Types Of Bulldozers

2.  Bulldozer is a crawler(continuous tracked tractor)
equipped with a substantial metal plate used for cutting
and pushing large quantities of materials for relatively
short distances.

4.  Clear site of work.
 Leveling of land.
 Prepare roads on hilly as well as hard ground.
 Excavate the material and haul in between 100 meters
distance.
 Spreading earth fill.
 Backfilling trenches.
 Maintaining haul roads.

5.  Bulldozers might either be cable controlled or
hydraulically controlled.
 Depending upon mountings, bulldozers are classified
as:-
◦ CRAWLER MOUNTED BULLDOZERS
◦ WHEEL MOUNTED BULLDOZERS

7.  Greater attractive work delivery on soft grounds
 Ability to travel over
◦ muddy surfaces
◦ Rocky formations
◦ Rough surfaces
 Greater use versatility on job

9.  Higher travel speed from one job to another
 Elimination of hauling equipment to transfer the
bulldozer to the job
 Greater output when considerable travelling is
necessary
 Less operator fatigue
 Ability to travel over paved highways without
damaging the surface

10. Dozer blades usually are of three types:-
 Straight Blade (S-Blade)
 Universal Blade (U-Blade)
 S-U Combination Blade

11. S-Blade
It is short and has no lateral curves, no side wings and
can be used for fine grading.
U-Blade
It is tall with a high curvature and large side wings to
carry more material.
S-U Blade
It is shorter, has less curvature, and smaller side wings.
It is used to push piles of large rocks.

12. Depending upon the nature of blade:
 FRONT CASTING DOZER : Blade is fixed
perpendicular to direction of travel.
 ANGLE DOZER : Blade is fixed at an angle with
the direction of travel.
 TILT DOZER : Dozers are accompanied with ‘tilt
cylinders’ to vary the angle while moving.
 TREE DOZER : The bottom edge of the blade is
sharpened, e.g., to cut tree stumps.
 PUSH DOZER : Dozers required to push the earth.

15.  With suitable attachments, can be utilized to remove
trees, rocks, boulders etc.
 To increase the output, two dozers working side by side
with their blades in contact can be used.
 Can be used on wet ground and all types of weather
conditions.

16.  Efficiency of operator
 Nature of soil
 Topography of soil
 Efficiency of equipment (blade factor)
 Weather
 Size of condition of bulldozer
 Distance travelled

17.  Output of bulldozer measured in volume/hour
= loose volume handled per trip * S * 60/t *
efficiency
where,
S= Swell factor (Ratio of volume of original earth to
loose earth)
t= time required per trip in minutes
t= D/F + D/R + G

18.  Loose volume handled per trip =
Blade width X (Blade height)2 X (Blade factor)
 Blade size:
Width = 2 to 7.5 m
Height = 0.8 to 1.5 m
 Blade factor = 0.4 - 1.1