Relays used to automatically reclose electrically operated circuit
breakers. They limit the duration of power failures in many instances
where faults clear themselves quickly. Most reclosing relays attempt to
close a breaker three times before locking it out. The time interval
between reclosures is predetermined. Lockout means that after the third
attempt fails to keep the breaker in, the relay will not function until it
is reset manually. Such relays can be designed to operate more than three
times before locking out, with the number of reclosures depending on the
requirements and design of the system. Coal Age, 3
Appliance for recording the working time of machines such as cutter
loaders, conveyors, etc. A vibrating type, fitted on the equipment itself,
marks on a chart a straight line when the machine is idle and an
oscillating one when working. Nelson
An instrument designed to take samples of mine gases or water at
predetermined times or intervals.
Automatic removal of samples at timed intervals from a passing stream of
ore, pulp, or solution. Pryor, 3
A water sprinkling device closed by a metallic alloy that melts at a low
temperature. In case of fire the alloy melts, releasing a water spray.
These devices are used in wood-lined shafts and timbered bottoms,
sometimes by legal requirements. Zern
This term includes at least three different systems: (1) fully automatic
winding in which no driver, banksman, or onsetter is employed; (2)
pushbutton automatic winding, similar to the above except that the
operation is started by a pushbutton by the banksman or onsetter; and (3)
cyclic winding in which the driver takes off the brakes and throws over
the control lever at the beginning of the wind. Sinclair, 5
a. A process of recrystallization of an igneous rock under conditions of
falling temperature, attributed to the action of its own volatiles, e.g.,
serpentinization of peridotite or spilitization of basalt. AGI
b. The alteration of an igneous rock by its own residual liquors. This
process should rather be called deuteric because it is not considered to
be metamorphic. See also:deuteric
Alteration of a recently crystallized igneous rock by its own last
water-rich liquid fraction, trapped within the rock, generally by an
impermeable chilled border. CF:autopneumatolysis; autometamorphism.
AGI
A dark-green to nearly black variety of gahnite. Schaller
a. Said of the holocrystalline texture of an igneous or metamorphic rock,
characterized by crystals bounded by their own rational faces. Also said
of a rock with such a texture. The term idiomorphic is more common in U.S.
usage. CF:xenomorphic
b. A synonym of euhedral, obsolete in U.S. usage, but generally preferred
in European usage. Syn:automorphic-granular; euhedral. AGI
See:automorphic
Autometamorphism involving the crystallization of minerals or the
alteration of a rock by gaseous emanations originating in the magma or
rock itself. CF:autometasomatism
A device for controlling dust carried by loaded conveyors. A liquid medium
is sprayed on the conveyor load only when moving and not when stationary,
or when the belt is running unloaded. The spray control is placed
centrally beneath the conveyor belt and a load causes the belt to deflect
and rotate the driving pulley, which causes the controller valve to open.
A belt stoppage or no load causes the valve to close. Nelson
A stoper or light compressed-air rock drill, mounted on an air-leg support
that not only supports the drill but also exerts pressure on the drill
bit. Nelson
A special-type of transformer whose use in mines is limited to apparatus
for starting induction motors of the squirrel cage type. The winding is a
common one for primary and secondary, and the two circuits are
electrically in contact with each other. Mason
Organism capable of growth exclusively at the expense of inorganic
nutrients. See also:chemolithotroph; photolithotroph.
a. An automatic multielement-indexing X-ray spectrograph, capable of the
qualitative and quantitative determinations of as many as 24 elements in a
single sample. Choice of the elements may be made from magnesium through
all the heavier elements. The device measures the intensity of an emitted
wavelength band from a standard sample and compares it with the intensity
of a like band from an unknown sample. These data are presented in the
form of a ratio of one intensity to the other. Nelson
b. An automatic multielement-indexing X-ray spectrograph.
a. A tetragonal mineral, 2[Ca(UO2 )2 (PO4 )2
.10-12H2 O] ; radioactive; yellow to pale green; fluorescent; forms
scaly or foliated aggregates; results from oxidation or hydrothermal
alteration of uranium minerals; an ore of uranium. Syn:calcouranite
b. The mineral group autunite, fritzscheite, heinrichite, kahlerite,
novacekite, sabugalite, saleeite, sodium autunite, torbernite, troegerite,
uranocircite, uranospinite, and zeunerite.
a. Tools or other equipment, such as a pump, drill rods, casing, core
barrel, bits, water swivel, safety clamp, etc., required for use with a
drill machine to carry on specific drilling operations. Long
b. A helper or standby engine or unit. CF:accessory
A supplementary anode placed in a position to raise the current density on
a certain area of the cathode to get better plate distribution.
ASM, 1
A cylinder, operated by compressed air, that is used to assist the main
engine of a compressed-air shaker conveyor, esp. where the conveyor cannot
develop a sufficient amount of forward acceleration because of grades. The
auxiliary cylinder is attached to the conveyor by a driving chain and to a
prop by a fixing chain. Jones, 1