In any series or sequence of chemical reactions used to leach a product
from its ore, the slowest in the chain. Pryor, 3
a. Theoretical horsepower of an engine based on dimensions and speed.
Nichols, 1
b. Power of an engine according to a particular standard.
Nichols, 1
The kilowatt power output that can be delivered continuously at the rated
output voltage. It may also be designated as the 100% load or full-load
rating of the unit. Coal Age, 1
The current derived from the rated load and the rated output voltage.
Coal Age, 1
The current specified as the basis of rating. Coal Age, 1
a. The distance the bit penetrates a rock formation in a unit of time,
such as inches (centimeters) per minute or feet (meters) per hour.
Long
b. In coal mining, the number of feet (meters) between the coal face at
the beginning and at the end of a workshift.
See:gradient
In crushing practice, these rates are (1) based on crusher dimensions,
wherein the largest cube that will enter is compared with the largest that
can be discharged, or (receiving opening) / (discharge opening); the
receiving opening is measured from the top of the movable member to the
top of the stationary member; and (2) based on actual products; (a)
overall reduction ratio = (mean size of feed) / (mean size of product);
(b) individual reduction ratio = (size most abundant in feed) / (mean size
of grading band concerned). South Australia
See:liveingite
See:liveingite
a. A hole drilled at an angle to the main hole by means of a deflection
wedge. Long
b. A small-diameter pilot-type hole drilled a short distance ahead of a
larger diameter hole to stabilize a smaller diameter bit and core barrel
when used to core a limited portion of the borehole. After core drilling
is completed, the rathole is reamed out and the larger size hole advanced,
usually by some noncoring method. Long
c. A small sump or settling pond in which the larger sized cuttings from a
drill hole are collected between the top of the drill hole and the main
settling pond. Long
d. A slanting hole, perhaps 25 ft (7.62 m) deep, used for adjusting or
lubricating the swivel on a grief stem. The start of a hole for rotary
drilling. Hess
A bit designed and used to drill the first portion of a deflected hole
alongside and beyond the deflection wedge; also, a bit used to drill a
rathole. CF:wedge bit
The act or process of drilling a deflected or pilot hole.
See also:rathole
The maximum capacity of a drill hoist or a prime mover, such as an engine,
motor, or pump; generally the maximum safe capacity. Long
A flume used for purposes of control. Hammond
An instrument used to measure the ratio of two differences in potential.
AGI
a. The mineralogical composition of a material as deduced from chemical
analysis.
b. The resolution into chemical types of a mass of rock or coal.
Francis, 2
a. The percentage by weight that the absorbed water bears to the dry
weight of the stone.
b. The ratio (A), expressed as a percentage, of the volume (Vp) of the
pore space in a rock to the weight (W) of the rock when dry, A = 100 Vp/W.
Holmes, 2
(Weight of ore fed) / (Weight of concentrate produced). Pryor, 3
The ratio of the percentage of valuable material in the concentrate to the
percentage of the valuable material in the original material.
a. The relationship between the maximum size of the stone which will enter
a crusher, and the size of its product. Nichols, 1
b. The ratio of enrichment with respect to the sought mineral: (Assay
value in feed) : (Assay value in concentrate).
See also:reduction ratio