are primarily used in switching operations. Generally used within a
plant area, they are also well suited for other types of industrial railcar-moving
applications. These vehicles are equipt with a set of both railwheels and roadwheels.
This allows the vehicle to travel along the rail lines as well as surface roads
and through fields. A front and rear hydraulically operated couplier allows for
separate push and pull operation. Working both coupliers together the vehicle can
push and pull railcars at the same time. All operating functions are controlled
from within the operator's cab much like an actual locomotive.
Railcar movers utilize a process called Weight Transfer to assist them in moving the
cars. By borrowing weight from the railcar itself added traction is shifted to the
vehicle, pushing it firmly down upon the rail line.
The key to moving railcars is Tractive Effort. This is the amount of effort required
to move one ton along a railway. To calculate the amount of Tractive Effort a given
railcar mover can produce simply add the weight of the vehicle itself to the amount
of weight being transfered from the railcar it is coupled to and then divide the
total by 0.33 (the Coefficient of Drag).
Once you have calculated the amount of Tractive Effort a Railcar mover produces you
can then determine the number of railcars (loaded or empty)it will be capable of
moving at one time. This calculation is effected by five factors, Basic Railroad
Resistance, Track Conditions, Weather, Degree of Curve in the track itself, and
Percentage of Grade along the rail line. All of these can be determined with a
Track Survey.
