Figure 11-15.
Push arm and trunnion.
Figure 11-16.Hydraulic pitch arm.
Pitch arms arc diagonal members between the push
arm and the top of the blade. They brace the blade
against loads above the push arms and provide a means
of regulating the blade pitch and tilt. The pitch arms may
be threaded or have a hydraulic cylinder, as shown in
figure 11-16. To pitch the blade forward, lengthen the
arms. The forward blade pitch is for dozing extremely
hard materials. Pitch the blade back by shortening the
pitch arms. The back blade pitched is good for leveling,
spreading, or cleaning of loose material without the
blade digging in. Tilting is done by shortening one arm
and lengthening the other.
STRAIGHT BLADE. The straight blade (fig.
11- 17) is ideal for general dozing when materials are to
Figure 11-17.-Straight blade.
11-7