Cylinder Performance Tests - Doosan DX140R Shop Manual

Cylinder Performance Tests

NOTE: All tests are performed with standard boom, arm and
bucket configuration. The bucket should be empty.
Boom Cylinders Test
The starting points for the test are with the boom and arm
extended away from the excavator, and the bucket curled
inward. The arm cylinder should be fully retracted; boom and
bucket cylinders must be extended. Test movement in both
directions, several times, and average results for both Standard
Mode and Power Mode.
Arm Cylinder Test
Start with the boom up and the arm cylinder fully retracted. Test
movement in both directions several times, between the "crowd"
and "dump" positions, and average the results of both tests, in
both standard and extra-duty power modes.
Bucket Cylinder Test
Start with the boom up and the teeth of the bucket hanging
vertically, 500 mm (1-1/2' - 2') above the ground. Dump and
crowd the bucket several times, and average results, for both
standard and extra-duty power modes.
Operation
Boom Up
Boom Down
Arm Dump
Arm Crowd
Bucket Dump
Bucket Crowd
Hydraulic Cylinder Natural Drop Test
To check boom and arm cylinder tightness against the specified
performance standard for new cylinders, put a full load of dirt in
the bucket and move the attachment cylinders so that the arm
cylinder is extended 20 - 50 mm (1" - 2") and boom cylinders are
retracted the same amount, 20 - 50 mm (1" - 2"). The top of the
bucket should be approximately 2 m (6' - 7') off the ground.
Shut down engine and measure cylinder drop after 5 minutes.
Bucket cylinder should not show more than 40 mm (1.57")
change, while the arm and boom cylinders should not fall more
than 10 mm (0.39").
Specification for DX140LCR
Standard Mode
2.9 - 3.7 sec
2.3 - 2.9 sec
1.9 - 2.5 sec
2.5 - 3.3 sec
2.0 - 2.6 sec
3.6 - 4.4 sec
Power Mode
2.6 - 3.4 sec
2.3 - 2.9 sec
1.7 - 2.3 sec
2.4 - 3.2 sec
1.8 - 2.4 sec
3.4 - 4.2 sec
SP002379
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