LiuGong CLG835H, Service Manual

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January 24, 2017 Testing and Adjustment
CLG835H Pressure test of work hydraulic system
2. Work system pressure adjustment:
Work system pressure components:
a. The outlet pressure of working pump at idling, namely as the spring setting pressure of working
pump flow control valve. The value of pressure measuring point 6 at working pump opening shall
be 2.6±0.1MPa\ 377±14.5psi by adjusting the flow control valve (refer to adjustment of working
pump);
b. The pressure of LS oil line relief valve of control valve. The value at pressure measuring point 6
shall be 19±0.3MPa\ 2755±43.5psi (after the setting value of flow control valve are met) by adjust-
ing LS relief valve (refer to adjustment for control valve).
If the above two places are set, the work system pressure is always less than 19±0.3MPa/ 2755±43.5psi,
which may be caused by the low cut-off pressure of working pump or low setting pressure of main safety
valve of control valve. Refer to Inspection and adjustment of cut-off pressure of working pump for cut-off
pressure adjustment of working pump, and refer to 6. Inspection and adjustment of main safety valve
pressure of control valve for main safety valve pressure adjustment of control valve.
Note: If the cause that the work system pressure is always less than 19±0.3MPa/ 2755±43.5psi isn't
determined, adjust that according to the following order:
a. First set the pressures of LS relief valve of control valve and the cut-off and setting pressure of
working pump to maximum, and see the respective adjustment for specific operations;
b. Second adjust the setting pressure of main safety valve of control valve to 21±0.3MPa\
3045±43.5psi in sequence (refer to Adjustment and inspection of main safety valve pressure of
control valve), the cut-off pressure of working pump to 20±0.3MPa\ 2900±43.5psi (refer to
Adjustment of cut-off pressure of working pump), and the pressure of LS relief valve to
16.5±0.3MPa\ 2392.5±43.5psi. After the above each pressure meets the adjusted value, refer to
Inspection and adjustment for pressure of work hydraulic system to control the constant pressure
value of pressure gauge in pressure measuring point 6 as 19±0.3MPa\ 2755±43.5psi. Refer to the
following flow chart: