Tailgate Lock Valve - Wittke StarLight Maintenance Manual

U2
U1
Main relief
70
T
AILGATE
The tailgate locking mechanism is equipped with hydraulic
safety systems that prevent accidental unlocking of the tailgate
D2
during operation. One of the systems is the velocity fuse with
the "power bleed" and the other is the lock valve.
The spool inside the tailgate section of the valve is designed in
D1
such a way that it will allow pressure to pass through it each
time the pressure is building up in the hydraulic system (i.e.:
when the packer is working). The pressure "burst" goes to the
holding valve into port "D1" and then out to the cylinder by port
"U1". This will keep the tailgate cylinders pressurized and the
tailgate closed when packing material.
The velocity fuse, located on the valve, will make sure to drain
any slow moving oil coming from the piston side of the tailgate
Velocity
fuse
cylinders. Since the rod side is being pressurized with the
"Power bleed" system, the other side has to drain to avoid any
pressure build-up. The velocity fuse makes the piston side open
to tank when the oil is moving under 3 gallons per minute and
will shut when a flow signal is sent.
Note:Refer to the main hydraulic schematic.
Location:
The tailgate lock valve is located on the underside of the body,
near the tailgate.
L V
OCK ALVE
Part #: 90309