An arrangement of idler rollers on a conveyor in which the top set is
mounted on vertical arms which pivot on spindles set low down on the frame
of the roller stool. This permits the entire carrier frame to lean forward
slightly in the direction of belt travel. In the event of the belt not
running true, the tilting idlers guide it back to its correct course
again. Nelson
A surveying instrument with sighting telescope so mounted that it can be
raised or lowered through a limited arc without impairing accuracy of
reading, though axis of rotation is not precisely horizontal. The bubble
tube is usually mounted alongside the telescope and is viewed from the
eyepiece and through an optical sighting arrangement, which either brings
opposite halves of the bubble image into coincidence or the end of the
bubble to a reference line. Pryor, 3; Mason
A concrete mixer with a rotating drum, which is tilted to discharge its
contents. Hammond
a. Any of the wooden props, posts, bars, collars, lagging, steel joists or
beams, etc., used to support mine workings. Fay
b. To set or place timbers in a mine. Fay
c. Applied to rough blocks of natural rock as it comes from a quarry
before being shaped into sharpening stones. Mersereau, 2
See:timberman
a. An appliance for withdrawing timber supports from wastes, e.g., a
sylvester. Nelson
b. A miner engaged in timber drawing. Nelson
c. See:timber puller
See:drawing timber
Stope in which square-set timbering and its variations are employed. As a
rule, the ground is broken by overhand methods, the face being advanced by
successive small excavations, each one timbered before the next is begun.
Higham
One who cuts, frames, and/or puts in place any of the timbers used in a
shaft, slope, mine, or tunnel. Also one who draws props, posts, etc.
Syn:timberman
See:timberman
a. The operation of setting timber supports in mine workings or shafts to
support the roof or the face of a tunnel during excavation and lining. The
term "support" would cover the setting of timber, steel, concrete, or
masonry supports. See also:setting; timber set; face timbering;
pin timbering. Nelson
b. Timber work taken collectively in a mine. Standard, 2
c. Protecting against falls of roof formation of a mine, by means of
horizontal timbers or caps extending across the passageway just under the
roof, the ends of such timbers resting upon the vertical timbers or posts.
Ricketts
d. Timber to support the roof or the face of a tunnel during excavation
and lining. Stauffer
An electrically driven machine to raise and hold timbers in place while
supporting posts are set after being cut to length by the machine's
power-driven saw.
A tunnel support consisting of a roof beam, or arch, and two posts.
Nichols, 1
A jack to raise and hold crossbars against the roof while props are being
set. Hess
a. In bituminous coal mining, a head timberman is a foreman who supervises
workers installing timbers in a mine to support the roof and walls of
haulageways, passageways, and the shaft. Also called timber boss; timber
foreman. DOT
b. A miner skilled in notching, erecting, and securing timbers set in mine
workings. The craft of the timberman is gradually becoming extinct with
the advent of power tools and steel as a support. Nelson
c. See:roof bolter; timberer.
In mining, a laborer who assists a timberman in erecting supports for the
roof of a mine, using posts, headers, cap pieces, and wedges. DOT
Broken timber forming roof of ore deposit being extracted by caving
methods such as top slicing. It separates the downward gravitating
overburden and rock strata from the ore. Pryor, 3
a. A laborer who delivers timber to the working place in a pitching or
inclined coal seam. Fay
b. See:pack builder
A method to assist timber preservation; e.g., creosoting.
See also:timber preservation
Any treatment of mine timber for the purpose of extending the useful life
of the timber. Various preservatives are used, such as creosote, zinc
chloride, sodium fluoride, and other chemicals.
See also:brush treatment; guniting; open-tank method; pressure process;
Bethell's process; timber pickling; seasoning timber. Lewis
a. A piece of equipment used in removing the supports or timbers in a
mine. A timber puller should be constructed so that the operator will be
under safe roof while drawing the timber. A sylvester is an example of
this type of equipment. Also called timber drawer. Kentucky
b. See:timber robber