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pull hole

In sublevel stoping, term applied to a raise along the haulage level put
up to the first sublevel. The raise is enlarged at the bottom into a
grizzly chamber immediately over the haulage level and at the top is
widened into a funnel-shaped opening. As ore is broken, it drops directly
into a pull hole. Lewis

pulling pillars

The common expression used for mining the coal in the pillars of a mine;
robbing pillars. See also:pulling stumps

pulling stumps

The process of taking out the pillars of a coal mine.
See also:pulling pillars

pull-over mill

A two-high mill in which a piece is rolled in one direction only, and
after traveling between the rolls has to be passed back over the top roll
for rerolling. Osborne

pull pin

A device for throwing mechanical parts in or out of gear, or for readily
shifting in or away from a fixed relative position. Crispin

pull rope

The rope that pulls a journey of loaded cars on a haulage plane; the rope
that pulls the loaded scoop or bucket in a scraper loader layout.
See also:tail rope

pull shovel

A shovel with a hinge- and stick-mounted bucket that digs while being
pulled inward. Nichols, 1

pullway

The path from the face to the loading point taken by the scraper of a
scraper loading unit. Jones, 1

pull wheel

A large driving wheel or sprocket. Nichols, 2

pulmonary dust

Dust harmful to the respiratory system, including: silica (quartz, chert);
silicates (asbestos, talc, mica, sillimanite); metal fumes (nearly all);
beryllium ore; tin ore; iron ores (some); carborundum; coal (anthracite,
bituminous). Syn:fibrogenic dust

pulp

a. A mixture of ground ore and water capable of flowing through suitably
graded channels as a fluid. Its dilution or consistency is specified
either as solid-liquid ratio (by weight) or as a percentage of solids (by
weight). Pryor, 2
b. Pac. Pulverized ore or coal mixed with water; also applied to dry,
crushed ore. See also:vacuum filter

pulp assay

Pac. The assay of samples taken from the pulp after or during crushing.

pulp balance

Balance that weighs ore or coal pulp in a container of known volume;
graduated to show pulp density directly. Pryor, 3

pulp climate

In mineral processing, the general physical and chemical conditions of a
pulp, in which the pH, added chemicals, solid-liquid ratio, temperature,
particle size range, and ionization of a flotation pulp are held within
controlled limits while a considerable number of associated factors of
less direct importance to the surface chemistry of the process are, at
best, only indirectly monitored. Pryor, 3

pulp density

a. In mineral processing, the amount of solids in a pulp, typically
ranging from 10% to 25%, by weight. It has a marked effect on the recovery
and grade of concentrate. Taggart, 1
b. The weight of a unit volume of pulp; e.g., if 1 cm3 of pulp
weighs 2.4 g, then the pulp density is 2.4 g/cm3 .
Newton, 1

pulp dilution

The ratio of water to solids by weight. It is expressed as a ratio; e.g.,
a pulp dilution of 3 to 1 means that a pulp contains 3 t of water for each
ton of solids. Newton, 1

pulpit

The special platform upon which the operator of a Bessemer converter
stands. Mersereau, 2

pulpit man

Person who operates the complex controls of a rolling mill, in which iron
and steel ingots or billets are rolled into shapes such as bars, T's,
rails, and sheets, by throwing the correct electric switches when signaled
or by personal observation. Also called: manipulator operator; mill
control operator. DOT

pulpstone

A very large grindstone employed in pulp mills for crushing or grinding
wood into fiber. Fay

pulsator

a. A motor-driven air compressor that supplies compressed air to an
electric channeler. It receives the exhaust from the channeling machine
cylinder and thus utilizes the pressure of the exhaust.
b. In mineral processing, a Harz-type jig. See also:Harz jig
Pryor, 3

pulsator jig

A gravity concentrator utilizing vertical pulsations in a hydraulic medium
to separate particles by specific gravity differences.