In alluvial mining, one that loosens the alluvium by means of a cutting
ring, at the end of a suction pipe through which the products are pumped
up for treatment. Pryor, 3
A hydraulic dredge in which the suction action is augmented by a rotating
propeller that operates at the point of suction. The cutterhead performs
two functions: it cuts into and loosens compacted soils and soft rock such
as coral, and it increases dredge capacity by channeling the soils into
the end of the suction pipe. The efficiency of a dredge is based on its
capacity to handle soils rather than water, and the cutterhead serves to
maintain an optimum ratio of about 1 ft3 (0.028 m3 ) of
soil handled per 5 ft3 (0.14 m3 ) of water.
Carson, 1
A longwall machine that cuts and loads the coal onto a conveyor as it
travels across the face. See also:loader
A plow-type cutter loader developed for use in hard coal seams. It has
four horizontal stepped precutting blades, which make a precut from 8 to
12 in (20.3 to 30.5 cm), to weaken the coal immediately in front of the
machine. It can be single or double ended, and is hauled along the face by
winches. The coal is loaded onto a panzer conveyor, which is advanced
behind the machine by compressed air rams. See also:plow
Nelson
A passage cut through the coal, connecting two parallel entries.
See also:crosscut; breakthrough; jack hole. Rice, 1
a. The opening made by shearing or cutting.
b. Low-grade ore or refuse obtained from beneficiating ore.
c. The operation of making openings across a coal seam as by channeling,
or beneath a coal seam as by undercutting.
d. Excavating. Nichols, 1
e. Lowering a grade. Nichols, 1
f. Eng. The end or side of a stall next to the solid coal where the coal
is cut with a pick in a vertical line to facilitate breaking down;
channeling.
g. N. of Eng. The operation of undercutting coal with a mechanical cutter.
The machine, which runs on electricity, employs two cutterpersons.
Trist
The sprocket chain that carries the steel points used for undermining the
coal with chain mining machines. Fay
a. The trimming of shaft walls to increase their sectional area.
Zern
b. Removing roughness or irregularities of a metal surface by abrasive
action. ASM, 1
a. The point or edge of a diamond or other material set in a bit that
comes in contact with and cuts, chips, or abrades the rock. Also called
cutting point. CF:cutting stones
b. That part of a bit in actual contact with rock during drilling
operations. Long
c. The leading edge of a lathe tool where a line of contact is made with
the work during machining. CF:cutter
That part of a bit containing the cutting points, excluding the points
inset as reamers. Long
A fluid, usually a liquid, used in metal cutting to improve finish, tool
life, or dimensional accuracy. On being flowed over a tool and a
workpiece, the fluid reduces friction, heat generated, and tool wear, and
prevents galling. It conducts heat away from the point of generation and
also serves to wash chips away. ASM, 1
The direction along a plane on which a diamond can be most easily abraded.
Long
The position in a coal seam in which a horizontal machine cut is made. The
normal cutting horizon is along the bottom of the seam.
See also:bottom cut
A power-driven machine used to undercut or shear the coal to facilitate
its removal from the face. BCI
The motor in a cutting machine that provides power for the operation of
the cutting chain. Jones, 1
a. The particles of rock produced in a borehole by the abrasive or
percussive action of a drill bit; excess material caused by the rubbing of
core against core or core against steel; erosive effect of the circulating
liquid; or cavings from the borehole. Also called drill cuttings;
drillings; sludge. CF:borings
b. The fragmental rock samples broken or torn from the rock penetrated
during the course of drilling. AGI
c. Eng. See:holings
d. See:bug dust
Composed of sharp, solid quartz grains and used as abrasive for sawing
stone; usually ungraded and about equivalent to a No. 1 sandblasting sand.
AIME, 1
a. The linear or peripheral speed of relative motion between a tool and a
workpiece in the principal direction of cutting. ASM, 1
b. See:feed rate
Diamonds set in a bit face having points or edges that will be in contact
with, and will cut or abrade, the rock when drilling. CF:cutting edge;
gage stone. Long
A cutting disk, the edge of which is impregnated with an abrasive, such as
diamond dust or aloxite. It is rotated at high speed in a coolant and used
to cut rock specimens into suitable thin sections for microscopic
inspection in transmitted light with a polarized-light microscope or,
after polishing, with a reflected-light (ore) microscope.
Plastic clay formerly used in England for making tobacco pipes; "pipe
clay." AGI