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multiple-ply plate

Steel plate made up of thicknesses of other plates of steel or steel and
wrought iron welded together. Mersereau, 2

multiple recording groups

See:multiple detectors

multiple ribbon belt conveyor

A belt conveyor having a conveying surface of two or more spaced strands
of narrow flat belts.

multiple-row blasting

The drilling, charging, and firing of several rows of vertical holes along
a quarry or opencast face. The holes may be spaced in the square pattern
with delay detonators in the rows as well as row by row. The spacing of
the holes will vary according to their depth, diameter, and the type of
rock. See also:small-diameter blastholes

multiple-seam mining

Mining two or more seams of coal, frequently close together, that can be
mined profitably where mining one alone would not be profitable.
Coal Age, 3

multiple seismometers

See:bunched seismometers

multiple series

A method of wiring a large group of blasting charges by connecting small
groups in series and connecting these series in parallel.
Syn:parallel series

multiple shooting

The firing of an entire face at one time. The holes are connected in a
single series and all the holes shoot at the same instant.
Kentucky

multiple shot

See:battery of holes

multiple-shot blasting unit

A multiple-shot blasting unit is designed for firing simultaneous
explosive charges in mines, quarries, and tunnels. Syn:blasting unit

multiple shotholes

Two or more shotholes that are shot almost simultaneously. They are so
spaced as to minimize near-surface interferences that mask desired signals
if only one shothole is used. AGI

multiple-shot instrument

A borehole-survey instrument capable of taking and recording a series of
inclination and bearing readings on a single trip into a borehole.
CF:single-shot instrument

multiple-shot survey

A borehole survey using a multiple-shot instrument. Long

multiple sill

A sill made up of two or more intrusions composed of the same kind of
igneous rock. Billings

multiple-speed floating control system

As used in flotation, a form of floating control system in which the
manipulated variable may change at two or more rates each corresponding to
a definite range of values of the actuating signal. Fuerstenau

multiple splitting

The parting or separation of a thick seam into more than two layers of
coal. See also:simple split seam

multiple-strand chain

A roller chain made up of two or more strands assembled as a single
structure on pins extending through the entire assembly.
Jackson, 1

multiple-strand conveyor

a. Any conveyor which employs two or more spaced strands of chain, belts,
or cords as the load-supporting medium.
b. Any conveyor in which two or more strands are used as the propelling
medium connecting pans, pallets, etc.

multiple-strand rope

A wire rope designed to obviate spinning due to untwisting. It is formed
by a series of layers of strands built around a center fiber core. Each
layer of strands is given a lay opposite to that on which it is built,
each layer thus tending to impart its own twist that is cancelled by the
next layer. Therefore, this rope can be used for sinking or where a free
load is to be lifted. The stretch with a multiple strand rope is not so
great as with round strand and flattened strand ropes.
See also:multistrand rope; wire rope. Nelson

multiple twin

See:repeated twinning

multiple-vent basalt

See:shield basalt