A ram fed by a compressed-air pipeline. The piston is about 8 in (20 cm)
in diameter, giving an area of 50 in2 (323 cm2 ) and
exerts a pushing force of up to 4,000 lb (1,800 kg). Nelson
A compressed-air tool used for driving rivets. See also:rivet
Hammond
An air-driven rod puller. See also:rod puller
The branch of physics that deals with the mechanical properties of gases,
such as their pressure, elasticity, density, and also of pneumatic
mechanisms; sometimes it includes acoustics. Standard, 2
a. Shaft sinking with the aid of a drop shaft fitted with an air-tight
deck to form a working chamber. See also:manlock
b. The caisson-sinking process now largely obsolescent in mining practice.
Nelson
A system of filling mined cavities in which crushed rock is carried along
a pipeline by compressed air and discharged at high velocity into the
space to be packed, the intense projection ensuring a very high density of packed material. For stowing shallow workings--up to 200 yd (183 m) in
depth--the stowing plant may be installed on the surface. The air pressure
is about 60 psi (414 kPa). For deeper workings, the plant may be installed
underground, and the crushed rock taken down from the surface. The stowing
pipes are about 5 to 6 in (approx. 13 to 15 cm) in diameter. The system is
often employed if important surface structures require protection. The
material used is from old dirt heaps, screen dirt, and washery rejects.
The material is crushed to -2-1/2 in (-6.35 cm) and preferably without the
-1/2-in (-1.27-cm) material. See also:air-stowing machine;
crusher stower; hydraulic stowing; low-pressure air stower.
Nelson
An appliance for the dry cleaning of ore or coal. It consists of a
perforated deck, with vertical ribs or riffles, which is reciprocated; the
motion keeps the bed of raw coal sufficiently mobile for the blast of air
from below to effect a process of stratification (or layering). The coal
rises to the surface, with dirt at the base and a central layer of
middlings. See also:Birtley contraflow separator; Kirkup table;
Vee table; air table. Nelson
Essentially a long-stroke piston with a mushroom-shaped foot about 4 in
(10 cm) in diameter. It operates on compressed air, which is used to lift
the piston and footpiece; their combined weight, in falling, supplies the
impact. Carson, 1
Tool operated by air pressure. Crispin
System composed of: a compressor, which provides airflow; a feeder, which
meters the flow of material into a pipeline; and the pipeline-- for
transporting coarse, dry, noncohesive material. SME, 1
A special type of water barrel for removing water from a shaft sinking. By
means of a hose connection to an air pump at the surface, a partial vacuum
is created inside the barrel and the water lifts the valve and fills the
barrel. The hose is then detached and the barrel is hoisted to the surface
and discharged. Also called vacuum tank. Nelson
Said of a rock or mineral deposit formed by a gaseous agent.
CF:hydatogenic; hydatopneumatogenic; pneumatolytic. AGI
Alteration of a rock or crystallization of minerals by gaseous emanations
derived from solidifying magma. Adj: pneumatolytic. AGI
A term used in different connotations by various authors and perhaps best
abandoned. It has been used to describe: (1) the surface effects of gases
near volcanoes; (2) contact-metamorphic effects surrounding deep-seated
intrusives; (3) that stage in igneous differentiation between pegmatitic
and hydrothermal, which is supposed to be characterized by gas-crystal
equilibria; and (4) very loosely, any deposit containing minerals or
elements commonly formed in pneumatolysis, such as tourmaline, topaz,
fluorite, lithium, and tin, and hence presumed to have formed from a gas
phase. CF:pneumatogenic
Contact metamorphism in which the composition of a rock has been altered
by introduced gaseous magmatic material.
That stage in the cooling of a magma during which the solid and gaseous
phases are in equilibrium. AGI
A combining form taken from the Greek meaning lung, and used in connection
with the terminology of geologic processes and effects involving gases and
vapors. Stokes
A disease of the lungs caused by habitual inhalation of irritant mineral
or metallic particles. It occurs in any workplaces where dust is
prevalent, such as mines, quarries, foundries, and potteries. Also called
miner's asthma; miner's consumption; miner's lung. Also spelled
pneumonoconiosis; pneumonokoniosis. CF:anthracosis; silicosis.
See also:phthisis
See:pneumoconiosis
a. A localized enrichment; a crevice in bedrock containing gold; a rich
patch of gold in a reef.
b. A rich deposit of mineral, but not a vein.
c. A bin, of a capacity equal to the skip, used at the shaft bottom of an
underground mine for quick and accurate skip loading.
See also:shaft pocket; measuring chute. Nelson
d. A receptacle, from which coal, ore, or waste is loaded into wagons or
cars. Fay
e. A ganister quarryman's local term for masses of rock, 30 to 50 ft (9.1
to 15.2 m) in width, that are worked out and loaded, leaving buttresses of
untouched rock between them to support the upper masses. Fay
f. A hole or depression in the wearing course of a roadway. Fay
g. A local accumulation of gas. Hudson
h. A bulge, sop, or belly in a lode or bed. See also:belly
Arkell
i. A cavity, whether filled with air, water, mineral, or gravel.
Arkell
j. In pegmatites, the central openings lined with crystals, including
those of gem species. Sinkankas
In pillar extraction, a method in which lifts are mined in the same way as
in the open-end method, except that a fender of coal or a series of small
coal stumps is left adjacent to the gob as the lift is advanced. After the
lift is completed, the fender or stumps of coal are blasted, and sometimes
part of this coal is recovered. Woodruff