Zoomlion QY30V, Manual

Page: 115 / 276

04-20 04-20
Operation – crane superstructure Operation – crane superstructure
In this case, the acoustic sound will be sent In this case, the acoustic sound will be sent out and only the crane movement “Spool up out and only the crane movement “Spool up
winches” is permitted. During commissioning and maintenance, activate the bypass key winches” is permitted. During commissioning and maintenance, activate the bypass key
switch on the control console to release the limitation. See Fig. 04 – 12. switch on the control console to release the limitation. See Fig. 04 – 12.
Ne Never use the byp ver use the bypassing “ assing “ hoist dow hoist dow n” n” switch in n switch in n ormal ope ormal operation! ration!
Fig. 04 – 12 Fig. 04 – 12
4.4 4.4.5 Hydraulic s .5 Hydraulic s afety devices afety devices
- - Re Relief lief valves valves in in hydraulic hydraulic system system
The relief valves in hydraulic system can prevent the pressure in the circuit from The relief valves in hydraulic system can prevent the pressure in the circuit from
excessively rising, thus avoid hydraulic pump and hydraulic motor from being excessively rising, thus avoid hydraulic pump and hydraulic motor from being
damaged and hydraulic system from being overloaded. damaged and hydraulic system from being overloaded.
- - Outrigger Outrigger locking locking device device
If the high-pressure oil pipe which is connected to vertical cylinder is damaged, the If the high-pressure oil pipe which is connected to vertical cylinder is damaged, the
two-way hydraulic lock in the outrigger hydraulic circuit can stop the pressure oil in two-way hydraulic lock in the outrigger hydraulic circuit can stop the pressure oil in
the two chambers of outrigger cylinder to prevent the outrigger from retracting or the two chambers of outrigger cylinder to prevent the outrigger from retracting or
extending inadvertently, and thus ensure the safe operation of the crane. extending inadvertently, and thus ensure the safe operation of the crane.
- - Locking Locking device device for for crane crane moveme movement nt ““ De Derrick rrick main main boom boom up” up”
If the high-pressure oil pipe in If the high-pressure oil pipe in the hydraulic circuit of derricking cylinder is damaged, the hydraulic circuit of derricking cylinder is damaged,
the balance valve in the hydraulic circuit can stop the hydraulic oil in the derricking the balance valve in the hydraulic circuit can stop the hydraulic oil in the derricking
cylinder piston side immediately to prevent the boom from falling down cylinder piston side immediately to prevent the boom from falling down
inadvertently, and thus ensure the safe operation of the crane. inadvertently, and thus ensure the safe operation of the crane.
- - Lock Lock ing ing device device for for crane crane movement movement ““ T Telescope elescope main main boom boom out” out”
If the high-pressure oil pipe in the hydraulic circuit of telescopic cylinder is If the high-pressure oil pipe in the hydraulic circuit of telescopic cylinder is
damaged, the balance valve in the hydraulic circuit can stop the hydraulic oil in the damaged, the balance valve in the hydraulic circuit can stop the hydraulic oil in the
telescopic cylinder piston side immediately to prevent the telescopic bo telescopic cylinder piston side immediately to prevent the telescopic boom sections om sections
from retracting inadvertently, and thus ensure the safe operation from retracting inadvertently, and thus ensure the safe operation of the crane. of the crane.
Warning Warning