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track gage

a. The distance between the inside edges of installed railway rails.
BCI
b. The minimum track gage that should be used on a modern haulage system
is 3 ft 6 in (1.07 m). This gage has been established as a standard by the
American Mining Congress as a result of the consensus of opinion of mining
engineers and manufacturers in the United States. Wheeler, H.R.
c. See also:rail gage

track haulage

Movement or transportation of excavated or mined materials in cars or
trucks running on rails.

tracklaying tractor

A tractor moving on crawler tracks. Hammond

trackless mine

A mine with no rails. In such mines, rubber-tired vehicles operate
independently of tracks and are used for haulage and transport.
Stoces

trackless tunneling

A method of tunneling using loaders mounted on crawler tracks, and a
diesel- or battery-powered dump-truck haulage system.
See also:rubber-tired haulage

track-mounted

Referring to the operation of equipment on tracks, such as track-mounted
cutting machines, track-mounted loaders, etc. Jones, 1

track-moving machine operator

In metal mining, one who operates a machine that moves and lays track
mechanically in open pit mines, picking up a section of track and moving
and laying it in the desired position without having to detach rails from
ties. Also called track-laying machine operator.
Syn:hydraulic jack operator

track pin

A hinge pin connecting two sections or shoes of a crawler track.
Nichols, 1

track resistance

The total rolling friction of a train on straight level track. It is
generally taken as 30 lb per short ton weight (15 kg/t) of the train for
cars having plain bearings and 20 lb/st (10 kg/t) for cars with roller
bearings. These figures may be increased by 10 to 15 lb (5.0 to 7.5 kg) if
the track is in poor condition and may be less for track in excellent
condition. Lewis

track roller

In a crawler machine, the small wheels that are under the track frame and
that rest on the track. Also called truck rollers. Nichols, 1

track shifter

A machine or appliance used in shifting a railway track laterally. Also
the operator of such a device or machine. See also:shifter

track spike

A heavy steel nail of square section that is driven into a wooden sleeper
to hold a flanged rail. Hammond

track stones

See:track diamonds

track wheel

One of a set of small flanged steel wheels resting on a crawler track and
supporting a track frame. Nichols, 1

traction

a. The act of drawing a vehicle over a surface and the force exerted in so
doing. Traction is the friction developed between tracks or tires and the
surface of the ground on which they are moving. Carson, 1
b. The total amount of driving push of a vehicle on a given surface.
Nichols, 1

tractive efficiency

A measure of the proportion of the weight resting on tracks or drive
wheels that can be converted into vehicle movement. Nichols, 1

tractive effort

a. The effort exerted by a locomotive at the rim of its driving wheels; it
is a function of its weight, the nature of its tires, and the condition of
the track. It is equal to the weight of the locomotive times the adhesion
of the locomotive to the track. For steel wheels on clean dry track the
adhesion is 25%, and the tractive effort is therefore 500 lb/st of weight
(250 kg/t). For cast-iron wheels the adhesion is 20%. Lewis
b. The necessary drawbar pull plus the resistance of the locomotive
itself. Kentucky
c. See:tractive force

tractive force

a. The pull exerted by a haulage rope on the drawbar of a car to overcome
the frictional resistance of the car and the force of gravity acting on
it. Also, the force available at the wheels of a locomotive to move the
machine and its attached load. Syn:tractive effort
b. The pull that a locomotive is capable of producing at its drawbar.
Hammond
c. In hydraulics, drag or shear developed on the wetted area of a
streambed, acting in the direction of flow. As measured per unit of wetted
area, unit tractive force equals the specific weight of water times
hydraulic radius times slope of channel bed (Chow, 1957). AGI

tractive power

The weight of the vehicle multipled by the coefficient of traction; it is
the total pounds of pull that can be exerted before slippage occurs.
Carson, 1

tractive resistance

The resistance to motion due to friction per unit weight hauled.
Hammond

tractor

A self-propelled vehicle--which may be mounted on crawler tracks, on
wheels with large pneumatic tires, or on a mixture of both--intended for
moving itself and other vehicles. See also:wheeled tractor;
mine tractor. Hammond