Hydraulic
System
The STC 80 is designed for use with an open center
hydraulic system when equipped as standard. The system
requires an approximate 16 horsepower to supply 10
gallons per minute and 2400 PSI. Power supply is generally
a direct mounted pump and PTO for truck chassis applications,
however other power supplies can be utilized. Crane
utilizes a four section, stackable, electric solenoid
operated directional control valve with a 25 foot
hard wired pendant control. A pressure relief is not
supplied. In instances where a relief cannot be incorporated
into other hydraulic system components, the optional
inline relief should be ordered.
Holding Valves
The base (extension) end of boom lift and extension
cylinders are equipped with pilot operated counterbalance
valves built into the cylinder. The counterbalance
valve provides protection from boom collapse in the
event of a hydraulic system failure or hose break.
In addition, the counterbalance valves smooth lowering
of the boom under load and also act as a thermal relief
to prevent excessive pressure build up due to thermal
expansion of the hydraulic oil.
Winch System
The winch is powered by a low-speed high-torque hydraulic
motor through a 38:1 ratio worm gear with an automatic
mechanical brake for load holding. Winch system is
equipped with 75' of 3/8" diameter wire rope of 6
x 25 construction. A ball bearing swivel hook is provided
for single line applications and a 2-part line block
is provided. Overhaul weights may be optionally supplied.
Rotation System
Rotation is accomplished by a turntable bearing, driven
by a lowspeed high-torque motor through a planetary
reduction gearbox. The drive incorporates a spring
applied, hydraulically released brake to lock the
system when not functioning. A mounted valve block
controls brake release and reset, and also provides
counterbalance valves to control smoothing of rotation
operation and prevent over-running loads when the
crane is rotated on an incline. Continuous rotation
provides efficient boom positioning.
Overload Protection
An active overload protection system is standard.
The system senses overload conditions and prevents
operation of boom extend and winch raise functions
in the event of an overload. Boom retract and winch
lower functions remain operational and allow crane
operation to alleviate the overload condition. When
systems are within rating limits the system will automatically
reset to normal operation.
Controls
Equipped as standard, control of the crane is provided
by a hard wired remote pendant providing on-off operation
of crane functions. Switches provided are military
spec sealed toggle, capable of reliable operation
in harsh operating environments which may be encountered.
Optional Equipment
Electro-Hydraulic Flow Control
System provides an electrically controlled
variable flow control valve which is operated at the
remote control pendant. The valve will allow control
of the oil volume supplied to the crane directional
valve and therefore will control the crane function
operating speeds. This system uses the same control
switches as the standard on-off control in conjunction
with a variable controller to regulate crane function
speeds.
Control Pendants
The standard remote pendant can be equipped with a
rotary actuator for control of electro-hydraulic flow
control system described above. A hard wired pendant
may be optionally supplied which uses an index finger
trigger actuator for true one hand control of all
crane functions and function operating speeds. A radio
remote control is also available which provides operation
of the crane without wired cables and allows complete
freedom of movement. The unit is FCC approved and
uses a multiple coding system to eliminate any possibility
of accidental operation. The radio remote may be equipped
for on-off or remote speed control operation.
Stabilizers
Stabilizer systems can be provided in manual or hydraulic
versions. A standard configuration is available or
a custom design can be provided for specific requirements.
Winch Options
Optional worm gear or planetary winches can be supplied
in single speed or two speed versions which can provide
line speeds of more than 100 feet per minute single
line, using hydraulic flows recommended for standard
cranes.
Other Options
A variety of other equipment
accessories and options can
be provided to meet the needs of specific applications.
Special equipment includes lifting hooks, flow adjusters
to allow user changeable selection of maximum crane
function speeds, inline relief valves, pallet forks,
grapples and other items too numerous to mention.
Please contact us for evaluation of any special requirements
you may have. |
Service
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