THE COLLIERY GUARDIAN

AND

JOURNAL OF THE COAL AND IRON TRADES.

Vol. CXII.

FRIDAY, AUGUST 25, 1916.

No. 2904.

AMERICAN COAL TIPPLES.

By H. J. EDSALL,

The bituminous coal miners have, -in the past,
been' content to ship coal just as it came from
the mine, that is, as run-of-mine coal, without,
in most cases, even removing the bone and slate.
With a greater production, and consequent broader
field for selection by the purchasers, the operators
found it advisable to be more particular as to
the kind of coal they shipped. With increasing com-
petition, the methods of preparation of the coal have also
gradually become more and more carefully perfected, so
that, with a well-designed modern tipple it is now
possible to ship half a dozen different sizes or various

combinations of these. In addition, the refuse is care-
fully picked out so that the coal which the consumer
finally receives will give good combustion and not cause
trouble with clinkers and burned-out grate bars.

As consumers are constantly becoming more insistent
in regard to the preparation and sizing of coal, the old

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Fig. 1.—Tipple Plant of the
Quemahoning Creek Coal Co.



it back and through a switch to another track. It can
then be allowed to run on down by gravity or lowered
with a chain haul if the dumping point is at a higher
level than that at which the trains of empties are made
up; or if it is necessary to take them uphill, this can be
done with a chain haul.

Transporting, Screening, and Picking the Coal.

If the coal is to be transferred from the dump hopper
to the preparation system, this can usually be accom-
plished in three ways : An apron conveyor may be used



clogged with coal and refuse, and allows the free passage
of undersized material.

The' most effective table is the corrugated apron con-
veyor on which the coal passes slowly along past the
pickers, so that the refuse can easily be removed. In
order to ensure effective picking, it is necessary to
remove the slack and small coal first, so that it will not
cover up and hide the refuse. On this account the
material is usually first screened into several sizes and
the different sizes carried by separate picking tables, or
the two sides of one picking table. In some cases it is
screened so that the fine coal is deposited first on the
picking table and the larger coal on top, where it can be
inspected and picked.

The refuse is usually dropped into chutes leading to a
flight conveyor or a drag-chain conveyor—that is, a wide
chain which slides along in a steel or cast iron trough
and pushes the material along without the use of any
flights or other attachments. The refuse can be then
delivered to a bin for removal by cars or delivered direct
to a car.

After the coal is screened and picked, it is delivered
either in the separate sizes to railroad cars on various
tracks or certain sizes are combined with others by
means of chutes, transfer conveyors, or a combination
of the two. The smaller sizes are delivered to the ears by
means of chutes, but as this method is apt to cause
excessive breakage of the larger sizes, loading booms are
substituted for chutes when loading these sizes in the
best modern tipples. A loading boom is simply a
hinged end of an apron conveyor which can be raised and
lowered, so that the coal can be deposited in the car with
a minimum amount of drop.

The railroad tracks should be arranged so that the
train of empties can be easily broken up and delivered
to the tracks under the tipple, and there should be room
on each track for at least one empty car directly back of
the one being loaded, so that it can take its place without
delay. The tracks should have sufficient grade so that
the ears will drop down quickly by gravity. On the
lower side of the tipple the tracks are brought together
again so that the cars can be passed over a scale to be
weighed, and then made up into trains.

The tipple of the Quemahoning Creek Coal Company,
at Harrison, Somerset County, Penn., shown in fig. 1,
is of somewhat novel design, is very simple, and is com-
paratively inexpensive. There are no shaking screens,
and only one apron conveyor, which also serves as a
picking table.

tipples are fast being replaced by others of modern
design. As a rule, this is not a case of reducing the
amount of labour or saving money in the cost of handling,
though, of course, any possibilities of improving the
methods of handling the mine ears, transferring the coal
from the head of the mine to the tipple, handling the
empty and loaded railroad cars should be considered
when a tipple is rebuilt.

Some of the essentials of a good tipple are as follows :

(1)	A satisfactory method of handling and dumping
the loaded mine cars and of taking care of the empties so
that there will be no excess of labour for these operations
or restriction in output due to congestion or troubles with
the system.

(2)	A satisfactory transfer of the coal from the dump-
ing point to the tipple, where it is not feasible to dump
the cars at the proper point for direct delivery to the
preparation system. Sometimes a conveyor from the
dumping point to the main preparation system is an
advantage, as it allows of preliminary picking.

(3)	A set of picking tables, screens, transfer conveyors
and refuse conveyors that will provide for the desired
preparation and mixing of the coal and the disposal of
refuse.

(4)	The proper loading devices that will load the
various sizes, or combination of sizes, into the railroad
cars with the minimum amount of breakage.

(5)	An arrangement of railroad tracks that will provide
for the easy and rapid handling of empty and loaded ears,
starting with the dividing up of the train of empty cars,
and finishing with the making-up of a train of loaded
ears.

For handling the cars and dumping them the usual
method is a standard crossover dump. The loaded cars
are brought to the dumping point in trains and
uncoupled j'ust as they go over' a knuckle and start down
a slight incline to the dump. Each car is caught by two
horns, or stops, while the dump is tripped by the operator
so that the car is tilted and the coal dumped out of it
and, as it rights itself, the stops are held down until the
car passes over and runs up to the kick-back, which sends

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Fig. 2—Tipple Plant of the Red Jacket Consolidated Coal and Coke Co.



on which the coal is carried along on corrugated over-
lapping steel slats attached continuously to two strands
of roller chain. Or this may be done with a flight con-
veyor made up of steel flights attached at intervals
between two strands of steel roller chain and acting as
pushers to shove the coal along in a steel trough; where
it is to be lowered down a steep incline these flights may
act as retarders to keep it from sliding down too rapidly.
Sometimes the coal is lowered down a hillside by means
of monitors which are similar to skip buckets, and are
raised and lowered with a double cable haul arranged so
that the two monitors balance each other.

For screening the coal the most satisfactory device is
undoubtedly a shaking screen with the screen part made
of the lip-screen type with slotted holes a little wider at
the lower end and a slight drop in the screen at the lower
end of each row of slots. This arrangement is self-
cleaning; that is, it keeps the holes from becoming









From the dump hopper the coal is delivered by a short
apron feeder to a section of lip screen, so that the fine
coal is. deposited on the apron back of where the lump
falls, thus bringing the larger coal on top so that it can
be properly picked. The apron conveyor takes the coal
up an incline to the proper level and along a horizontal
length where the picking is done. It is then delivered
over a bar screen, the large coal going over the end of the
screen into a chute with a hinged end and thence into
railroad cars on one track, while the slack goes through
the screen and into cars on another track. The refuse is
dropped in a hopper underneath the picking table and
taken away by means of mine care.

By using veil plates to cover up the screen, run-of-
mine coal can be loaded. The apron conveyor is 5 ft.
wide by 66 ft. long, centre to centre, and is driven by a
15 horse-power electric motor, which also drives the
apron feeder. The tipple structure is of wood. The con-