1064

THE COLLIERY GUARDIAN.

May 15, 1914.

it is of the Sentinel double-stage type, and has three pairs
of cylinders measuring 23 in. -and 13J in., with a 10J in.
stroke, and compresses 2,000 cubic feet of air per minute.
The compressor is direct coupled to a 360-horse power West-
inghouse motor, running at 285 revolutions per minute.
Automatic cut-off gear is attached, which stops the motor
when the pressure reaches 80 lb. per square inch, and re-
starts when the pressure falls to 60 lb. The compressed air
is used underground for coal cutting, duplicate pumps, and
auxiliary. haulage engines near the coal-face, no electric
power being used more than 100 yds. away from the pit
bottom.

The electrical plant consists of a 1,000 kw. Westinghouse
mixed-pressure turbo-generator, running at 3,000 revolutions
per minute, and producing three-phase current at 50 periods
and 550 volts, with a Leblanc jet condenser requiring 1,780
gallons per minute at full load. The vacuum is 28 in., and
the delivery pump and air pump worked from the same shaft
are direct driven by a 70-horse power motor running at 480
revolutions per minute. All the cables were supplied by
Messrs. Callender and Company Limited, the main cables
being three-core and double-armoured. The Rateau heat
accumulator, 30 ft. long by 7 ft. in diameter, is capable of
bridging a stop of 30 seconds, and deals with 24,500 1b. of
steam per hour, at an absolute pressure of 18-16 lb. per
square inch. The water for the condenser is pumped up
14 in. cast iron pipes from the river to the main tank by a
pair of centrifugal Rees Roturbo pumps (one used as a
stand-by), driven by 45-horse power Westinghouse motors
running at 1,440 revolutions per minute. The tank is of
concrete, approximately 40 ft. square by 10 ft. in height,
with a capacity of 54,000 gallons. The walls are 2 ft. thick.
The tank is divided into the suction side, and the delivery
from the condenser, or “ hot well ” side. Prom this hot
well the boiler feed is taken, the surplus water running back
to the river through 24 in. earthenware pipes.

As already stated, supply is also purchased for power and
lighting from the Yorkshire Electric Power Company, whose
generating stations are situated at Thornhill (near Dews-
bury) and at Barugh (near Barnsley). The supply is
brought into the sub-station by 10,000 volt overhead feeders
of three-phase current. These feeders are in duplicate, and
form part of the company’s general transmission system.
The sub-station is a fireproof building of three storeys, and
immediately adjoins the compressor house. Arresters of
the horn type for protection against excess pressure due to
lighting, etc., are fixed in the top chamber. In the middle
chamber below it the high pressure switch gear is fixed in
brickwork cells. The supply through each feeder is con-
trolled by a separate oil switch connected to the busbars,
from which the step-down transformers are supplied; a
separate oil switch is used for each transformer, and is fitted
with automatic protection against disturbances due to fault
or overload. The operating handles for these switches are
mounted on the wall inside the compressor room, and are
accessible from an operating platform. Three step-down
transformers of the oil-cooled type and of 400 kw. capacity
each are installed in the bottom chamber, making a total
capacity of 1,200 kw., the pressure being transformed down
to 550 volts on the secondary side. The low pressure side
of each of these transformers is connected through the
power company’s meters to the colliery main switchboard,
from which the supply is distributed and controlled to the
various parts of the surface and workings.

The screens and gantries were built by Messrs. Head,
Wrightson and Company Limited, and' consist of four
tipplers, four coal belts, three cobble belts, two transverse
muck belts, one conveyor belt to bunkers for drossy coal,
and five Marcus screens. The whole are driven by West-
inghouse motors of an aggregate of 300-horse power. All
coal passing through a 1| in. square mesh goes to the
washery, and from one screen only that passing through a
3 in. round mesh.

The Baum washery was supplied by Messrs. Simon Carves
Limited, and is capable of dealing with 75 tons per hour,
washing all coal of less than 3 in. cube. The washery is
driven by Westinghouse motors of a total (two pumps and
power for machinery) of 190-horse power. The main feed
hopper is charged from the screens by a Reddaway motor-
driven 2 ft. canvas belt, running at 520 ft. per minute.
After being washed the coal is sub-divided into the following
classes : (1). trebles, 3 in. to 1J in.; (2) doubles, 1J in. to
$ in.; (3) singles, f in. to 7-16 in.; and (4) smudge below
7-16 in.

The shipping staiths were built by Messrs. Head, Wright-
son and Company Limited, and consist of two staiths, each
capable of dealing with 100 tons per hour. The coals are
end-tipped from an inclined table. Westinghouse 30-horse
power motors raise this table through David Brown gears
running in oil. British Thomson-Houston motors of 20-
horse power each are employed for raising and lowering the
jibs. The empty wagons from the staiths are drawn to
the top of the incline by two electric capstans built b^T
Messrs. Clarke, Chapman and Company Limited, each of
which is capable of exerting a rope-pull of 2,000 lb. at a
speed of 120 ft. per minute. These two staiths deal with
an average of 8,000 tons per week.

The headgears were also built by Messrs. Head, Wrmht-
son and Company Limited, and are both of steel lattice-
work, 65 ft. high, and weigh approximately 70 tons each.
The downcast guides are of wood, and those for the upcast
of rope.

The boilers were supplied by Messrs. Spurr, Inman and
Company (Wakefield), and consist of six Lancashire boilers,
30 ft. in length by 9 ft. in diameter, working at a pressure
of 100 lb. per square inch, with Bennis forced draught
stokers. Five of these boilers are in constant use, one being
used as a stand-by. The two adjacent boilers and chimney
are part of the old plant; as .they are never used, they will
probably be pulled out. The'boiler-feed is taken from the
hot well of the turbine pond through an Erith water
softener (heated by surplus exhaust steam from the Rateau
accumulator), and thence is pumped through a Green econo-
miser into the boilers. The Green economisers have a nest
of 400 tubes. They deal at present with about 4,500 gallons
of water per hour from the hot well side of the turbine pond,
which passes through a softener, and enters the boilers at
about 250 degs. Fahr. All the high pressure mains are of
steel, and have been installed by Messrs. Stewarts and
Lloyd Limited. An interesting feature in the piping is the
length of the low pressure main to the accumulator : this
consists of 65 yds. of 12 in. piping with electrically welded
joints, making practically a single tube, except where broken
by the expansion joint.

The stables and corn store were built in 1909 by Mr. L. J".
Gallagher, of Castleford, and consist of stables, motor-garage
and harness repair shop under one roof : the other block con-
sists of corn stores and carriage house. All the fodder is

prepared and sent down the pits from this building, the
chopped hay being put through an electrically driven Bam-
ford cutter, fitted with a dust extractor.

The lamp cabin was built in 1911 by the same firm as that
which built the stables. It has a fireproof roof, and glazed
brick interior. The fittings were supplied by Messrs.
Ackroyd and Best Limited, and include motor driven clean-
ing machines and apparatus for the electric lighting of the
lamps. The underneath portion of this building is used as
a storeroom.

The weighbridges were built in 1910 by Messrs. S.
Denison and Son Limited, and consist of a tandem weigh-
bridge of 60 tons capacity, each bridge dealing with 30 tons
separately.

A fitted room kept at a proper temperature and adjoining
the offices has been provided, where first-aid can be ren-
dered. A 24-horse power Dennis motor-ambulance has
recently been purchased, the whole cost of which is being
defrayed by the workmen at the collieries.

Underground Plant.

The bulk of the water is collected at the level of the upper
Haigh Moor seam 130 yds. down the shaft. The plant
dealing with this consists of two Rees Roturbo six-stage
centrifugal pumps, with phosphor-bronze impellers and
shafts. These will each deal with 36,000 gallons per hour
at a head of 460 ft. They are direct driven by two British
Thomson-Houston squirrel-cage motors of 140-horse power
each, running at 1,420 revolutions per minute. One
compressed air pump is kept as a stand-by. At the
Silkstone bottom is installed a vertical three-throw
ram pump, with rams 5} in. by 6 in. stroke. The
pump is belt driven by a 11-horse power Westinghouse
squirrel-cage motor running at 850 revolutions per minute,
and delivers to the Haigh Moor pumps. At the Beeston
bottom is one small compressed air Tangye 8 in. by 4 in.
single-acting pump delivering to the Silkstone sump. At the
Warren House level (water pit) are two Rees Roturbo hori-
zontal centrifugal pumps. The pumps, with a capacity of
12,000 gallons per hour at a head of 191 ft. were built by
the Electric Construction Company Limited, and are driven
by two squirrel-cage motors of 2Lhorse power, running at
1,430 revolutions per minute.

LEDSTON LUCK COLLIERY.

This colliery belongs to the Micklefield Coal and Lime
Company Limited, is situated in the eastern portion of the
West Yorkshire coalfield, about nine miles from Leeds, and
about 55 miles from Hull, and is sunk to the Beeston Bed,
which is reached at a depth of 300 yds. The seam dips
south-westwards at a gradient of one "in 18. The downcast
shaft, which is 18 ft. in diameter, is tubbed to a depth of
130 yds., and is fitted up to work the Beeston Bed. The
upcast shaft, which is 15 ft. in diameter, is tubbed to a
depth of 120 yds., and is sunk to the Beeston Bed, but is
fitted up to work the Silkstone Bed, which is reached at a
depth of 208. yds. Both shafts are connected with the Peck-
field shafts by means of a drift through a 45 yds. fault.

Steam was used only for sinking the shafts, and when these
were completed, the boilers were shut down, and the whole
colliery is now worked entirely by electrical power.

In the No. 1 downcast shaft the tubbing is of the plain
type, and is wedged in the ordinary manner. The shaft is
fitted.up to wind 1,500 tons per day in 10 hours. The cages
are single deck, and carry three tubs of 10 cwt. each, four
rope guides being attached to each cage. The winders
consist of two direct-current motors, one on each side of the
drum, which is 11 ft. in diameter and parallel. The motors
are supplied with current at 220 volts from the Yorkshire
Electric Power Company’s mains, the generating station
being 20 miles distant from the colliery. The current is
supplied at 2,000 volts to a 280 horse-power three-phase
motor; this drives a dynamo on the same shaft, to which is
coupled a nine tons flywheel, the whole being termed an
“ Ilgner ” set, which supplies direct current to the motors on
the drum shaft at a pressure of 220 volts. The drum is
provided with two sets of post brakes, held off by a com-
pressed air engine. When the brakes are to be applied,
the compressed air is cut off, and the brakes are put on by
means of weights attached to a lever on a shaft connecting
the two sets of brakes. One or other of the above brakes
can be used as an emergency brake, and is released by a
brake magnet. The depth indicator and controller consists of
two spindles, with an arrangement for releasing the emer-
gency brake in the case of overwinding, and of retarding
apparatus for bringing back the controller lever to the “zero”
position as the cage approaches the bank. A liquid starter
is provided for the three-phase motor of the Ilgner set, with
an arrangement for maintaining the load constant. Com-
pressed air for the brake cylinder is provided by a small
compressing plant on a cast iron bedplate, driven by a belt
from a direct current shunt wound 7J horse-power motor at
220 volts, running at 1,100 revolutions per minute-, with an
automatic starter and switch operated by means of com-
pressed air (dependent upon the pressure of air in the
receiver) for switching the motor in and out. This electric
winder equipment was made by the Lahmeyer Electrical
Company (now the A.E.G. Electric Company Limited).

The winder for No. 2 upcast shaft consists of two plain
cylindrical drums, driven by one continuous current motor
through Citroen gearing having a ratio of 12 to one. The
winding motor is a direct current reversible shunt wound
motor, with a half-coupling on the shaft for coupling to the
gear pinion shaft. The armature voltage varies from + 290
to — 290, and the speed of the motor is 425 revolutions per
minute. This motor is capable of lifting the total unbalanced
load at the top end of the shaft, or, in case of emergency, of
hoisting the unbalanced cage from the bottom of the shaft
to the top. The converter set consists of one three-phase
50 period slip ring motor; with a normal output of 225 brake
horse-power. The voltage is 2,000, and the speed 950/830
revolutions per minute. This motor drives a direct current
starting dynamo with an output sufficient for supplying
current to the winding motor, the voltage being + 290 to
— 290, and the speed 950/830 revolutions per minute. One
direct current exciter dynamo of sufficient output for the
necessary excitation of the winder motor and starting
dynamo has a voltage of 220, and runs at a speed of 950/830
revolutions per minute. There is no flywheel to this set. but
provision has been made in the foundations for installing
one if found necessa^v. The depth indicator and controller
consists of two spindles, with an arrangement for releasing
the emergency brake in the case of overwinding, and of
retarding apparatus for bringing back the controller lever
to the zero position as the cage approaches the bank, similar
to the arrangement provided in the case of the No. 1 winder.
The liquid starter for this Ilgner set is the same as that at
the No. 1 winder. Compressed air for the brake engine is
taken from the general compressing plant. The two cylin-

drical drums are 8J feet in diameter by 4 ft. 3 in. in width,
and are fitted wTith post brakes.

Ventilation is. provided by a double inlet Walker fan,
18 ft. in diameter, with a capacity of 300,000 cu. ft. per
minute, at a water gauge of 4 in. The fan is driven by a
special three-phase commutator motor of 360 horse-power of
A.E.G. manufacture, through the medium of 16 in. cotton
ropes. The speed of the motor may be varied between 600
and 260 revolutions per minute by means of shifting brushes.
The voltage is 2,000 at 50 periods, and the ratio of the pulleys
on the motor shaft and fan shaft is about four to one.

The air compressing plant consists of one Robey high speed
vertical compressor, dealing with 2,000 cu. ft. of air per
minute. The two stage cylinders are 30 and 19 in. in
diameter respectively, and have 11 in. stroke, and the engine
runs at a speed of 250 revolutions per minute. The final
pressure of the air is 80 lb. per sq. in. The compressors
are driven by an A.E.G. three-phase motor of 400 horse-
power at 2,000 volts, 50 periods, and is coupled direct to the
compressor. One Beiliss and Morcom high speed vertical
two stage compressor of a capacity of 3,000 cu. ft. per
minute at 243 revolutions per minute, with a final pressure
of 80 pounds, is driven by a Sandycroft direct coupled two-
speed cascade motor of 550 brake horse-pow’er at 243 revolu-
tions per minute, or of 360 brake horse-power at 164 revolu-
tions per minute, at a pressure of 2,000 volts and 50 periods.
One Ingersoll belt-driven compound or two stage compressor
with a capacity of 500 cu. ft. per minute, and a final pressure
of 80 lbs. per sq. in., is run by an A.E.G. three-phase motor
of 100 brake horse-power, at 2,000 volts and 50 periods,
when running at a speed of 485 revolutions per minute.

In No. 1 shaft a Mather and Blatt turbine pump, designed
to deliver 100 gallons per minute against a total head of
930 ft., runs at a speed of 2,900 revolutions per minute, and
is direct coupled to an alternating current motor of 70
brake horse-power, at 400 volts and 50 periods. This pump
raises the water found in the Beeston seam to the surface.
In No. 2 shaft a two stage turbine pump, capable of raising
1,200 gals, per hour to a vertical height of 180 ft., runs at
a speed of 1,440 revolutions per minute; it is coupled direct
to a three-phase motor of 30 brake horse-power running at
1.440 revolutions per minute at 400 volts and 50 periods.
The pumps were constructed by Messrs. Hathorn, Davey and
Company, and the motor by the A.E.G. Electric Company
Limited. This motor is fixed at the Haigh Moor seam
44yds. below the surface. The water is used for cooling the
compressors, and is afterwards conducted in pipes to the
boilers at Beckfield Colliery.

The Yorkshire Electric Bower Company’s mains convey
current at a pressure of 10,000 volts, and this is transformed
by the company to 2,000 volts for use at the colliery. This
is again transformed down to 400 volts for pumping, pit
bottom haulage, and lighting.

After the coal is raised, it is taken by endless rope to the
screens at Beckfleld. This roneway is worked by a 120
horse-power motor, supplied with current from the same
source at 2,000 volts and 50 cycles. The empty tubs are
elevated by the rope sufficiently to allow them to gravitate
to both pits ; the full tubs also gravitate to the ropeway.

NORTH STAFFORDSHIRE INSTITUTE OF
MINING AND MECHANICAL ENGINEERS.

Signalling in Mines.

An informal meeting of the members of this institute
was held at the Central School of Science and Tech-
nology, Stoke-on-Trent, on Tuesday, the 5th inst., when
a discussion took place on the mine signalling apparatus
required to comply with the General Regulations of
1913 made under the Coal Mines Act, and which come
into operation on July 1 next. In addition to the mem-
bers of the institute, a number of the local winding
enginemen—members of the National Amalgamated
Union of Enginemen and Stokers—attended the meet-
ing, and joined in the discussion.

Several makers of signalling apparatus exhibited
appliances designed to comply with the regulations,
which require both audible and visible indications to
be given to the winding engineman. Apparatus, both
of the electrical and mechanical types, were on view,
and all of the appliances were subjected to thorough
inspection and trial. These appliances were described
and illustrated in last week’s issue of the Colliery
Guardian.

In the course of the discussion which ensued, the
Bresident of the institute (Mr. Hugh Johnstone, divi-
sional inspector of mines) said he wished to point out
to them that there had been a misunderstanding on the
part of several of the makers of apparatus as to what the
regulation in question meant. The official reading of
the regulation was somewhat different from that which
had been held by several of the makers, and also by a
good many colliery managers. The regulation, No. 95,
stated : “ In connection with every winding engine there
shall be provided an appliance which shall automatic-
ally indicate in a visible manner to the winding engine-
man (in addition to the ordinary signal) the nature of
the signal until the signal is complied with.” They
knew that the system of signalling had varied in
different mines, and the Royal Commission on Mines
recommended very strongly that a universal system of
signalling should be adopted throughout the mines of
the country, especially so far as the raising and lower-
ing of persons was concerned. When the regulations
were under consideration by the committee which was
presided over by Lord Mersey, a committee was
appointed, representing the Mining Association, the
Miners’ Federation, and the Enginemen’s Union, and
they formulated the code of signals which was embraced
in the regulations. It was pointed out that the men
having been in the habit of using different signals, the
change might result in accidents until they became used
to the new code, and in order to obviate that, visible
signals were suggested. It was accordingly agreed
unanimously, and accepted by the Home Office, that in