DOZERS AND ROLLERS
The dozer, technically known as a crawler tractor,
is used as follows: as a prime mover for pushing or
pulling loads, as a power unit for winch operations, or
as a dozer for earthwork operations and demolition
work. Rollers are compaction equipment used to
achieve mechanical compaction of earthwork materials
required by project specifications.
A variety of makes and models of dozers and rollers
are used by the Navy and the Naval Construction Force
(NCF). Each operator is responsible for reading the
operators manual to obtain detailed information about
each make and model. This chapter covers the general
characteristics and basic principles of dozer and roller
The dozer, commonly called a bulldozer, is a
crawler tractor on which a dozer blade has been
mounted (fig. 11- 1). Dozers are usually rated by size and
power. The pull developed at the drawbar is expressed
in pounds or as drawbar horsepower. The drawbar pull
is greatest in the lowest transmission gear range.
Although the specifications for dozers may vary among
different manufacturers, the maximum speeds are
seldom in excess of 8 mph.
The dozer is equipped with a diesel engine and is
supported on the ground by a track assembly. The track
assembly provides all-type-terrain versatility due to the
low ground bearing pressure at the track. This lower
ground bearing pressure, varying from 6 to 9 pounds per
square inch, has a distinct flotation advantage over
rubber-tired equipment ground bearing pressure that
varies from 25 to 35 pounds per square inch. Dozers are
capable of operating efficient y in muck or water as deep
as the height of the track for short periods of time. When
the dozer is properly waterproofed, it can operate in
fairly deep water.
When working in water that is deep enough
to reach the radiator, be sure to disconnect the
fan belt. If the fan blades hit the water while
under power, the y could bend or break off,
possibly causing damage to the radiator.
Additionally, exercise extreme caution to
ensure the engine does not overheat when the
fan or water pump belts are disconnected.