The National Ship Building Research Program: Design for Zone Outfitting

Book excerpt: For ship design, organizing information system by system is effective for creative purposes and for soliciting owner and regulatory approvals. There was a time when the same organization of information was effective for specifying outfit work to be accomplished by referencing system arrangement drawings. However, the advent of welding revolutionized shipbuilding. Steel is now processed everywhere in accordance with variations of the Hull Block Construction Method (HBCM). Literally, hulls are constructed block by block just as the Egyptians built the pyramids. Because of the availability of blocks, production people shifted to preoutfitting by extracting bits of information from a number of system drawings in order to collect the information needed to install portions of various systems in a single block. Productivity is inherently limited because outfit design, material definition and material procurement are in accordance with a system-by-system strategy whereas outfitting work is in accordance with a conflicting zone-by-zone strategy, Thus, some shipbuilders extended the logic of HBCM to create the Zone Outfitting Method (ZOFM) and the Zone Painting Method (ZPTM). This forced their outfit designers to become product oriented, i.e., to produce drawings that define work packages by zones and that do not require further processing by production people. Significant differences from conventional design are: elimination of many expensive system arrangement drawings, and time consuming identification of outfit work packages by product asoects on composite drawings, material lists structured to match the outfit work packages, and in usage of terminology and organization of design phases.