Designed esp. for use in mines, these signal lights at individual switches
immediately indicate to the motorman whether or not it is safe to proceed.
Green and amber lights work automatically with the movement of the
switches. May be used with locally controlled switches, or with those
operated by a central dispatcher. Best, 1
Skip used to bring mined material to the surface of a mine shaft;
manufactured in various sizes and designs for both vertical and incline
shafts, including tipover models and bottom door dump models.
Best, 1
The energy consumed in the ventilation system to overcome all flow head
losses. It includes all the decreases in total head (supplied from static
head) that occur between the entrance and discharge of the system.
Hartman, 2
A mine manager or group manager. Nelson
The official at a mine who periodically surveys the mine workings and
prepares plans for the manager. Formerly, the mine surveyor carried out
many of the duties now performed by the planning department.
See:surveyor; mine. Nelson
Tin obtained from veins or lodes, as distinguished from stream tin.
Gross tonnage of ore including waste and unpayable material.
Beerman
The sum of all energy losses in the ventilation system. Numerically, it is
the total of the mine static and velocity heads.
See also:total ventilating pressure; ventilating pressure.
Hartman, 2
One of a variety of track devices to provide maximum safety for haulage
trains in mines. Designed to be used in conjunction with switch signals,
these devices include electric switch throwers operated by hand
contractors on a copper plate, overhead hand controllers, remote control,
or trolley contractors. Other safety equipment includes mechanical
switches for gaseous or hot mines, derailing switches for trains out of
control, and automatic mine-door opening devices. Best, 1
A trackless, self-propelled vehicle used to transport equipment and
supplies and for general service work. See also:tractor
Properly weighing the financial considerations to place a present value on
mineral reserves. Nelson
The velocity head at the discharge of the ventilation system. Throughout
the system, the velocity head changes with each change in duct area or
number and is a function only of the velocity of airflow. It is not a head
loss. The velocity head for the system must technically be counted a loss,
because the kinetic energy of the air is discharged to the atmosphere and
wasted. Therefore, it must be considered a loss to the system in
determining overall energy loss. Hartman, 2
A motor-driven disk, propeller, or wheel for blowing (or exhausting) air
to provide ventilation of a mine. See also:ventilation
Syn:ventilating fan
mine ventilation auxiliary fan
A small fan installed underground for ventilating coal faces or hard rock
headings that are not adequately ventilated by the air current produced by
the mine-ventilation fan. An auxiliary fan is usually from 0.5 to 1.0 m in
diameter. It is driven by compressed air or electricity. The auxiliary fan
can be used to force or exhaust ventilate the workplace.
A machine possessing rotating air-moving blades to exhaust or push the air
volume necessary to ventilate mine workings. See also:aerofoil-vane fan;
axial-flow fan.
mine-ventilation fan characteristics
The behavior of a fan under various conditions cannot be expressed in
simple mathematics but may be shown graphically by suitable curves, known
as the fan's characteristic curves or characteristics. The curves of
interest are generally head versus air quantity, power versus air
quantity, and efficiency versus air quantity. Hartman, 2
An arrangement of connecting airways in a mine together with the pressure
sources and control devices that produce and govern airflow.
Hartman, 2
Water pumped from mines usually contains impurities, some of which are in
suspension, but the majority, which are soluble, cause the water to be
hard. The water often contains corrosive agents, such as acids or alkalis.
Cooper
See:wireman
Ancient subterranean passages or mine excavations. Standard, 2
Mixed clay and sand or rock. Arkell