a. Steel cutting point used on a coal-cutter chain.
See also:coal-cutter pick
b. A miner's steel or iron digging tool with sharp points at each end. It
weighs from 3 to 6 lb (1.4 to 1.7 kg) and has a wood handle, fitted to the
center or head, from 2 to 3 ft (0.6 to 0.9 m) in length.
Syn:miner's pick
c. To dress the sides of a shaft or other excavation.
d. To remove shale, dirt, etc., from coal.
e. To select good ore out of a heap.
f. In seismic prospecting, any selected event on a seismic record.
AGI
A short conveyor which takes the coal from, and advances with, a face
power loader or continuous miner. It delivers the coal onto a gate
conveyor over which it runs on a bogey.
See also:long piggyback conveyor
See:pick miner
A double-tube core barrel in X-group sizes. The distinguishing feature of
the Pickard barrel is that when blocked, the inner barrel slides upward
into the head, closing the water ports and stopping the flow of the
circulating liquid; no additional drilling can be done without irreparably
damaging the bit until the barrel is pulled and the blocked inner tube is
cleared. Long
In bituminous coal mining, a person who carries sharpened picks or bits
for coal-cutting machines to the machine operator in underground working
places. Also called pick carrier. DOT
A breaker developed as the mechanical equivalent of the miner's pick. In
the modern type, the picks are mounted on alternating arms, the primary
and secondary picks being at different spacings so that breaking is
performed in two stages. The breaker and plate belt are usually supplied
as a standard unit driven from a common motor. Nelson
See:pick boy
a. An employee who picks or discards slate and other foreign matter from
coal in an anthracite breaker or at a picking table, or one who removes
high-grade ore, iron, or scrap wood from ore as it passes on a conveyor
belt to crushers. BCI; DOT
b. A mechanical arrangement for removing slate from coal.
c. A miner's needle, used for picking out the tamping of a charge that has
failed to explode. Syn:piercer
A monoclinic mineral, MgAl2 (SO4 )4 .22H2 O ;
hallotrichite group; forms acicular crystals and tufts; astringent taste;
a product of surficial acid sulfate attack on aluminous rocks in mines and
arid regions. Syn:magnesia alum
a. A sighting hub. See also:backsight hub; foresight hub. Long
b. A short ranging rod about 6 ft (1.8 m) long. An iron rod, pointed at
one end, and usually painted alternately red and white at 1-foot (30.5-cm)
intervals; used by surveyors as a line of sight. See also:range pole
CTD; Fay
a. Operation performed between mine and mill in which waste rock, wood,
detritus, steel (tramp iron), or any specially separated mineral is
removed from the run-of-mine ore material by hand sorting. Usually done
during transit of material on belt conveyors, preferably after very large
lumps and smalls have been screened off and the ore to be picked has been
sufficiently washed to display a true surface. Also done on a picking
table, a rotating circular disc around which hand sorters stand or sit to
remove part of the ore fed radially from a central point. Picking can also
be mechanized. Pryor, 3
b. The falling of particles from a mine roof about to collapse.
c. Extracting over a prolonged period an undue proportion of the richest
ore from a mine, thus lowering the average grade of the remaining ore
reserves; "picking the eyes out" of a mine.
d. Rough sorting of ore. Webster 2nd
A continuous conveyor (e.g., in the form of a rubber belt or of a steel
apron, steelplate, or link construction) on which raw coal or ore is
spread so that selected ingredients may be removed manually.
Syn:picking table; picking chute; picking conveyor. BS, 5
A chute along which workers are stationed to pick slate from coal.
See also:picking belt
See:picking belt
Mining in which only the high-grade spots are taken out. Hoover
A flat, or slightly inclined, platform on which the coal or ore is run to
be picked free from slate or gangue. See also:picking belt;
picking conveyor.
The pattern to which the picks are set in a cutter chain. In this respect,
it may be a balanced or an unbalanced cutter chain. Pick lacing is
important as it has a bearing on the stability of the machine, on dust
formation, and even on dangerous sparking. Nelson
a. An acid dip used to remove oxides or other compounds from the surface
of a metal by chemical action. Lowenheim
b. To use such an acid dip.
The process of removing scale or oxide from metal objects by immersion in
an acid bath to obtain a chemically clean surface prior to galvanizing or
painting. Hammond
Coal-cutting machine which acts percussively, and cuts with a large chisel fixed at the end of a piston reciprocated by compressed air in much the
same way as a rock drill is operated. Kiser
A mine in which coal is cut with picks. Kiser