Large Cargo Vessels Research Articles

Lightweight Composites for Heavy-Duty Solutions

In various parts of the marine industry, composites (often referred to as fiberglass or FRP), are usually thought of suitable only for recreational boats and small cruisers. However, composites have been used for the Navy's 57m (188ft) coastal minehunters and 46 m–49 m (150 ft–161 ft) yachts in the U.S. and for larger minesweepers and patrol vesselsin the U.K. and Sweden. Ten years ago these vessels would have been at the upper limits of perceived size limitation for FRPs, but presuming limitations on the size of vessels using compositesas the primary structural material are premature. Composites are presently used for sections of large steel vessels, including nonpressure hull decking, nosesections, sails and diving planes for submarines, weapons enclosures and masts for destroyers, funnels on cruise ships and hatch covers for barges. Research is ongoing for use of composites in larger deckhouse sections for combatant and structural hull materials for 200 m (670 ft) fast freight vessels. Potential uses on large steel cargo and auxiliary vessels include bulbous bows, bow fairings, hatch covers, stern fairings, deck machinery enclosures, and nonstructural interiors. Composites have also been used as a complete hull restoration for a vintage steel yacht. This paper reviews current usage and explores future potential for the use of composites on larger vessels. Issues of damage tolerance, corrosion resistance, flammability, classification, and regulation are investigated. This paper does NOT present the highest level of technology in the composites industry. It is simply presented as a primer for those who normally work with steel and aluminum to think out of the metal box.

The performance of buffer bow structures against collision

In order to prevent a disastrous damage induced by collision accident which might cause cargo oil spill from a struck oil tanker, the double hull system in side hull of oil tanker has been recognized as an effective countermeasures. However, when considering that ocean-going vessels are increasing not only in size but also in speed, the threat of disastrous collision accident should be further mitigated also on the responsibility of striking ships. The concepts of buffer bow have been proposed supposing its installation to fast passenger ships in the late 1960s and to large cargo vessels equipped with bulbous bow in the 1990s. RR76 panel of Shipbuilding Research Association of Japan and Ship Research Institute have started, as a joint work, to study the necessary items for the buffer bow structure since 1998.SRI has conducted a series of crush test using three kinds of simplified scale models of the buffer bow. A simple analysis method has been developed to evaluate the crashworthiness of buffer bow structure and its accuracy has been verified by comparing the results with the test and FEM calculation as well. The paper describes the performance of the buffer bow focusing on the collapse mechanism and the P/δ relation, then demonstrates the effectiveness of the present analysis method.

Composites for Large Ships

Composites, frequently referred to as fiberglass or FRP, are usually thought of as the material of choice for recreational boats. Recently, though, composites have been used for 57.3 m (188 ft) mine hunters and a 49 m (161 ft) yacht. Ten years ago these FRP vessels would have been at the upper limits of perceived size limitations, but practical limitations on the size of vessels using composites as the primary structural material are premature due to continuing advances in the materials and processing technology. Composites are used for small sections of large steel vessels including non-pressure hull decking for submarines, weapons enclosures for destroyers, and funnels on cruise ships. Potential uses on large cargo vessels include bulbous bows, hatch covers, stern fairings, deck machinery enclosures and nonstructural interiors. This paper reviews current usage and explores future potential on the use of composites on larger vessels.

The impact of european overseas discoveries on ship design and construction during the sixteenth century

Long before the European “Age of Discovery” began, mariners were ranging the coasts and nearer reaches of the eastern Atlantic and the North Sea, and vessels capable of keeping the sea for more than a few days had been developed. This provided an adequate basis upon which ships for farther voyaging could evolve. The major changes for overseas travel were in size and rig, but also important was an eventual alteration in design incorporating the carrying capacity of large cargo vessels and the weatherly qualities (ability to sail to windward) and maneuverability of the smaller caravel. Increase in size was necessary to carry larger crews and supplies for their sustenance, larger cargoes, and materials for repair and replacement of ship’s gear, sails, and the like. After much experimentation with various combinations of lateen and square sails, the full-rigged ship with relatively small square sails on the foremast and mainmast became the standard, although the lateen was retained on the mizzen and any other masts stepped astern of it. Other changes in design accommodated the need for armament. The result, fully developed by the end of the sixteenth century, was the full-rigged galleon, and little in the way of substantive changes in design and rig occurred during the next several centuries.

Cancer mortality in U.S. counties with shipyard industries during World War II

Respiratory cancer mortality, 1950–1969, was consistently high in U.S. counties where shipyards were engaged in the construction and repair of large naval and cargo vessels during World War II. Over three-fourths of the shipyard counties had elevated rates (in comparison to rates in counties of similar population size in the same region of the country) for lung and laryngeal cancer among white males, with the excess particularly evident in the South. Mortality from lung cancer was high also among white females, and the rate of increase in both sexes was greater than recorded nationally. In addition, rates for oropharyngeal, esophageal, and gastric cancers tended to be elevated in the shipyard counties, but mortality from other tumors was roughly comparable to national levels. A causal relation to asbestos exposures in shipyards cannot be inferred from this correlational analysis, but the unusual mortality patterns underscore the need for broadly based analytic studies to evaluate the risk of cancer in persons with wartime shipyard employment.

Generation, distribution, and use of electricity on board ship

Brief consideration is given to the problems involved in the use of electricity on board merchant ships. The applications of electricity to warships, whilst very extensive, are considered to be outside the scope of the paper. The various systems of generation in use, and considerations governing their adoption in individual cases, are outlined. The nature and situation of the services comprising the load are discussed, with special reference to the electrical equipment of (1) a large turbo-electric liner, (2) a Diesel-propelled intermediate liner, (3) a Diesel-electric tug, and (4) a large cargo vessel carrying refrigerated cargo. Particular reference is made to the refrigeration equipment of vessel (4), on account of its importance, and of the advantages offered in this sphere by electrical operation. The present position of electric propulsion is discussed, together with the probable future developments in this field.