Handling equipment description. The handling equipment is used for lifting, transporting, and repositioning
equipment and materials onboard the barge. This system includes a bridge crane, bow crane, and void 4 trolley hoist.
The bridge crane is installed in the reverse osmosis water purification unit (ROWPU) space, bow crane on the forward
weatherdeck, and the trolley hoist in void 4 starboard. The bridge crane is used also to load and offload supplies and
equipment through the deckhouse starboard sliding door. The bow crane is used primarily to unload and load the
workboat from the deckhouse top and to load and unload the shore winch from its carrying position in front of the bow
crane on the forward weatherdeck. The trolley hoist is used to lift or reposition equipment in void 4.
Bridge crane system. The bridge crane system, in the ROWPU space, lifts and transports heavy equipment
and materials, such as diesel generators and 55-gallon drums. The bridge crane is also used for loading and unloading
equipment and materials through the deckhouse starboard sliding door. Bridge crane major components include: two 5-
ton capacity, motor-driven, overhead cranes with end truck assemblies; a manual, chain-operated, geared trolley hoist; a
cable reel located midway in each system and an "I" beam rail system. The "I' beam rail system, which the cranes move
over, is suspended from the deckhouse structure by a series of support posts. Two crossover members located between
the port and starboard bridge cranes provide for transfer of the geared trolley hoist. A four-button, hand-held electrical
control is used for controlling fore and aft crane movement. Electric power is provided to the crane through a cable that
is extended or retracted by the cable reel as the crane moves forward or aft. Additionally, a 2-ton electric hoist provides
for lifting lighter loads. A jib rail provides a method for moving suspended loads through the barge sliding door. The
bridge crane system installation is shown on drawings listed in Appendix A.
Bow crane system. The bow crane is a hydraulically operated articulating boom crane with a maximum
outreach of approximately 47 feet. Maximum lift capacity at this extension is 2,425 pounds. Maximum lift is 41,895 at
an outreach of only 6 feet, 7 inches. The crane is corrosion-proof and suitable for operation in a marine environment.
The crane has five major assemblies: crane body, inner boom, outer boom, mounting base, and hydraulic control unit.
When not in daily use, bow crane must be placed in its traveling (stowed) configuration.
The crane body is a steel casting with the upper part being a closed welded box design through which hydraulic
hoses are routed to inner and outer boom actuating cylinders. Inner and outer boom assemblies are positioned, as
required, by extending or retracting hydraulic actuators. A winch assembly is mounted on top of the primary element of
the boom for retrieving loads of 10,000 pounds or less. For winch loads greater than 10,000 pounds, the sheave block
must be installed on the end of the outer boom.
Operator controls for the crane are on the forward side of the deckhouse top. They include five control levers for
controlling crane movement, a START/STOP control switch, and a key lock for the anti-2-block control system. The
START/STOP control switch, and a key lock for the anti-2-block control system. The START/STOP control switch and
anti-2-block key lock are in a watertight storage box aft of the crane control levers. Another START/STOP control switch,
primarily for emergency use, is on the weatherdeck forward bulkhead.
Hydraulic pressure for the bow crane is supplied by a hydraulic power unit in void 1 port. A 30 Hp electric motor
drives the pump to produce 3600 psi of hydraulic pressure. A motor controller in void 1, starts and stops the local unit
and supplies power to the two remote START/STOP control switches. The motor controller requires 440 Vac, 3 phase,
60 Hz power.
Void 4 Trolley Hoist. Void 4 trolley hoist in void 4 starboard is a low-headroom, manually-operated hoist. Major
components include an "I" beam suspended from the void 4 overhead structure, a manual hoist assembly, load chains, a
block hook, and a brake mechanism. The trolley hoist has a net weight of 230 pounds and a standard lift height of 8 feet.
The load chains measure approximately 9 feet 6 inches and require 41 pounds of pull to lift a full load. The hook
assembly has a diameter of 1 3/7 inches. The "I" beam measures approximately 6 inches in width.