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Original Date: 07/21/2003
Revision Date: 01/18/2007
Best Practice : Modular Unit Transportation
Electric Boat Corporation, Quonset Point Facility realized many benefits from implementing the Sea Shuttle Jack- Up Barge and the Scheuerle Transporters.
In 1974, Electric Boat Corporation, Quonset Point Facility (EBQP) began fabricating small unit packages (e.g., tanks, pipe packages, electrical components) for submarines and shipping them to the Electric Boat facility in Groton, Connecticut for final assembly and installation. Initially, EBQP shipped the packages by truck or small barge. EBQP began manufacturing internal submarine components as well as larger units (e.g., hull cylinders, decks) when the need to reduce manufacturing costs and relieve congestion at the Groton shipyard, where space and manpower were limited, was realized. These issues were addressed when EBQP planned to further expand its scope of work by outfitting the hull sections with internal structures and hardware prior to shipping them. However, EBQP’s existing crane and barge capabilities (300 metric tons) were insufficient to handle the weight of outfitted hull sections.
In the early 1980s, Electric Boat Corporation (EBC) acquired a Sea Shuttle Jack-Up Barge, as show in Figure 2-6, and modified its Quonset Point and Groton facilities for compatibility. This 75' x 195' barge has a dead weight capacity of 2,200 tons and features drive-on capabilities for loading and unloading. To stabilize itself, the barge extends its three legs into the water and onto a concrete pad at the dock. The legs also lift the barge out of the water until the deck is level with the dock. In conjunction with the barge, EBC purchased two Scheuerle Transporters (Figure 2-7), each with a 790-ton capacity for drive-on capabilities. These transporters can also be used in tandem to move up to 1,580 tons onto the barge.
EBQP teamed with Newport News Shipbuilding (NNS) to jointly build the Virginia Class new attack submarines. Under this arrangement, each shipyard takes the lead on constructing certain sections of the submarine, with both facilities sharing the final assembly responsibilities. Since large sections will need to be shipped between their sites, EBQP and NNS developed a transportation plan based on EBC's technique for shipping from Quonset Point to the Groton facility. To implement this plan, NNS constructed a docking facility, and EBQP upgraded the Sea Shuttle Jack-Up barge to U.S. Coast Guard standards for open ocean use.
EBQP realized many benefits from implementing the Sea Shuttle Jack-Up Barge and the Scheuerle Transporters. Since the mid-1970s, the company has increased its weight capacities to support new construction requirements. An increase from about 300 tons to 3,000 tons for barge shipping and transporter movement has been developed during this period. Loading and unloading procedures have been simplified, and the number of trips made by the barge was reduced. By being able to transport outfitted hull sections to another site, EBQP also shortened its production cycle and realized significant cost savings. The ability to outfit hull sections prior to assembly is a major benefit, due to reduced expenses compared to the cost of on-ship outfitting.
EBQP is continuously improving module transportation, which is based on their lessons-learned program. The company developed an environmental enclosure for shipping weather sensitive modules across the open ocean. EBQP and the Groton facility are currently using computer simulation to study module movements.
Figure 2-6. Sea Shuttle Jack-Up Barge
Figure 2-7. Scheuerle Transporter
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