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79 - 5
Section E
Hydraulics
9803/6020
Section E
79 - 5
Issue 1
Hydraulic Rams
Fault Finding (cont’d)
Item Symptoms
Related Parts
Trouble
Treatment
4-3
Air remaining inside ram.
•
Bleed the air.
Operation is unsteady
For rams that do not have an air
bleeder, operate back and forth several
times at low pressure and low speed to
bleed the air. For rams with an air
bleeder, remove the load to reduce the
Air
pressure then loosen the air bleeder
and completely
bleed the air.
Note:
The ram may expand if it is
stopped suddenly. This is due to the
compression of the hydraulic oil. This
occurs especially with long stroke rams.
4
4-4
Pin bushing/pin
Gap between mounting and
Measure the pin and pin bushing and
Heavy shock
pin bushing is too large.
renew parts if measurements exceed
loading when
the specifications.
changing from
extension to
retraction
and back
Oil supply
Insufficient oil.
•
Add oil.
Pin bushing/pin
Scuffing at connecting part.
•
Replace with new part and add oil.
Note:
If left in the state where operation is poor, the ram will no longer move and other parts will be affected
adversely. Inspect early and carry out appropriate measures.
4-5
Noisy
operation
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