TM 5-3810-307-10
(3)
Swing Brake. The swing brake assembly consists of a brake assembly
mounted on the swing gearbox. The swing brake is hydraulically controlled
by the operator from the superstructure cab through use of the SWING
BRAKE ON/OFF selector switch which electrically positions the swing brake
control valve, and by the swing brake foot pedal when the SWING BRAKE
ON/OFF selector switch is in the OFF position.
(4)
Mechanical Swing Locks.
(a)
Swing Lock Pin. A pin-type swing lock that consists of a rounded pin
which engages a welded retainer to lock the turntable with the boom straight
over the front or rear of the carrier. The swing lock pin is operated using the
SWING LOCK Pin Control Lever (49, Figure 5-2).
(b)
Positive Swing Lock. A gear-type swing lock that consists of a lock
assembly with teeth that meshes with the swing gear teeth to lock the
turntable with the boom at any point along the 360 of rotation of the swing
gear. The positive swing lock is operated using the Positive Swing Lock
Handle (6, Figure 5-2).
l.
Boom Assembly. The boom is a three section, 27 to 70 ft (8.2 to 21.3 m) cable
extended boom.
The boom is trapezoidal in design and utilizes one 5.5 in. (13.9 cm) telescope
cylinder. The telescoping sections are supported on graphite impregnated nylatron
wear pads. Adjustable side wear pads prevent metal to metal contact between the
sections. The boom nose consists of three sheaves mounted on heavy duty,
tapered roller bearings and utilizes pin-type guards to allow easy reeving. The
boom features a mechanical boom angle indicator mounted on the left-rear side of
the boom.
m.
Main Hoist, Superstructure. The main hoist provides power and speed for load
raising and lowering operations utilizing the main hook block. A vane-type hydraulic
motor drives the hoist drum by means of a planetary gear reduction system. A
metallic disc brake is also an integral part of the hoist assembly. An indication of
hoist drum rotation is provided by an electronic pulse generator attached to the hoist
with a pulsating indicator in the boom LIFT/MAIN hoist control lever (8, Figure 5-2) in
the cab. The pulsation rate felt by the operator is proportional to the hoist speed.
n.
Auxiliary Hoist, Superstructure. The auxiliary hoist provides power and speed for
all operations requiring an auxiliary hook such as when the pile driver is attached to
the crane. Since the hoist is identical to the main hoist, it can perform all main hoist
operations. A vane-type hydraulic motor drives the hoist drum by means of a
planetary gear reduction system. A metallic disc brake is also an integral part of the
hoist assembly. The auxiliary hoist indicator also provides hoist drum rotation
information to the operator via a pulsating indicator in the boom SWING/AUXiliary
hoist control lever (20, Figure 5-2) in the cab.
4-5
