Komatsu D475A-5E0 Operation & Maintenance Manual page 209

OPERATION OPERATION
Cross ripping
On jobsites with hard bedrock, for rocks and boulders which are
impossible to break or dig up with one ripping pass, perform the
second ripping pass at right angles to the first ripping direction.
At the edge of cliffs, where it is impossible to apply the ripper in
a cross direction, make the space between the shanks smaller
and perform ripping.
During the ripping operation, if there is any hard bedrock,
perform ripping in the opposite direction to the direction where
the ripper was applied. If it is still impossible to break up the
rock, break up the area around the bedrock a little at the time.
When performing concentrated ripping of hard bedrock, the
work efficiency is high if the ripper is applied to the whole of the
digging face.
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OPERATION OPERATION