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bottom-emptying skip

A skip equipped with a bottom discharge gate. Sinclair, 5

bottom equipment

a. The tools or equipment attached to the lower end of a drill string and
normally used at or near the bottom of a borehole. Also, the nondrilling
equipment placed and operated at or near the bottom of a borehole, such as
a pump unit or strainer. Long
b. Mine equipment used solely for work at the mine bottom, such as rotary
dump and switch motor (if used to spot cars in rotary dump).

bottom filler

A worker who fills a barrow with ore, coke, or stone, weighs it, and then
places it on the cage or elevator to be hoisted to the top of the furnace.
Fay

bottom gate

The gate road at the lower end of an inclined coal face.
See also:main gate; tailgate; top gate. Nelson

bottom heading

a. Method of excavating tunnels, drifts, or other mine openings. The
bottom heading, which may be either driven in successive stages or holed
through, is subsequently enlarged by excavating the top section.
Fraenkel
b. Overhand bench.

bottom hole

A point at, or near, the bottom of a borehole. Long

bottom-hole pressure

a. The load, expressed in pounds or tons, applied to a bit or other
cutting tool while drilling. Long
b. The pressure, expressed in pounds per square inch, produced at the
bottom of a borehole by the weight of the column of circulation or other
liquid in a borehole. Long
c. The pressure, expressed in pounds per square inch, exerted by gas or
liquids ejected from the rocks at or near the bottom of a drill hole.
Long
d. Pressure measured in a well opposite the producing formation. If the
well is flowing, the flowing bottom-hole pressure will be obtained; if the
well is not producing and has not been producing for a sufficient time,
the pressure will be the fully built-up, or static, bottom-hole pressure.
CF:ground pressure

bottom-hole temperature

The temperature of the fluid at or near the bottom of a borehole;
significantly lower than the temperature of the formation if borehole
fluids have been circulated recently or are being produced with expansion
into the well bore. Long

bottoming

The downward pinching-out or termination of an orebody, either
structurally or by economic grade. See also:bottom

bottom lift

a. The lowest or deepest lift or level of a mine. Zern
b. The deepest columns of a pump. Zern
c. The deepest lift of a mining pump, or the lowest pump. Fay

bottom loading belt

A bottom belt conveyor. Nelson

bottom maker

A laborer who relines bottoms of ingot soaking pits with coke dust to
retard formation of oxide scale on hot ingots. DOT

bottom pillar

A large block of solid coal left unworked around the shaft.
See also:shaft pillar

bottom-pour ingot assembly

One comprising hot tops, wood blocks, ingot mold, mold stool, lateral
outlet bricks, lateral bricks, king brick, fountain bricks, funnel brick,
and suitable metal supporting devices.

bottom-pour ladle

A ladle poured through a refractory nozzle in the bottom.

bottom rock

See:bedrock

bottoms

a. Used in connection with the Orford process for separating nickel and
copper as sulfides. When the mixed sulfides are fused with sodium sulfide,
the nickel sulfide separates to the bottom. See also:tile copper
CTD
b. The material drawn off from the bottom of a tower or still. Any residue
accumulating in the bottom of a process vessel.

bottom sample

A sample obtained by collecting a portion of material on the bottom of a
container or pipeline. Bennett

bottom sampler

One of various types of apparatus capable of piercing the sea bottom and
retaining a sample of the deposit when brought to the surface. CTD

bottom sheets

The steel plates forming the bottom of an oil still or a steam boiler.
Hess

bottom subsidence

See:subsidence