SANY SY155U, Operation And Maintenance Manual, Page: 99 / 192

MACHINE OPERATION
4-31 SY155U Excavator OMM
Two Tracks Stuck
1. Position the boom and arm at an angle between 90°
and 110°.
2. Pivot the upper structure to position the boom over
the front of the machine.
3. Curl the bucket so that the back of the bucket
touches the ground.
4. Lower the boom to raise the front of the tracks.
5. Place cribbing under the track to provide a firm
surface as necessary.
6. Raise the boom to lower the tracks onto the cribbing.
7. Cut the bucket into the ground in front of the
machine. Retract the arm (as with normal
excavating) while driving the machine forward out of
the mud.
Recommended Operations
WARNING
• Contact the site supervisor before any digging to
make sure that all underground hazards have
been located. Failure to follow this warning could
result in death or serious injury.
• To avoid injury, never allow any personnel within
the work zone of the machine.
• Be aware of all crush points on the machine and
make sure all personnel keep clear of these areas
to prevent injury.
• To prevent injuries, avoid moving any travel
control lever or pedal to abruptly change the
direction of the machine, and avoid stopping the
machine suddenly by releasing the lever or pedal
while traveling at high speed.
NOTICE!
• Avoid sudden stops when lowering the boom.
Hydraulic shock can damage the hydraulic
system.
• Avoid extending the arm cylinder while in full
travel. This can damage the hydraulic cylinder.
• Do not allow the bucket to come in contact with
the tracks when excavating at an angle.
• Do not allow the boom or arm hydraulic
cylinder’s hoses to come into contact with the
ground.
The machine can be used for the following operations.
The scope of operation can also be expanded by using
various optional attachments.
Backhoe Operation
0000703
Figure 4-64
Backhoe operation is used for digging an area lower than
the machine. The digging range of the arm is between
30° and 45°. The angle may vary according to the digging
depth.
0000704
Figure 4-65
Maximum digging force can be obtained when the angle
between the boom and arm and the angle between the
bucket cylinder and the bucket linkage are both at 90°.