CHAPTER 2 BRIDGE CRANE SYSTEM
Section I. Description and data
Description. 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 (Figure 2-1)
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 on each ROWPU system; and an "I" beam rail system. The "I" beam rail
system, over which the cranes move, 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. Figure 2-2 provides a top-down view of the various equipment transport paths. The
bridge crane system installation is shown on drawings listed in Appendix A.
Capabilities. The bridge crane lifts and transports loads of up to 5 tons with the geared trolley hoist. Loads of 2
tons or less are lifted with the electric hoist when installed on the trolley hoist.
Limitations. Load limitations are set at loads of 5 tons or less for the bridge crane and 2 tons or less with the
electric hoist. Lifting slings, listed in paragraph 2-8.1, must be used to lift and transport such items as 155 kW
generators, ship auxiliary generator (SAG), ROWPU high-pressure (HP) pumps, media filters, and 55-gallon drums.
Performance characteristics. See manufacturers' service manuals in Appendix B.
a. Geared trolley hoist
Monogram Industries, Inc.
Chester Hoist Division
Low headroom with track
5 tons (10,000 lb)
b. Cable reel
Aero-Motive Manufacturing Co.
Roller outlet w/40 ft of 4 conductor #14 wire
Division of Jervis B. Webb Co.
Swinging w/hinge assemblies and tie rod
9 ft 2 in.