a. A conveyor comprising one or two endless linked chains with crossbars
or flights at intervals to move the coal or mineral. The loaded side of
the conveyor runs in a metal trough, while the empty side returns along
guides underneath. The material is transported on the conveyor partly by
riding on the chain and flights and partly by being scraped along in the
trough. The chain conveyor is widely used in coal mines, and capacities
range up to 100 st/h (90.7 t/h) with lengths of about 100 yd (91 m).
See also:armored flexible conveyor
b. See:drag-chain conveyor
A conveyor similar in design to those driven by ropes, the essential
difference being that the tension is taken by chains, either under or
alongside the carrying belt. Nelson
See:bucket elevator
See:mill feeder
An open guard of sheet metal, expanded metal, or similar construction
around a chain drive. Jackson, 1
a. A block and tackle in which chain is used instead of rope.
Crispin
b. See:chain block
The arrangement of block positions in a cutter chain so that bits inserted
in these blocks will occupy certain positions while cutting.
Jones, 1
Coal-cutting machine that cuts coal with a series of steel bits set in an
endless chain moved continuously in one direction either by an electric or
a compressed-air motor. These machines may be divided into four classes,
known as breast machines, shortwall machines, longwall machines, and
overcutting machines. Kiser
In bituminous coal mining, one who operates a chain-driven machine to
undercut coal preparatory to blasting it loose from the working face with
explosives. Also called chain driller. DOT
A pillar left to protect the gangway and airway, and extending parallel to
these passages.
For a roller chain, the distance in inches between the centers of adjacent
joint members. For a silent chain, the distance in inches between the
centers of the holes in a link plate. Jackson, 1
Main underground haulage road through which tubs are hauled by an endless
chain. Pryor, 3
A belt in which the carrying section may be made up of rubber or fabric,
woven metal, or other material and along each edge of which is fastened an
endless chain with a suitable attachment. The chains carry the driving
tension. The center part functions only as a loading supporting medium.
Silicate mineral with silica tetrahedra linked by shared oxygens into
infinite one-dimensional chains. Single chains characterize pyroxenes;
double chains characterize amphiboles; and wider chains grade toward sheet
structures.
A structure or texture found in a number of chromite occurrences,
consisting of a series of connected chromite crystals somewhat resembling
a chain. Schieferdecker
The simplest method of surveying, which has the advantage that the
equipment required is inexpensive and hard wearing. It is the ideal method
for small areas and has been employed successfully for large surveys.
Nevertheless, it has definite limitations when applied to surveys of
enclosed or built-up areas. Mason
An idler sprocket, or similar device, mounted on an adjustable bracket to
adjust the slack in a chain drive. See:takeup
The actual force existing at any point in a conveyor chain.
A conveyor using a driven endless chain or chains, equipped with flights
that operate in a trough and move material along the trough.