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hydraulic discharge

The direct discharge of ground water from the zone of saturation, as via
springs, wells, or infiltration ditches or tunnels.

hydraulic dredge

a. A dredge consisting of a hull on which is mounted a suction pipe and
support, a pump with motors and controls, and a discharge line. Commonly
used in dredging canals and in providing fill for the creation of land in
near-shore or low-lying areas and in sand and gravel dredging operations.
Mero
b. A floating pump that sucks up a mixture of water and soil, and usually
discharges it on land through pipes. Nichols, 1

hydraulic dredger

A suction dredger. CTD

hydraulic drill

A hand-held or machine-mounted rotary drill for boring shot-firing holes
in coal or rock and operated by hydraulic fluid. The drill outfit includes
a skid-mounted powerpack comprising a 5-hp (3.73-kW) flameproof electric
motor, pump, and tank. The coal drill weighs about 32 lb (14.5 kg).
Nelson

hydraulic elevator

An arrangement for lifting gravel and sand up to the drainage level. A jet
of water is used to create a powerful suction in a hopper, and the water
and gravel are carried up a pipeline and then run down the sluice boxes.
This appliance was widely used in various goldfields toward the end of the
19th century. Nelson

hydraulic excavation

Excavation by means of a high-pressure jet of water, the resulting
waterborne excavated material being conducted through flumes to the
desired dumping point. Hammond

hydraulic extraction

A term that has been given to the processes of excavating and transporting
coal or other material by water energy. Also called hydroextraction or
hydraulic mining. See also:hydromechanization

hydraulic feed

A method of imparting longitudinal movement to the drill rods on a diamond
or other rotary-type drill by a hydraulic mechanism instead of
mechanically by gearing. Long

hydraulic fill

Waste material transported underground and flushed into place by use of
water. Syn:mine fill

hydraulic-fill dam

A dam composed of earth, sand, gravel, etc., sluiced into place; generally
the fines are washed toward the center for greater imperviousness.
Seelye, 1

hydraulic filling

Washing waste material, such as mill tailings and ground waste rock, into
stopes with water to prevent failure of rock walls and subsidence.
Problems involved in its use are stope preparation, choice and mixing of
material, its particle size distribution, wear on pipe, and removal of
water that transports the material into the mine. Compressed air may be
used to force the filling through pipes. Lewis

hydraulic fluid

A fluid supplied for use in hydraulic systems. Low viscosity, low rate of
change of viscosity with temperature, and low pour point are desirable
characteristics. Hydraulic fluids may be of petroleum or nonpetroleum
origin. Hammond

hydraulic fluid coupling

A hydraulic fluid coupling transmits power from the driving member to the
driven member through oil. A rotating impeller attached to the drive shaft
throws oil directly against a turbine converter, which always delivers the
same torque as the engine or motor produces. Fluid couplings are
particularly advantageous in starting heavy loads since the motor or
engine is permitted to run at high efficient speeds while the coupling
output shaft gradually accelerates the load to running speed.
Pit and Quarry

hydraulic flume transport

The transport of coal, pulp, or mineral by the energy of flowing water in
semicircular or rectangular channels. The gradient should not be less than
3 degrees . Coal movement in flumes commences at a water velocity of about
3 ft/s (0.9 m/s), but in practice a velocity of at least 6 ft/s (1.8 m/s)
is arranged. See also:hydromechanization

hydraulic flushing

See:hydraulic stowing

hydraulic friction

The resistance to flow exerted on the perimeter or contact surface between
a stream and its containing conduit, due to the roughness characteristic
of the confining surface, which induces a loss of energy. Energy losses
arising from excessive turbulence, impact at obstructions, curves, eddies,
and pronounced channel changes are not ordinarily ascribed to hydraulic
friction. AGI

hydraulic giants

Used for working large placer deposits. Also called hydraulic monitors and
water cannons. Lewis

hydraulic gradeline

In a closed conduit, a line joining the elevations to which water could
stand in risers. In an open conduit, the hydraulic gradeline is the water
surface. Seelye, 1

hydraulic gradient

a. A line joining the points of highest elevation of water in a series of
vertical, open pipes rising from a pipeline in which water flows under
pressure. Webster 3rd
b. Loss of hydraulic head per unit distance of flow. ASCE
c. The slope of the hydraulic grade-line. The slope of the surface of
water flowing in an open conduit. Seelye, 1

hydraulic gravel-pump mining

Consists of the use of high-pressure water jets to disintegrate
ore-bearing ground, together with gravel pumps to elevate the spoil to a
treatment plant. Initial mining operations consist of the establishment of
the mine hole or paddock. This is achieved by sinking or cutting downwards
with monitors and removing the spoil by pumping, the pump being lowered as
the hole deepens. Mining

hydraulic hoisting

See:hydraulic transport