February 2, 191'7.

THE COLLIERY GUARDIAN.

239

SOUTH WALES INSTITUTE OF
ENGINEERS.

A /general meeting of the South "Wales Institute of
Engineers was held.at Cardiff on Friday, January 26.

The retiring president, Mr. William Stewart,
announced that the council had elected, as president of
the institute for 1917-18, Mr. H. Bramwell— a gentle-
man who occupied a leading position in the South Wales
coal field and among the mining engineers of the
country;

The new president having taken the chair,

Mr. T. H. Deakin moved a vote of thanks to the out-
going president. He said they had had a succession of
presidents, from Mr. Menelaus in 1857, which saw the
inauguration of the institute, who had contributed in
no small measure to the remarkable industrial develop-
ment of South Wales. Mr. Stewart was a representa-
tive type of those able and far-seeing men. He had
always manifested the keenest interest in the institute,
and during his presidential term had not missed a single
meeting, either special or general.

Mr. H. T. Wales seconded the proposition of thanks
to Mr. Stewart, who, he said, was to be congratulated
upon a highly successful year of office.

Mr. Stewart, acknowledging the resolution, expressed
appreciation of the assistance and co-operation he had
received from the council and the secretary, Mr. Martin
Price.

Election of Office Bearers.

The following were elected to fill vacancies occasioned
by the retiring office bearers :—Vice-presidents : Mr.
Edward DawsOn, Cardiff; Mr. William Johnson, Bridg-
end. Members of council : Mr. Theodore Vachell, New-
port; Mr. W. W. Hood, Chepstow; Mr. Leonard W.
Llewelyn, Newport; Mr. Hubert Spence Thomas,
Cardiff; Mr. A. 0. Schenk, Swansea; Prof. Frederick
Bacon, Cardiff; and Mr. Geo. Hann, Aberdare.

New Members.

The President -also announced that the following
candidates for admission to the institute had been
elected :—Messrs. B. E. Blackledge, Cross Keys, Mon.;
W. Donald, Glasgow; David Evans, Blackwood, Mon.:
H. W. G. Halbaum, Cardiff; Harold Jeans, London;
A. C. Macwhirter, Cardiff; C. G. M. New, Cardiff;
W. Rees, H.M.I.M., Cardiff; and D. S. Thomas,
Pengam, Mon.

Raising Coal from Vertical Shafts : Presidential Address.

The subject of the President’s inaugural address was
the raising of coal from vertical shafts. He said it was
interesting to note that many things that were perhaps
regarded by them as comparatively recent innovations
had been proposed and used, under different conditions,
in the-past. For example, conical drums were patented
in 1772, and used with horse gins. It was also interest-
ing to note the rise and decline in the use of various
appliances and ’arrangements, depending, no doubt, on
the state of mechanical knowledge and of craftsmanship
at the time. Basket corves were used in early times, and
generally abandoned about 1850, but their use continued
at the comparatively important William pit, White-
haven, until 1871. Similarly, an automatic appliance
for cutting off steam and applying the brake to prevent
overwinding was introduced at Glodwick Colliery,
in Lancashire, in 1839, but it had only recently been
generally applied as the result of legislation, and then
only with many doubts. With regard to weight versus
speed, there had been a continued struggle to enlarge
the capacity of the winding plant, which had been
achieved sometimes by increased speed, and sometimes
by increasing the load. The introduction of the single-
cylinder engine was a reversion at the time to slow speed
with heavy load, and its work, in subsequent years,
measured in pounds of steam used per load lifted, had
only been excelled by some of the quite recent machines
of a different type.

Up to about 1870 great stress had been laid by mining
engineers on the statical balancing of the ropes in deep
mines. At that time balancing the ropes was almost
invariably done by means of balance chains working on
the drum shafts, and dropping into shallow staple pits.
The method was easily and advantageously applied to
the vertical winder with flat ropes; and, prior to the
conical drum coming into favour, it Was applied to some
double horizontal engines with round rope drums.. The
Silksworth No. 2 pit engine, erected in 1872, or there-
abouts, was probably the most highly-developed of this
type. About 1874 the balance chain, method gave place
to the tail-rope balance, in the shaft, or to the conical
drum. With the increasing depths, and the large out-
puts required, the conical drum soon reached a culmi-
nating point. To obtain rope-holding capacity with the
necessary strength, the size and weight of such drums
became very great, and it was probable that in some
examples the improvements in the design and steam
economy of the engine itself were more or less cancelled
by the weight and size of the drum, resulting in no all-
round economic improvement. The introduction of the
cylindro-conical drum about 1905 helped to meet this
difficulty (as to the size of drum), but it had another
object ns well. Its principle was that the angular
acceleration of the masses was completed and full speed
attained with the two ropes on the maximum and mini-
mum diameters respectively. Its introduction into the
South Wales coal field was largely due to the initiation
of Mr. E. M. Hann, of the Powell Duffryn Company.
The conical portion of the drum, carrying only three or
four coils, merely acted as a transfer from maximum, to
minimum diameters, which, under ideal but impossible
conditions, should be effected instantaneously at a jump.
With deep shafts and large ropes, drums must have con-
siderable rope-carrying capacity. This could only be

attained by increased size, either in diameter or in
width, or by re-coiling the rope on itself in layers. Cir-
cumstances generally limited the width of the drum.
Sites were restricted in size, excessive lateral angling
caused undue rope wear, and ropes swagged if the drum
were placed at too great a distance from the pulley.
Having exhausted the practical width of the drum, capa-
city must be sought on the diameter; hence the trouble
as to weight and size.

In a paper submitted to the South Wales Institute of
Engineers in 1914, he brought this phase of the subject
before them. He then advocated, in order to keep down
the size of the drum, the re-coiling of the round rope
upon itself, as being preferable to excessive lateral
angling. In that, paper, profile sections were given of
two drums, then under construction, each to carry some
850 yds. of comparatively large rope, the one drum 12 ft.
in diameter, and the other 12 ft. and 18 ft. in diameter.
To carry these ropes without re-coiling, and within a
reasonable lateral angle of spread, would have entailed
drums of 24 ft. and 34 ft. diameter, instead of the 12 ft.
and 18 ft. with re-coiling. Some experience of the prac-
tice of re-coiling was given in that paper, and further
experience had since been obtained which might now be
given. On a 15 ft. diameter drum taking 14 in. diameter
ropes (re-coiling), and raising a 10-ton gross load from
400 yds.-, seven ropes had 'been used. Their average life
had been 26 months 16 days, and 295,385 tons of coal
had been raised per rope, in addition to rubbish, etc.;
and the cost of the rope per ton of coal raised 'averaged
0’0849d. One rope failed after a life of 19 months 16
days, and this brought down the average. The maxi-
mum-life of any one rope had been 36 months 1 day.
Having regal’d to the usual conditions of a Welsh shaft
(wet and dirt), these figures tended to show that re-coil-
ing might be properly practised, if and when other
reasons made it desirable. In the other instance, the
ropes re-coiled satisfactorily. The engine (two 28 in.
diameter cylinders, 5 ft. stroke, 1501b. steam pressure,
with variable expansion) at present raised three tons of
coal in two trams from 750 yds. at a maximum speed of
40 ft. per second without a counter-balance rope. Full
speed was. reached on three revolutions. There W’as no
doubt that, with a counter-balance rope, as intended,
it would raise with equal facility the designed load of
six tons of coal on. four trams.

Single v. ^Compound Engines.

He had made reference to the improvement in the
two-cylinder horizontal type of winding engines. In
order to take advantage of the economy obtainable- by
the use of high-pressure steam (1501b. per sq. in., or
thereabouts), engineers began to introduce compound
winding engines in 1888. The adoption of this type,
with two or four cylinders, had not perhaps been alto-
gether general, as with improved expansion gears and
stronger general design it might be open to doubt, in
the case of winding engines, whether equal all-round
economy and reliability might not be obtainable without-
compounding. The comparatively recent introduction
of the low-pressure turbine (using the winding engine
exhaust, and therefore in itself constituting a low-pres-
sure cylinder) would probably render the adoption of
compound cylinders in the winder still less likely of
general adoption. It might be mentioned, in this con-
nection, that the heat accumulators for bridging over the
intermittent nature of the winder exhaust, which were
primarily introduced by Rateau and others, were
apparently giving place with advantage to volume accu-
mulators of the gas holder type. In the pure heat cycle
the heat accumulator was the more efficient appliance,
but in practical working the heat accumulator involved
a certain back pressure in the engine cylinders, which
adversely affected the all-round, economy; whilst the
volume accumulator worked practically without back
pressure, and although not to any material extent accu-
mulating heat, it was perhaps, on the whole, the more
desirable apparatus.

The speaker compared five more or less representative
types of winding plants. In these particulars, he
said, it would be seen that the struggle between load and
speed was brought into view. The inference he drew
was that speed was controlled by wear and tear of the
plants, and possibly by safety; whilst the load was
chiefly controlled by the improvements in rope construc-
tion. Incidentally, it might also be noted that, with
slow speed, cages might properly be very much lighter
than with high speed, and therefore the proportion of
effective load (coal) was materially improved. It might
further be pointed out in this connection that the life
of ia rope was mainly in relation to the number of winds
it made; 'and provided it was of reasonably adequate
strength as compared with the load, its life was not so
much influenced by the actual weight lifted each wind.
Doubling the load halved the number of winds, and this,
with the reduced speed, must largely favour rope con-
ditions.

Now, what deductions might be drawn from his his-
torical review? He thought it might be summarised in
the statement that, in winding, a heavy load paid better
than high speed, provided this was not attained at the
cost of an unreasonably heavy initial outlay. Accepting
that position, what development is probable? His own
opinion was that for depths of 3,000ft., which they were
now approaching in practice, development might pro-
perly tend towards an equipment on the lines of a hotel
or warehouse lift. The present single rope to each cage,
which both suspended and actuated the load, might be
replaced by a. suspending rope common to the two cages
worked over a pulley on the headgear, with subsidiary
operating ropes to each cage from the-winding drum. The
former rope would thus suspend the load, and would be
relieved of all acceleration and retardation strains. The
actuating ropes, on the other hand, would be relieved of
the suspended weights, and their work would consist of
accelerating and retarding the masses only. Such an
arrangement would greatly diminish the size necessary

for the 'actuating ropes, with a cor responding reduction
in the size and weight or the drum and engine equip-
ment, and would put the necessity for stage winding still
further into the background. Such an arrangement was
in some respects similar to the Koepe system, which,
all though well known, had not been adopted to any large
extent in this country. The difference lay in the separa-
tion of the suspending and actuating ropes. It, how-
ever, shared with the Koepe arrangement the drawback
that had chiefly been responsible for the latter’s lack of
popularity in this country, viz., the rope could not be
re-capped. There was no spare rope on the drum to
enable the rope to be cut and re-capped, and it was the
cap end of the winding rope, largely in the cap itself,
where trouble and failure were to be expected.

Mr. W. D. "Wight, in moving a vote of thanks to the
president for his address, said the president and he were
colleagues some 35 years ago, receiving mining instruc-
tion under Mr. John. Dalglish, who assisted the- late Mr.
J. J. Atkinson, father of the chief inspector of mines
in South Wales, in nearly all his most valuable experi-
ments, which enabled him to write a standard work on
mines ventilation.

Dr. H. K. Jordan seconded the resolution of thanks,
which was cordially adopted.

Mr. H. Spence Thomas followed with , a paper on
“ Improved Tinplate-Making Machinery,’’ upon which a
discussion was opened and adjourned to the next meet-
ing of the institute, at Swansea, on March 27.

COKE OVEN MANAGERS* ASSOCIATION.

A well-attended meeting of the Midland section of the
Coke Oven Managers’ Association was held at the
University of Sheffield on Saturday,, January 27, at
which Prof. W. G. Fearnsides, Sorby Professor of
Geology in the University, delivered a lecture on “ Some
Physical Properties of the Two Chief Mineral Consti-
tuents of Coke Oven Bricks.’’

Mr. G. Chrisp (president) occupied * the chair, and,
in opening the'meeting, said the subject of the lecture
was one in which they were vitally interested, and of
which, he wa.s afraid, they did not know a great deal.
Bricks were a source of great trouble. The different
constituents did not suit every class of coal alike. They
had some coals which were salty, and some which were
not. Some coke oven bricks had to stand much higher
temperatures than others, so that they got varying con-
ditions with varying bricks, and exactly what class of
brick would suit the greatest number of coke oven people
was not quite known. The lecture that night was to be
the first of a series; and Prof. Fearnsides would deal
later on with the salt question, the effects of tempera-
ture, and so forth. The president announced that at
the next meeting of the section, on February 24, Mr.
J. W. Lee would read a paper on “ The Scientific Con-
trol of a By-Product Coke Oven Plant.’’ The meeting
would probably be held at the Grand Hotel, Sheffield, as
being a more central place. He urged the members to
attend the annual dinner of the section, at which the
chief guest would be Lord Moulton, Director-General of
Explosive Supplies, ia department of the Ministry of
Munitions which was intimately connected with their
work. He was ’afraid, that there was a very stormy
period ahead for the coke oven industry. He was very
thankful that they had formed an association to look
after their interests, and was sufficiently optimistic to
believe that out of the sea of trouble they would emerge
invigorated and .strengthened, -and that they would
flourish, provided they had the support of the members',
and that the council worked sufficiently hard and
earnestly, as he believed they would.

Properties of Refractory Materials.

Prof. W. G. Fearnsides then read his paper, "“ On
Some Physical Properties of the Two Chief Mineral
Constaituenits of Coke Oven Bricks.” (See page 223.)

DISCUSSION.

The President, in opening the discussion, said they
could easily see, from what they had been told, how
unreasonable it was for them to expect uniform results
in their coke ovens as regarded the linings. He had
come across some peculiar instances cf what he thought
was tridymitisation. He knew a coke oven brick which
was a very excellent one in some respects. It would stand
a tremendous temperature; there was no shrinkage, no
growth; but, as soon as it was cooled down, if they even
looked at it it would break into a thousand pieces. He
had always been puzzled to know the reason of this.
The difficulty had not occurred with bricks from Stour-
bridge, or from the Halifax region.. In a company like
that, it would not be fair to say where the brick came
from.

Mr. B. "W. Haigh (Barnsley Main), in moving a vote
of thanks to the lecturer, said one of the things that they,,
as an association, had to congratulate themselves upon
was the fact that.they had become, in any sense con-
nected with the University of Sheffield. He little
thought, when they set out as an association, that they
would ever have papers which would set their thoughts
running on such (to him) quite new lines as that to
which they had listened. They had certainly had some-
thing given to them to think about, and they would go
away with a very much enhanced respect for academic
and scientific knowledge. They had sometimes been
rather inclined to regard these things as pure theory,
and not very much connected with .practice. The war
had certainly done them one good turn in causing Prof.
Fearnsides to turn his thoughts, not to pure science only,
but to practical problems, as he evidently had been
doing. It was no small matter to have their attention
drawn to the excellent American publications to which