Daikin Super Unit SUT00S8007-30, Operation Manual

Page: 90 / 95

PIM00413
13-12
13.8
High-pressure Safety Valve Adjustment Procedure
In the following three conditions, please re-adjust the setting of the high-pressure safety valve, by referring to
“High-pressure Safety Valve Adjustment Procedure” described below.
1. Even if the hydraulic unit is used with the maximum pressure setting, the safety valve will not be activated
under normal pressure control (except for the transient period when the circuit is blocked due to stop of
the master machine hydraulic actuator). However, the safety valve set pressure will be lowered due to
long-term repeated operations and contaminants in the hydraulic oil. If the safety valve is activated even
with normal conditions, safety valve adjustment is required.
[Judgment criteria]

The hydraulic oil temperature rising time is shorter than before.

When the safety valve adjusting screw is turned in the tightening direction, the rpm indication in the
pressure hold status is lowered.
2. To minimize surge pressure that much exceeds a setting pressure, safety valve adjustment is required in
consideration of the withstand pressure of the hoses being used.
3. When the pressure set value is changed from the factory setting.
In order to suppress the surge pressure for protecting actuator and pressure gauge, it is recommended
that the pressure setting of the safety valve should be the following value showing in the table below.
●
Recommended safety valve setting pressure
Product type Pressure setting of high-pressure safety valve
SUT00S8007 / SUT10S8007
Maximum operating pr0.5MPa
(7.5MPa)
SUT00D8021 / SUT10D8021
SUT16D8021
Maximum operating pr2.0MPa
(22.6MPa)
[High-pressure Safety Valve Adjustment Procedure]
[1] Referring to the enlarged view of the high-pressure safety valve shown in the
next page, loosen the lock nut.
(M10 lock nut, Width across flats: 14 mm)
[2] According to the pressure adjusting screw length reference chart, determine the
screw length corresponding to a desired control pressure setting. The reference
chart is different depending on different model.Refer to the table below, and
refer to the reference chart in the next page.
(The adjustment screw tip has been chamfered in 7mm width.)
[3] Turn ON the hydraulic unit power supply, and select the setting mode through panel key operation. Then, set a
desired pressure.
[4] Select [n05] (rpm display) in the monitor mode through panel key operation to show the current rpm.
[5] Adjust the pressure adjusting screw length in the longitudinal direction, and find an activation starting point as
shown on the right.
[6] Turn the pressure adjusting screw 1/8 cycle clockwise from the activation starting point.
[7] Tighten the lock nut. The safety valve adjustment procedure is completed.
(When tightening the lock nut, be careful not to allow the adjusting screw to turn.)
rpm
Pressure adjusting screw length
Activation starting point