Modularization of ship equipment in a complex vessel
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- Institutt for marin teknikk 
In early stages of design there are made big decisions under uncertainty. Ship design companies have to respond to a high number of tenders under strict time and resource-constraints in the process of selling designs. During the concept phase many of the most important decisions are made and approximately 80 % of assetshave to be fixed. Errors made at this stage are pretty cheap to address before signing contract, but far more expensive when discovered "down-stream" in the process. The Norwegian shipbuilders ability to respond to varying customer requirements is of essence in order to maintain their position in the market, opposed to the lean and low cost designs that are being designed and produced in the East. To manage these strict time- and resource-constraints, robust and quick design procedures are important.The research objective for the thesis is to identify and customize a method that canbe used to distinguish how variation in customer preferences a affects the physical division in the arrangement of a basis OSV design. A literature review focusing on theory and methods connecting customer requirements to design qualities identified a QFD-based method, "Kravhåndtering - Okt fleksibilitet ved tilpasset produktoppbygging", as fit for the purpose. A case study of a modern PSV is conducted to test the applicability and suggest changes to the method, and to answer the hypothesis: "QFD-based methods can be used to develop ship arrangements that increase the ships flexibility to variation in customer requirements". For the reference vessel the critical systems were defined and the power generation system was analyzed by the proposed method. The analysis of the system follow the methodology and consist of 6 steps: 1.Identifying requirements, 2.Strategies to fulfill requirements, 3.System decomposition, 4.Description of the connections in the system, 5.Description of the interconnectivity of the units by the product chart and 6.Identication of product strategies. The main finding was that in order to increase flexibility of the power generation system the engine foundation should be designed to accommodate different types and sizes of main engines. The method was developed in 1999, and the way of designing, procuring and constructing OSVs have changed since than. Earlier the yard designed, purchased and constructed systems that today are delivered by equipment suppliers. The case study revealed that the identified method is better suited for product design for suppliers than to identify changes in ship arrangement. However, the method generates much information about the systems, and by adopting some extra steps to the method (cataloging interfaces connected to varying customer requirements) the conclusion is that QFD-based methods can be used to develop ship arrangements that increase the flexibility to variation in customer requirements.