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International Engineering Congress (1901 : Glasgow.

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of coal.

With the exception of two firms who use from 10 to 25 per cent,
coke, all the Scotch furnaces now work with raw coal.

Blackband. The Lanarkshire blackband, which was discovered
in 1 80 1, has in 1901 been practically exhausted, as there are now
no pits in the Lanarkshire coalfield working it as a principal pro-
duct, though a small quantity of a thin blackband is raised with
the gas coal at one or two pits. Some blackband of excellent
quality is, however, still raised in Fife and Midlothian for smelting
in the Lanarkshire furnaces, whilst the somewhat leaner black-
bands of Ayrshire are still fairly plentiful.

Clayband. From somewhat different causes the use of clayband
ores has also declined greatly, and these are now but little worked,
except in cases where they can be worked with a coal seam. The
greatly increased cost of mining labour is partly responsible for
this, whilst the greater attention paid to sampling and chemical
analysis since haematite smelting became general has shown the
necessity of abandoning many places working poor ores.

Other Ores. So far as I can learn, no iron ore is at present
worked in Scotland except the bedded claybands and blackbands
of the carboniferous system, though several small vein deposits
of haematite are know to* exist in the older rocks, and com-
paratively small quantities have been worked from time to time;
consequently the importation of foreign ores, which was almost

* G. A. Mitchell, Presidential Address to Mining Institute of Scotland,
1894. J. A. Longden, Presidential Address, Institution of Mining Engineers,
London, 1899.



IRON AND STEEL INDUSTRIES OF THE WEST OF SCOTLAND. 175

unknown twenty years ago. has been steadily growing year by
year, from 42,471 tons in 1879 to 1,403.889 in 1899, the last
year for which the Government statistics are as yet issued.
With this new state of affairs, however, Scotch ironmasters have
not abandoned their traditional policy of controlling their raw
materials, and three of the largest firms now own or control
mines in Spain which are believed to be capable of supplying their
requirements of haematite for many years to come.

Preparation of Ores. The extreme difficulty of maintaining
regular working* of furnaces supplied with soft coal and small
and inferior ores has of late years caused considerable attention
to be given to the briquetting of small ores. Several years ago
Mr. G. Fisher, then manager of the Shotts Works, devised and
patented a plant for working up the small dust from blackband
into briquettes for the furnace, a little yellow clay being used as
the agglomerant, and this is still working successfully. Since
then several plants have been put down for the manufacture of
briquettes from purple ores, clay or Irish aluminous ore being
added as agglomerant. In the present year the Coltness Com-
pany have put up a large plant for screening the small ores from
the Alquife mines, of which they are the principal owners, and
moulding the finest smalls into briquettes, the machine used being
a modification of the well-known Yeadon coal briquette machine,
suitably strengthened.

Blast Furnace Equipment and Practice. At the present time there
is a greater uniformity in both dimensions and output of the
furnaces at different works in Scotland than in any other district.
In 1872 the average make per furnace per week was 165 tons,
with a consumption of 2.95 tons of coal per ton of pig. In 1884
the production had increased to 200 tons, and the coal been
reduced to 2.20 tons. In 1899 the production had increased to
270 tons, and the coal consumption decreased to 1.83 tons. Last
year the average weekly production had decreased to 265 tons.
The coal consumed per ton is not yet officially published, but will
show a fractional increase poorer results due entirely to the
inferior quality of coal and ores used.*

To those accustomed to the hard driving of some recently con-
structed coke furnaces these makes will appear extremely small;
it should not, however, be too hastily concluded that the pro-
prietors and their managers are ignorant of their business. A
furnace working on splint coal has to combine in itself a coke
oven and a blast-furnace, and if it is driven so fast that any of the
coal reaches the zone of fusion without having its 35 or 40 per

* "Thirty-sixth Annual Report, Alkali, etc., Acts, p. 170; also, "Thirty-
seventh Report," p. 138.



176 IRON AND STEEL INDUSTRIES OF THE WEST OF SCOTLAND,

cent, of water and volatile hydrocarbons expelled, the temperature
there is so reduced as to completely disorganise the working. An
obvious remedy would appear to be an increase in the height of
the furnaces, -and this was tried, and gave very good results so
long as uniformly hard coal was used; but with an admixture of
softer coals the crushing was too great, and many of the heightened
furnaces have now been reduced to a height of 60 to 65 feet, which
is the average height in Scotland. Of the many attempts made in
the last few years to increase the rapidity of driving, one of the
most encouraging was recently made at Clyde Ironworks, about
which Mr. T. B. Rogerson writes me as follows : " I cannot say
much about our hard driving at Clyde, as we were on too short a
time to make much comment; but this I can say, that we blew
one furnace for three weeks with 8J Ibs, blast, and made about 90
tons a day of good iron. We had to' stop this hard driving because
of scarcity of water, and our stove power not being sufficient for
all furnaces, but intend at some future date to again go on with it.
We used nothing but splint coal during this trial."

As almost all the Scotch works are now equipped with by-product
plants, the manager has to work with one eye on this department,
and anything which tends to produce irregular driving in the
furnace is very quickly reflected in the returns from the chemical
department.

In one respect the value of an increased number of tuyeres
Scotch practice has anticipated the conclusions of modern
designers. For many years past eight or nine tuyeres have been
the rule in Scotland, and in the last few years several have been
built with twelve.

All the works in Scotland are now fitted with a full equipment of
firebrick stoves, and fairly high temperatures (1200? to 1400$ F.)
are the rule. The stove which has found most favour is the
Ford and Moncur nine or ten out of the sixteen working plants
in Scotland being fitted with this type, and some of the stoves
have now been at work over ten years without any repairs other
than the renewal of hot-blast valves.

With the comparatively small makes in vogue there has been
no opening for blowing engines or charging machinery of the
American type, but pig lifting and breaking machinery has been
introduced at Messrs. Dixon's two works, Govan and Calder, and is
giving complete satisfaction.

BY-PRODUCTS.

In 1885 the recovery of tar and ammonia from the blast-
furnace was an infant industry just emerging from the region of
small scale experiment. At the present time, with one exception,



IRON AND STEEL INDUSTRIES OF THE WEST OF SCOTLAND. 177

every works in Scotland either has a complete by-product plant or
is erecting one, and all the earlier plants have been considerably
enlarged and improved. In all the recent improvements the
changes have been in the direction of simplicity of construction
and safety in working; the size of the gas tubing has been
increased ,and obstructions in the shape of sharp bends, etc.,
have as far as possible been avoided. The waiter coolers and
high scrubber towers of the earlier plants have been replaced by
the tar washer and horizontal liquor washer, which gives an
almost complete abstraction of ammonia. They require little atten-
tion to keep them in perfect working order for years. They have
the further advantage of holding only small quantities of gas in
each compartment, so that the danger of a serious gas explosion
is entirely eliminated. In designing these improvements, no one
has done more than Mr. A. GUlespie, of Glasgow, and the three
by-product works recently erected to his designs are admittedly
the " show " plants of the country. As an example of the newest
work in this direction, the following brief description of the new
ammonia works at the Summerlee and Mossend Company a"t
Coatbridge, for which I am indebted to Mr. Gillespie, will be of
interest :

Summerlee New Ammonia Plant. " The Summerlee plant con-
sists of seven furnaces, of which five or six are usually in blast
at once. The gas from all the furnaces, having a temperature
of 300 deg. Fah., or a little over, is first taken by a tube of 9 feet
diameter to the tar washer (or primary washer), a horizontal
vessel 64 feet long and 16 feet wide, in which the gas is split up
and made to pass in thin streams under diaphragm plates sealed
in tar. The hot gases are there brought into intimate contact
with the tar; the operation is twice repeated in the vessel to
ensure complete contact, with the result that the temperature is
reduced by about 130 deg. Fah., and the heavier tars contained in
the gas are entangled and thrown down, flowing slowly along the
sloping bottom of the washer to the regulating valve, where
they are automatically run off to the stock tank.

" The tar fed into the tar washer is the lighter tar from the
liquor washer and condensers, containing a large excess of en-
tangled water and gas; by the same operation these are expelled
and the tar heated and prepared for distillation in the tar stills.

" The partially cooled gases pass from the tar washer to the
air condensers, where they are .again split up and pass into
twelve boxes leading into a series of 2o-inch vertical tubes having
a total length of about 4^ miles. In passing through these the
temperature of the gases is brought down to about that of the
atmosphere, and they are in a fit state for the complete recovery



178 IRON AND STEEL INDUSTRIES OF THE WEST OF SCOTLAND.

of the ammonia in the form of liquor. The tar washer and
condensers are placed on the suction side of the exhauster, and
the first and second liquor washers on the discharge side.

" From the condensers the gas passes into the exhausters, of
which there are three sets, of the horizontal cylinder type, each
actuated by a pair of steam cylinders 18 inches diameter by 4 feet
6 inches stroke. The two gas cylinders are 6 feet diameter by the
same stroke, each pair of exhausters being capable of passing
915,000 cubic feet of gas per hour at thirty revolutions per minute,
or in all about 2| million cubic feet per hour.

"The two liquor washers are horizontal, 60 feet long by 12 feet
6 inches wide, in each of which the gas is repeatedly split up and
impelled under diaphragms sealed in liquor, the first washer being
fed with weak ammonia liquor, and the second with a small
quantity of pure water.

" The products recovered in the condensers and the liquor
washers pass into specially constructed separators, where, by the
difference in specific gravity, the heavy and light frothy tars are
each separated from the ammonia liquor. The washed gases are
returned fit for use in the furnace stoves, steam boilers, etc., etc.
The tar is dealt with in several tar stills, the oil distilled, graded,
and separated, and the pitch run out in bulk or in blocks.

" The sulphate plant is capable of manufacturing forty tons of
sulphate of ammonia per week, and the who'le plant is arranged as
far as possible to work automatically."

The amount of sulphate of ammonia recovered at the different
works varies from 20 to 25 Ibs. per ton of coal used in the fur-
naces, and the pitch and oil from 150 to 200 Ibs. the variations
depending largely on the nature of the coal used, as the amount
now lost in the gas at any of the works is extremely small.

Other By-Products.- Whilst our attention has been given to the
recovery of tar and ammonia, the possibility of utilising other by-
products of the blast furnace has not been entirely overlooked.
The suitability of the washed gas for gas engines was demonstrated
by the working of the gas engine at Wishaw the pioneer of its
class with the history of which most of you will be familiar.
That it has not as yet been followed by others is largely due to
the fact that all the power and most of the heating required about
the furnaces is already provided by the gas. For example, at one
works, in addition to' heating the blast furnace stoves and pro-
viding steam for the whole works, the gas serves to distil the tar
and ammonia, heat the core-stoves for three large foundries, distil
the coal for the gasworks supplying the village, etc., melt the steel
in a steel foundry; and the surplus is being applied to burn the
ore briquettes in a i2-chamber kiln. .



IRON AND STEEL INDUSTRIES OF THE WEST OF SCOTLAND. 179

Many attempts have been made to utilise the slag, but so far
the demand shows little prospect of overtaking the supply. Much
is used for railway ballast and for the foundations of roads, etc.,
and of late years considerable quantities have been used for
making mortar and concrete, with good results. Slag bricks of
excellent quality have been made experimentally, but, with the
present low price of bricks made from colliery waste, there does not
seem very much prospect of manufacture at a profit.

STATISTICS, ETC.

By the courtesy of Messrs. James Watson and Co., I am enabled
to bring up to date the table of stocks, shipments, etc., given in
Mr. Rowan's paper of 1885. From this it will be seen that the
output of the Scotch furnaces has been practically stationary,
whilst the shipments, and especially the foreign shipments, have
decreased. Side by side with this, there has been a gradual change
in the class of iron made. Up to 1885, the great bulk of
the furnace output was foundry and forge iron; in 1890 the make
of haematite had increased to 238,759 tons, against 498,307 tons of
ordinary and basic; in 1899 the hematite amounted to 581,534
tons, compared with 572,486 tons of ordinary iron; and at present
there are 43 furnaces making haematite, and only 36 working on
foundry and forge iron. As the haematite made is almost entirely
used in the Scotch steelworks, the decrease in pig iron shipments
means chiefly that we are exporting finished steel and steel ships
instead of crude pig iron.

In concluding this very hurried sketch of the present position
of the Scotch pig iron industry, I have to thank the proprietors
of the iron companies named, and Messrs. A. Gillespie and T. B.
Rogerson, for permission to publish information so freely supplied
to me.



180 IRON AND STEEL INDUSTRIES OF THE WEST OF SCOTLAND.

TABLE I.
Some NotaMe Dates in the History of fhe Scotch Pig-iron Trade.



About 1750

1760
1769

1779
1787
1788



1792



1801
j>

1802
1805
1828
1830



1833
1836

1837
1838

1845

1852

1879-80

1896



First charcoal blast-furnace in Argyleshire

built.

Carron Ironworks started.
Watt and Roebuck erected a steam engine

near Carron.

Wilsowntown Works commenced.
Omoa and Muirkirk Works commenced.
Clyde Works commenced. (In this year

there were eight furnaces at work in

Scotland. )
Devon Works commenced (with furnaces

cut out in the solid rock).
Glenbuck Works started.
Calder ,,

Balgonie (Fife) Works started.
Shotts ,, ,,

Monkland ,, ,,

Neilson hot-blast patent,
Gartsherrie Works started. (In this year

there were twenty-seven furnaces in

blast, and the year's production was

37,000 tons )

Dundyvan Works started.
Coltness ,, ,,

Summerlee ,, ,,

Carnbroe , , , ,

Gas collected and used at Dundyvan Works

from a sixty-five feet furnace.
Iron ore calcined with gas at Coltness.
By-product works started at Gartsherrie.
Gas-engine works with furnace gas at

Wishaw Ironworks.



Dismantled 1840-50.
(Omoa now dismantled)



Stopped 1858.
Now stopped.
Now stopped.
Now dismantled.



Now dismantled.



TABLE II.



Production of Sulphate of Ammonia from Scotch Blast- Furnaces (com-
piled from the Reports of the Chief Inspector of Alkali, &c., Works).



1883

1886
1887
1888
1889
1890
1891
1892

1893
1894

1895
1896
1897
1898
1899
1900



(First reported separately in 1886.)



about 400 Tons.



. - * .


3,75


. -


4,849


. . . - . -


- - 4,930


..


5,645


(Strike of Furnacemen)


- (4,564
- 15,790


......


10,500


(Colliers' Strike)


- (8,333
- 19,675


...


14,188





16,111


-


- 17,379
17, W



16,559



IRON AND STEEL INDUSTRIES OF THE WEST OF SCOTLAND. 181



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182 IRON AND STEEL INDUSTRIES OF THE WEST OF SCOTLAND.

II. MALLEABLE IRON.
By WILLIAM WYLIE.

The malleable or manufactured iron trade, which is sometimes
spoken of as if it were becoming almost a thing of the past, has
suffered less in Scotland than in most other districts. In the
three principal producing districts in Britain there has been very
little change during the last three years, due entirely to the
activity in the trade that has existed during that time; but com-
paring the output of twenty years ago with last year, we find the
production of puddled iron, as taken from the statistics of the
British Iron Trade Association, to be as follows, so far as particulars
have been supplied by manufacturers :

United South South

Kingdom. Staffordshire. Cleveland. Scotland. Wales.

Tons. Tons. Tons. Tons. Tons.

1882 - 2,841,534 660,326 852,199 210,300 213,179

1900 - 1,162,765 265,181 198,131 206,316 practically

none.

So that now the total production is only 41 per cent., South
Staffordshire 40 per cent., Cleveland 20 per cent, of what it was,
while Scotland has almost remained stationary during the whole
of that period.

The manufacture of malleable iron commenced in Scotland over
100 years ago at various small places, amongst them being Muir-
kirk Ironworks, erected in 1790, and which are still in existence;
but up to the middle of last century the trade was limited, and not
to be compared in extent with that of South Wales, South Stafford-
shire, or the North of England; from that time onwards, however,
new plants were laid down in rapid succession till about the year
1875, when the trade had reached its maximum.

By this time several of the older plants had been long since
cleared away, and several of the largest establishments, such as
Dundyvan Ironworks, Monkland Ironworks, Govan Bar Ironworks,
and, rather later, Glasgow Ironworks, St. Rollox, were dismantled,
and others, as Blochairn, Mossend, Parkhead, etc., converted into
steelworks. Within more recent years other places have been
established, as Waverley, Dundyvan (new), Woodside, and Victoria
Works (only two years ago), all in Coatbridge district, while the
Globe Ironworks have been transferred from Coatbridge to
Motherwell, and Coatbridge Works have been rebuilt on a new
site; many others have also been entirely remodelled. With these
additions and improvements on the existing plants, the productive
capacity, as has already been remarked, has remained constant.
At the present time there are employed in the manufacture of
malleable iron in Scotland 22 firms, owning 25 works, consisting



IRON AND STEEL INDUSTRIES OF THE WEST OF SCOTLAND. 183

of 396 puddling furnaces, 38 scrap furnaces, 17 bar mills, 23 guide
mills, 8 strip mills, 21 sheet mills, producing 325,000 tons per
.annum finished iron of all kinds (from particulars supplied by the
manufacturers). All the works, with one or two exceptions, are
situated in the Coatbridge and Motherwell districts of Lanarkshire.

No new process having been introduced in the manufacture of
puddled iron, the fundamental principles are just the same as have
been in operation or the last fifty years or more, so that the only
means of lowering the costs in order to meet the keen competition
of modern times is by adopting from time to time all the minor
improvements in furnaces and machinery, whereby the waste of
material and consumption of fuel is lessened, the output increased,
and thus the best results are obtained from the plant, and the
general wages and charges are reduced. In this respect the
various works have not been slow in adopting any means which
they considered would be a benefit to them in their respective
branches.

A quarter of a century or so ago any one passing through an
iron-producing district used to be struck with the long tongues of
fire from the blast furnaces, and the intermittent flames emitted
from the innumerable stalks of puddling and mill furnaces. Now
all this is changed ; the former have all closed tops, the gases being
used to heat the stoves and for raising steam, and there are few
stalk furnaces to be seen in malleable works. The country around
is now dark in comparison, the only light being the flash from the
opening doors or the glow from metal on pig beds and when being
conveyed to hammer or rolls, the blast-furnaces even requiring to
be lit by electricity.

Puddling furnaces are rather larger than formerly, working
heavier heats and more per shift, and all have closed grates with
forced blast underneath in order to consume smaller fuels, and
have boilers attached to utilise the waste heat for steam raising.
The same may be said of mill furnaces; most in this district are
ordinary coal furnaces, with boilers overhead or at end ; gas furnaces
have not been widely adopted in iron mills here. By. making
these of larger capacity, and devoting every attention to their con-
struction, also by using the best types of high-speed engines and
improvements about the rolls, the output of mills has been largely
increased during recent years, so that it is no uncommon occurrence
to have 1 2-inch guide-mills heating in two furnaces and rolling 30
to 40 tons of iron piles per turn of twelve hours, which is quite
equal to the best practice of any district even of our American
cousins in the same class of work.

A ^ very varied class of trade is conducted in the iron mills in the
district, both as regards the qualities and descriptions of material
produced.



184 IRON AND STEEL INDUSTRIES OF THE WEST OF SCOTLAND.

Best Scotch iron commands a high reputation, and all qualities
are manufactured, from the common unmarked bars for the export
market to the highest grades that can be produced; and, situated
as all the works are within a short distance from Glasgow and the
Clyde shipyards, where there is a concentration of all the allied
industries shipbuilding, marine engineering, boiler making, loco-
motive building, pipe and general founding, machine tool and
general engineering, and fence, bridge, and roof building there is
a steady and large outlet for all sizes and descriptions of bars, ship
and boiler plates, hoops, sheets, and sectional iron of all kinds.

Coatbridge may also be said to be the chief seat in the kingdom
of the welded tube industry, so that there and in and around
Glasgow there is a large demand for strips and tube hoops.

As a metallurgical centre the Scotch ironworks are, therefore,
most favourably situated, having the great natural advantage of
being within easy access of a seaport, as well as being in the midst
of a perfect hive of allied industries.

It may here be said that for many years the wages of the
employees of the malleable iron trade in Scotland were regulated



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