XCMG XDN450, Operation Manual, Page: 94 / 126

!
1
Hydraulic
pump
Damaged parts Replace parts
Parts wear, gap is too large, leakage is
serious
Repair or replace parts
The oil level is too low and the
hydraulic pump is empty
Supplement fluid
Insufficient sealing of suction pipe,
resulting in suction
Tighten joints, check tubing, strengthen
seals
Pressure oil pipeline is not tightly
sealed, causing leakage
Tighten joints, check tubing, strengthen
seals
2
Relief valve
Spring deformation or break Replace spring
Spool stuck in open position, unable to
build pressure
Sliding slide valve makes it flexible
Pole valve or steel ball and valve seat
closely
Replacement of poppet or steel ball,
with grinding seat
Damping hole plugging Cleaning orifice
Remote port to tank Cut off the oil circuit of the tank
3
The hydraulic cylinder communicates with the high
and low pressure chambers
Repair the piston and replace the seal
4
Some valve unloading in the system Identify unloading reasons and take
appropriate measures
5
Severe system leak Strengthen sealing to prevent leakage
6
Pressure gauge failure causes no pressure artifact Replace pressure gauge
7
Too low viscosity of oil, exacerbating system leakage Increase oil viscosity
8
Excessive temperature leads to reduces oil
viscosity Find out the cause of the heat, take
appropriate measures, or dissipa
73