a. An old syn. for pitticite. See:pitticite
b. See:triplite
In order to allow for the friction of the skips on the guides and between
the air and the skips in the shaft and for other small losses, it is usual
to divide the total static torque at any point of the wind by 0.9 for a
new shaft with rope guides, or 0.85 for an old shaft with rigid guides.
This factor is generally referred to as pit efficiency.
Sinclair, 5
Bottom of a pit shaft from which the sky is visible. Pryor, 3
A barrier of coal left around a shaft to protect it from caving.
Fay
In bituminous coal mining, a foreman who is in immediate charge of all
mining operations in a strip mine. See also:pit boss
a. The framework carrying the pit pulley. See also:headframe
Fay
b. The framework in a coal mine shaft. Standard, 2
An iron column that guides the cage in a mine shaft. Standard, 2
In the iron and steel industry, a general term applied to workers who
perform varied duties around the processing furnaces. DOT
a. Landing stage at the top of a shaft. Pryor, 3
b. The top of a mine shaft including the buildings, roads, tracks, plant,
and machines around it. See also:pit brow
The total tonnage of raw coal produced at a colliery, as distinct from
saleable output. It is the tonnage of coal as weighed before it enters the
coal-preparation plant. See also:run-of-mine
Eng. See:pit bank
An open lamp worn on a miner's cap, as distinguished from a safety lamp.
Either the vertical or lateral extent to which the mining of a mineral
deposit by open pitting may be economically carried. The cost of removing
overburden or waste material versus the minable value of the ore so
exposed is usually the factor controlling the limits of a pit.
a. The worker who regularly examines the condition of mine infrastructure.
Nelson
b. A connecting rod, such as in the Blake type of jaw crusher; the
vertical member linking the eccentric shaft with the toggles between the
frame and the lower end of the movable jaw.
An arm having a limited movement around a pivot. Nichols, 1
Workers employed in shaft sinking or shaft inspection and repair.
CTD
Surface mining in which the material mined is removed from below the
surrounding land surface. AIME, 2
An instrument that consists essentially of two pitot tubes one of which is
turned upstream and the other downstream and that is used to record
autographically the velocity of a flowing liquid or gas.
Webster 3rd
When the Pitot tube and static tube are combined, they form the
Pitot-static tube, and as such they can be used as an anemometer. The
tubes are usually arranged concentrically. When they are connected to the
opposite sides of a manometer, the dynamic or velocity pressure will be
measured directly. Roberts, 1
Consists of two concentric tubes bent in an L shape. In operation, the
instrument is pointed in the direction of air flow: the inner tube, open
at the end directed upstream, measures total head, and the outer tube,
perforated with small openings transverse to the air flow, records static
head. Each tube is connected to a leg of a manometer, when reading
velocity head. Hartman, 1
A pony used for packing or haulage in a mine. Webster 3rd