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omputer-Aided Manufacturing In Small Shipyards "Small shipyards face a difficult task in effec- vely employing computers," concludes a recent Dudy entitled Computer Aided Manufacturing i Small Shipyards: A U.S. and U.K. Compara- ve Study. The study was jointly conducted by Richard jee Storch, associate professor, industrial engi- leering/shipbuilding, University of Washington Seattle) and William Hills, engineering design enter, University of Newcastle upon Tyne (En- gland), and presented at the National Shipbuild- ng Research Program (NSRP) 1993 Ship Produc- ion Symposium, held last month in Williamsburg, /a. Mr. Storch, who limited his study to a lumber of yards he could reach by car in the U.S. Morthwest—including Union Bay Shipbuilding, Tacoma Boat, Foss Shipyard, Marco and Marine Industries Northwest—and Mr. Hills found a great deal of similarity in the two countries' small yards. The yards examined by both scholars included companies generally employing fewer than 200 people. In total, eight U.S. and 12 U.K. yards were studied. Due to the small sample, the survey sought levels of technology and trends which were representative of current practice in this segment of the industry, focusing on the level of automation in three key areas: design, produc- tion management and administration. In general, the survey found that smaller shipyards have made only small capital invest- ments in computer hardware and software, with the primary investments in computer aided de- sign (CAD) systems and in simple software for word processing and accounting. Nearly all hard- ware is stand-alone personal computers (PCs), with little or no integration of computer-gener- ated information. Design In general, employees involved in CAD were the only ones with formal training on computers. Most small yards involved with new construction have some design capability, whereas repair yards had no in-house CAD capability, instead opting for external consultants based on need. A wide Richard Lee Storch (I.), of the University of Washington and William Hills of the University of Newcastle upon Tyne, presented a study entitled "Computer Aided Manufacturing in Small Ship- yards: A U.S. and U.K. Comparative Study," at the recent National Shipbuilding Research Program Symposium in Williamsburg, Va. variety of CAD software is employed, but if there were a "standard," it would be AutoCAD in the U.S., with SFOLDS, MAST and AutoSHIP com- mon in the U.K. Lofting practice in small yards varies widely, both between the small yards and as compared to large yard practice. Direct devel- opment of Numerical Control (NC) data is un- common. U.S. practice is moving quickly to the use of sub-contractors for the electronic develop- ment of NC data. The primary need is for good 3D hull definition, based on AutoCAD or other de- sign software outputs. There is also a need for small yards to establish better internal control of the parts generation process. Production Management Very little (less than 10 percent) use of produc- tion management software of any kind was found in the small shipyards in either country. Most systems are manual, and there is no apparent means of integrating any of these systems with each other or with design-generated information. There is also a lack of a repeatable product work breakdown structure (PWBS) or a build strat- egy. Administration Many of the small yards do employ comput- ers for typical administrative functions, includ- ing payroll and invoice/billing. They are stand- alone systems, with no interface with any other computer application in the shipyard. Overall, the survey concludes that the small yards have a shortfall in computer productivity because of: use of the systems for single-purpose activities; lack of an overall computer applica- tion strategy; lack of a manufacturing system capable of deriving maximum benefit from com- puter applications; a shortage of trained person- nel; and a lack of capital for investment. Retommended Computer Strategy As small yards need to evaluate the integra- tion of powerful CAD tools and the direct link of NC control to these tools based on cost effective- ness and market prospects, the thrust of the recommendation lies in the production manage- ment area. Effective computer (or manual) production management, which is the area cur- rently addressed the least in most small yards, is dependent on two prerequisites: adoption of a product work breakdown structure; and system (data) integration. A key benefit of the use of computers is the reuse of data. A second key to effective com- puter utilization is the transfer of data used (or created) by one function to another function. This leads to the need for integration of com- puter data and company functions which em- ploy the same data. The report concludes that small yards are not now capable of realizing benefits of advanced software packages. It suggest they first move to a more struc- tured shipbuilding system before attempting to employ and realize the benefits of Computer Integrated Manufacturing. TABLE 3 New Construction Activity For 1 983-1 992 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 POWER DRIVEN VESSELS Towboats 17 12 9 1 2 3 4 4 7 10 Tugboats 28 10 8 7 18 11 8 6 6 3 Offshore Supply Boats and 20 21 8 1 23 0 18 2 11 2 Crew Boats Fishing Vessels 24 24 20 21 30 23 15 9 4 15 Ferries, Passenger Vessels 9 24 22 20 17 24 27 17 14 12 Military Vessels 35 120 120 90 122 119 39 27 52 46 Other 107 139 113 99 136 57 85 25 28 29 RIVER BARGES Hoppers 429 LASH and SEABEE Barges 3 Tank Barges 25 Deck Barges 17 Machinery Barges and 7 other Work Barges Other 2 155 203 120 0 0 4 8 8 4 40 58 31 6 3 0 12 5 7 45 217 484 0 0 0 4 9 18 45 40 49 0 2 12 51 10 8 380 441 612 0 0 0 64 81 92 55 30 53 12 36 7 10 16 1 OFSHORE BARGES Dry Cargo Hopper and 9 2 1 0 3 3 7 8 1 5 Deck Barges 3 1 7 Tank Barges 2 1 2 5 6 2 10 Machinery Barges and 1 2 0 0 0 1 1 0 1 1 other Work Barges Other 5 5 5 0 0 0 11 1 1 3 Source:American Waterways Shipyard Conference December, 1993 59