Sinoboom GTJZ0612E, Maintenance Manual

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MAINTENANCE PROCEDURES
GTJZ0612E&0812E&1012E&1212E Maintenance Manual 5-7 © Jul.2020
Regulating the Platform Lifting
Overflow Valve
NOTICE
Be sure the hydraulic tank is full of oil.
1. Place the maximum rated load on the platform and
ensure it is placed properly. (For details, see
Speci-
fication, page 1-1 .)
2. Switch the key switch to the ground controller and
pull the emergency stop button on the ground con-
troller and platform control box out to the “ON”
position.
3. Lock the lifting overflow valve with a wrench and re-
move the nuts.
4. While turning the platform lifting switch, turn the in-
ner hexagon socket clockwise until the platform
rises to the highest position.
5. Lower the platform completely.
6. Add the weight 1.2 times of the rated load on the
platform and properly place it.
7. Try to lift the platform, the platform cannot be lifted.
8. If the platform is still lifting, regulate the inner hexa-
gon in the counterclockwise direction till the plat-
form cannot be lifted.
9. Properly install the nuts.
10. Remove the weight from the platform.
11. Lift the platform to the highest position. If there is an
air suction of the pump or if the platform cannot be
lifted to the highest position, add hydraulic oil to the
tank until the pump properly operates. Do not allow
the oil to overflow from the oil tank.
NOTICE
Do not allow the machine to operate if there is pump
suction air. Damage to the pump could occur.
Adjusting the Steering Overflow Valve
NOTICE
Be sure the hydraulic tank is full of oil.
1. Locate the steering overflow valve on the valve
block. (For details, see
Installing the Cartridge
Valve, page 5-6 .)
2. Connect a pressure gauge 0 - 40 MPa (0 - 5,800
psi) to the system pressure measuring port.
3. Remove the platform controller from the platform.
Operate the controller from the ground.
4. Switch the key switch to the platform controller. Pull
the emergency stop button on the ground controller
and the platform control box out to the “ON”
position.
5. Holding the platform controller, press and hold the
turn right button to bring the wheel to the right limit
position and maintain stability, and record the pres-
sure on the pressure gauge. (Specified pressure
values are available for reference
Power System
Specifications, page 1-7 )
6. Holding the platform controller, press and hold the
turn leftt button to bring the wheel to the left limit po-
sition and maintain stability, and record the pressure
on the pressure gauge. (Specified pressure values
are available for reference
Power System Specifi-
cations, page 1-7 )
7. If the measured values do not match the specified
values, steps 8
～ 12 are performed.
8. Push in the emergency stop button.
9. Loosen the steering overflow valve nut.
10. Turn the hexagon socket clockwise to increase the
pressure and counterclockwise to reduce the
pressure.
NOTICE
The pressure valve must not exceed the specified
value. Damage to the hydraulic system could
occur.
11. Tighten the steering overflow valve nut.
12. Repeat steps 5 and 6 to determine the pressure
values.
13. Remove the pressure gauge.
Adjusting the Emergency Lowering
Handle
NOTICE
The platform must be empty to perform this test.
Adjust the emergency drop handle as follows:
1. Raise the platform 2.1 ～ 2.8 m(6.9 ～ 9.2 ft).
2. Engage the safety arm.
3. Lower the platform and support the scissors arm
with the safety arm.