A borehole put down through an upper impervious bed into a lower pervious
one, from which a supply of water is obtained. See also:well
Nelson
a. Any kind of pump delivering from a well, shaft, or borehole.
BS, 10
b. An electrically driven pump located at the low point in the mine to
discharge the water accumulation to the surface.
c. Consists of a series of centrifugal pump impellers mounted on a single
rotating shaft. The casings are termed bowls and the impellers are of the
axial or mixed-flow type. Available in capacities ranging from 25 to
10,000 gal/min (94.6 to 37,854 L/min). It can be used in wells from 25 to
800 ft (7.6 to 244 m) in depth and from 6 to 24 in (15.2 to 61 cm) in
diameter. Carson, 1
A simple type of vertical centrifugal pump having one or more stages or
bowls, which are supported from the motor head on the surface by means of
screwed or flanged column pipe sections, each usually 10 ft (3 m) long.
The line shafting from the motor to the impellers is sectional to
correspond with the column section, and may operate in a sectional
extra-heavy enclosing tube if oil is used as a lubricant, or may be
exposed to the water when the pump is built to be water-lubricated.
Pit and Quarry
a. Broadly, shaft winding from depths of about 3,000 ft (915 m) and deeper
(coal mining). In the case of shafts deeper than about 5,000 ft or 1.52 km
(gold and metal mining), two-stage hoisting may be used.
See also:winding
b. Hoisting from depths below 5,000 ft in one lift. Spalding
c. Deep hoisting.
Middle Lower Devonian. AGI
Ark. Coal more difficult to mine than the standard, and for which the
miners are paid an extra price. Fay
To burn; burst into flame; specif., to burn rapidly with a sudden
evolution of flame and vapor.
An explosively combustible mixture, as one containing niter.
Standard, 2
An explosive reaction such as a rapid combustion that moves through an
explosive material at a velocity less than the speed of sound in the
material. Atlas
The removal of loose dry particles by the wind, as along a sand-dune coast
or in a desert; a form of wind erosion. AGI
a. See:base plug
b. Sometimes used by petroleum drillers as a syn. for deflecting wedge.
Long
A class of devices intentionally placed in a borehole to change its
course. All such devices are basically long, tapered, concave metal plugs
that can be set at a predetermined point and bearing in a borehole to
deflect or change its course. Also called correcting wedge, deflecting
plug, deflection wedge, Hall-Rowe wedge, spade-end wedge, Thompson wedge.
See also:correcting wedge; wedge. Long
A change in the intended course of a borehole produced intentionally or
unintentionally by various conditions encountered in the drill hole or by
the operational characteristics of the drilling equipment used.
Syn:deviation
a. The angular change in the course of a borehole produced accidentally or
intentionally. Long
b. A vertical angle, measured in the vertical plane containing the flight
line, by which the datum of any model in a stereotriangulated strip
departs from the datum of the preceding model. AGI
c. A horizontal angle measured from the forward prolongation of the
preceding line to the following line; the angle between one survey line
and the extension of another survey line that meets it. A deflection angle
to the right is positive; one to the left is negative. AGI
A taper bit, generally a bullnose type, used to drill down past the
deflecting wedge when deflecting a borehole. Long
The load-indicating gage on a penetrometer, which is a soil-testing device
used to determine some of the load-bearing characteristics of silt and
sandy soils. See also:cone penetrator
See:base plug
Point of deflection on a refraction time-versus-distance graph separating
two segments that correspond to different wave paths.
Schieferdecker
A wedge-shaped tool inserted in a borehole to direct the bit along a
prescribed course. Also called whipstock (undesirable usage).
See also:deflecting wedge
An instrument for gaging any deflections of a structure. Hammond
A device across the path of a conveyor placed at the correct angle to
deflect objects or discharge bulk material. Also called a plow.