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stationary bar screen

A large-capacity screening or sorting appliance for coal or ore. It
consists of a series of heavy metal bars arranged side by side and spaced
at a definite distance apart. The bars are set at an angle so that
material delivered at the upper end will just slide, and chutes are
arranged to receive oversize at the lower end and undersize passing
between the bars. The stationary bar screen is still used at many small
mines. See also:Bradford breaker; resonance screen; screen.
Nelson

stationary block

The relatively undeformed rocks beneath the plane of an overthrust fault.
See also:autochthon

stationary dredge

a. A dredge that is not self-propelled, the dredged material from which is
discharged into either a hopper barge or a pipeline. Hammond
b. A fixed vessel with equipment for digging, washing, and concentrating
alluvial deposits. See also:dredge

stationary engine

An engine located on a fixed foundation, as distinguished from a portable
engine. Crispin

stationary equipment

Stationary equipment is installed in a given location and is not moved
from that location in performing its function. This includes equipment
such as substations, pumps, and storage-battery charging stations.

stationary grizzly

The simplest of all separating devices and the cheapest to install and
maintain. It consists of a series of fixed bars or rails spaced the
required distance apart in order that the "undersize" may drop through.
The use of a stationary grizzly is limited to coarse screening of dry
material (aperture 2 in or 5.1 cm and larger), although it is sometimes
used with openings as small as 3/4 in (1.9 cm), the efficiency dropping
off in proportion. It is not satisfactory for moist or sticky material.
Pit and Quarry

stationary inner-tube core barrel

See:rigid-type double-tube core barrel

stationary jaw

The fixed jaw of a safety clamp or wrench. Syn:stationary slip
CF:anvil

stationary mass

In some seismometers, a heavy weight, either suspended or supported, that,
because of inertia, tends to remain quiescent during an earthquake.
Syn:steady mass

stationary-piston drive sampler

A piston-type sampler in which the position of the piston relative to the
sample remains constant during the sampling operation. Long

stationary slip

See:stationary jaw

station foreman

In metal mining, a laborer who supervises the haulage and handling of ore,
timber, and mining supplies at a shaft station. DOT

stations

Permanently marked points on the centerline of a tunnel . These stations
may be outside of the tunnel and used for projecting the centerline into
the tunnel, or they may mark the centerline inside the tunnel.
Stauffer

station yards haul

Equals the number of cubic yards multiplied by the number of 100-ft
(30.5-m) stations through which it is moved. Nichols, 1

statistical uniformity

A term describing that variation in quality of materials of manufactured
goods that is stable and determinate, so that statistical analysis and
prediction can be applied to it. See also:representative sample;
level of control. Hammond

statistics

The collection, tabulation, and study of numerical facts and data. In
industry, statistics indicate trends that would be almost impossible to
establish by other means. The statistical method is useful in: (1)
estimating the real value of work done, goods, or machines in terms of
useful service and maintenance costs; and (2) estimating and forecasting
profits and markets. See also:parameter

stator

In a torque converter, a set of fixed vanes that change the direction of
flow of fluid entering the pump or the next stage turbine.
Nichols, 1

statuary marble

A fine-grained saccharoidal marble used by sculptors. The best qualities
are pure white and free from markings.

staurolite

A monoclinic mineral, Fe2 Al9 Si4 O22 (OH)
2 ; pseudo-orthorhombic; Mohs hardness, 7.5; a common accessory in
medium-grade regional metamorphic rocks; may be of gem quality; cruciform
twins called fairy crosses. Syn:staurotide; cross-stone; grenatite;
fairy stone; lucky stone.

stauroscope

A type of polariscope used to determine the direction of light
polarization in a crystal for accurate measurement of angles of
extinction. See also:polariscope

staurotide

See:staurolite