves, instead of employing the dirty, but, when cleaned, ideal
power gas effluent from the blast furnace. This latter gas is in the
author's system entirely diverted for the production of power. The
hot blast stove efficiency is due to the positive supply of air
and gas under pressure, which makes the combustion independent
of the vagaries of the chimney draught. The higher thermal
value of coal producer gas when burnt in fire brick chambers
ensures a higher temperature of the stoves, and this in addition to
the higher thermal recuperative efficiency due to the absence
of lime dust; all of which advantages secure an efficiency such as
cannot be expected from the present system, and react beneficially
on the furnace. The author enters into an explanation of the
reasons why hot blast stoves are so thermally inefficient, because

15



202 UTILISATION OF POWER FROM BLAST-FURNACE GASES.

of the effect of the lime dust deposited on the brick surfaces, lime
having only one-fifth the thermal conductivity of a brick that is
absolutely clean. In the new system, the brickwork of the stoves
will always be in the best condition for conducting heat.

The power potential of a blast furnace, when the new system is
applied, is estimated as being equal to an output electrically trans-
formed as follows for a furnace having an output capacity of 100
tons per diem :

CASE A. Kilowatts

I.H.P. Elec. H. P. reduced by

25 percent.

All the thermal value of blast furnace
gas except that required for steam blow-
ing engines is utilised for developing
power in internal combustion engines,
the hot blast stoves being fired with
producer gas ... ... ... ... 3253 2602 1456

CASE B.

All the thermal value of blast furnace
gas, including that required to develop
the power for blowing, pumping, and
hoisting purposes, is utilised for de-
veloping power in internal combustion
engines, the hot blast stoves being
fifed with producer .gas ... ... 5093 4074 2280

i The following are the characteristics of the furnace having the
foregoing power output potential :

Air blast pressure, 10 Ibs. 0.67 atm.

( CO =24 p.c.

Combustible percentage of effluent gas, 28 p.c. < H = 2 p.c.

/CH 4 = 2 pc.

f N =60 p.c.
Combustible percentage or inert gas, 72 per cent. < QQ __

'Ratio CO 2 to CO = i to 2.

Fuel consumption per ton of pig iron = 900 kilos.

The author demonstrates why the blast furnace gas is almost
ideal for producing power; he further points out that, seeing this
gas flows from the furnace to the gas engine, as does water to a
turbine, the labour associate of the dangerous steam boiler is not
required. It is calculated that it will be possible, when the new
system is applied throughout the year of 8000 hours, to develop
on kw. hour at a cost of o.i5d., so that there is a margin of a
Satisfactory profit for the ironmaster without destroying the ex-
ceptional cheapness of the power. The author's system, in which
all the blast furnace gas is available for power production, also



UTILISATION OF POWER FROM BLAST-FURNACE GASES. 20$

provides an auxiliary power producing plant, so that when the blast
furnace is blown out for any reason, the gas from the producing
plant is diverted through the cleaning plant to the gas engine, coke
fuel being substituted for slack coal, so there is no interruption
in the continuity of the power-producing operation.

The author described the various outlets for electrical power
that could be generated by the new system, including that involved
in satisfying the internal requirements of an iron and steel works,
and also for providing the electric energy to permit the remarkable
series of electro-chemical and electro-metallurgical industries to be
profitably operated. He demonstrates the peculiar advantages
possessed by an iron works for carrying on these industries. He
instances the production of silicon and calcium carbides, and the
production of the metals chrome, nickel, and aluminium, which
are exceptionally suitable as associated industries for an iron works.
The principal electro-chemical and electro-metallurgical processes
that have been developed during these last few years are briefly
explained. Inter alia, he points out that some of the new carbides
may be employed in the steel converter in place of the alloys, ferro-
manganese and spiegeleisen. The increasing use of metallic
chrome, silicon, and other .metals to alloy with iron or steel em-
phasises the importance of the association of the industries pro-
ducing these metals with that of iron and steel making. The
importance of the new power system, as a profit making auxiliary
to that of iron making, is emphasised, and especially the fact that
the blast furnace being situated in the centre of many of our staple
industries, gives the British ironmaster an advantage for the sale of
power or of the products from it.

The principal electrolytic processes are also described. It is
explained that when the blast furnaces are located within ten miles
of a salt deposit, it will be possible to produce economically the
alkaline products, such as those of sodium, caustic, and potash, as
well as the chlorates.

The- new system of power production, according to the author,
may, when fully developed, have an important bearing upon the
question of our being able to withstand a fierce onslaught of com-
petition from whatever quarter it may come.



Mr. Edward Theisen opened the Discussion, and the following
members also took part : Mr. T. Vaughan Hughes, Mr. A. W.
Richards, Mr. A. Greiner. Written contributions were also received
from Mr. F. W. Liirmann, Mr. Horace Allen and Mr. J. E. Dowson.

The author replied to the Discussion at the meeting and by cor-
respondence.

A vote of thanks was accorded to the author.



"AN INVESTIGATION OF THE SPECTRA OF FLAMES
AT DIFFERENT PERIODS DURING THE BASIC
BESSEMER BLOW."

Paper by W. N. HARTLEY and HUGH RAMAGE.



Abstract.

THE whole of this work is based upon several previous investigations
by one of the authors, published in the Philosophical Transactions
of the Royal Society for 1894, under the general title of "Flame
Spectra at High Temperatures " (Hartley). Results having
reference to the spectroscopic phenomena and thermo-chemistry
of the acid Bessemer process, as studied at the Crewe works of the
L. & N.W. Railway, have already been communicated to the Iron
and Steel Institute. The present communication deals with the
basic process as carried out at the North-Eastern Steel Works,
Middlesbrough.

General Statement of Results. Twenty-six plates were developed
with 140 spectra upon them, taken at intervals of one minute's
exposure throughout the different stages of the blow, by means of
a spectrograph designed for this purpose, which has been already
described in the " Journal of the Iron and Steel Institute." Photo-
graphs of the flames and fumes were secured by means of an
Anschiitz camera fitted with a Goertz lens. Observations were
rendered difficult owing to the large quantity of lime dust blown
into the air. The spectroscopic results are quite different from
those previously obtained. First, the continuous spectrum was.
much stronger, and appeared from the commencement of the blow ;.
secondly, the strong bands of manganese are absent or greatly
reduced in number and intensity; thirdly, many lines and bands
new to the Bessemer flame spectra were observed in addition to
the spectra of the alkali metals, iron, and manganese. Thus
rubidium, caesium, calcium, copper, silver, and gallium have been
identified. Very careful chemical analyses of the crude iron, the
ores, limestone, lime, slags, flue dust, and the finished steel were
made, and their constituent elements have been traced all through
the process of manufacture. The bases were in each case
separated and identified by spectroscopic examination.

While no indication was obtained of the amount of phosphorus.



AN INVESTIGATION OF THE SPECTRA OF FLAMES. 205

in the metal during the process of "blowing," some insight into
the chemistry of the process has been obtained. The greatest
interest, however, is attached to the knowledge it has given of
flame spectra under variations of temperature, and of the wide
distribution of many of the rarer elements in minute proportions
in ores and common minerals.

Description of the "J3low " and " Over-blow " in the Basic
Bessemer Process. The converter is first charged with about two
tons of lime in lumps, and then with twelve tons of fluid " mixer
metal," a mixture of metal coming direct from the blast furnace,
and molten pig iron from the cupolas. The blast is turned on,
and the vessel rotated into a nearly vertical position.

The blow may be divided into three stages. The first stage
ends when the flame drops, indicating that the carbon has been
burnt. The second stage ends when the vessel is turned down
for a sample of metal to be taken out and the slag poured off.
More lime is then added, and the blow is continued for a few seconds
longer to complete the removal of the phosphorus; this forms the
third stage. The average duration of the first stage was 12
minutes 20 seconds, and of the second stage 5^ minutes.

The blow began with the expulsion of a large quantity of lime
dust, which hid everything from view for a minute or two, and
covered the instrument and observers. A flame was visible at
the mouth of the converter as soon as the cloud of dust had
cleared away; this had a yellowish or yellowish-red colour. The
flame grew rapidly in length, and remained clear as in the acid
process until it dropped, and the second stage began. In this
stage the flame was very short, and a large quantity of fume was
expelled from the vessel; the flame grew longer, and the quantity
of the "fume increased as the blow proceeded. A plate of spectra
was usually taken by giving the same time of exposure to each
spectrum of the series until the flame dropped; two further ex-
posures were then made on the flame of the over-blow. The
spectra increases in intensity as the blow proceeds in the first stage,
and this can only result from a corresponding increase in the
temperature of the bath of metal and of the flame.

By the interference of the light reflected from a large quantity
of white dust and smoke, delicate detail was obtainable only by
working in the evening when the sun was very low, or after it had
set.

Considerable difficulty was experienced in the identification of
some of the lines and bands. The comparatively small disperson
in the less refrangible portion of the green and red rays caused
lines and the sharp edges of bands to be almost indistinguishable
on the strong continuous spectrum. In other cases, lines were
present which had not been observed in anv flame spectra before.



206 AN INVESTIGATION OF THE SPECTRA OF FLAMES.

CONCLUSIONS.

i. The phenomena of the " basic " Hessemer blow differ con-
siderably from those of the " acid " process. First, a flame is
visible from the commencement of blowing, or as soon as the cloud
of lime dust has dispersed. The authors conclude that the



Online LibraryInternational Engineering Congress (1901 : GlasgowReport of the proceedings and abstracts of the papers read → online text (page 18 of 37)