Analysis And Optimization For The Influencing Factors Of Shipbuilding Schedule For30000DWT Multi-purpose Heavy-lift Vessel

Due to the restrictions of precision, difficulty and complexity of construction, shipbuilding schedule of special ships greatly restricted the market competitiveness of China’s shipbuilding industry. There were important theoretical significance and practical value for the resource integration of China’s shipbuilding industry, the overall upgrade of shipbuilding level and the improvement of competitiveness in the international market by In-depth analysis shipbuilding process of special ships, summarizing the influencing factors of shipbuilding schedule, identifying the main factors and taking countermeasures.Shipbuilding process of30000DWT multi-purpose heavy-lift vessel was described in detail based on the construction process of a ship, which includes design, steel materials processing, sub-section production, folding on berth, underwater outfitting and commissioning, sea trials and delivery of ship. In accordance with the construction characteristics of30000DWT multi-purpose heavy-lift vessel, i.e., the huge difficulty of hull assembly welding, the high accuracy requirements of folding, a large amount of outfitting in cargo hold and a large amount of equipments layout in a small machinery space, the influencing factors of shipbuilding schedule were summarized as shipyard internal factors which include the level of organization and management, technical factors, staff factors, reliability of equipments, management of positioning, emergency response mechanisms and the level of information technology, and shipyard external factors which include ship owners and classification societies, suppliers, natural factors and social factors. Based on AHP, combined the shipbuilding site engineering practical experience and expert advice, the weights of indices were determined and the total sequence was obtained. According to the results of total sequence, the main influencing factors of shipbuilding schedule include the staff factors, the management levels of positioning, the integrity of sub-section production, the management of suppliers, the readiness of production, the degree of accuracy control, the integrity of pre-outfitting, the reliability of equipments, ship owners and classification societies, the folding scope of sub-section and so on, which was quite consistent with on-site engineering practical experience.The results show that it was feasible to determine influencing factors of shipbuilding schedule and to determine the degree of the relative importance of various factors by employing AHP method. According to the results of total sequence determined by AHP, strengthening education, training, and management of shipyard employees, strengthening the management of suppliers, improving the management level of positioning, strengthening the integrity of sub-section production and pre-outfitting and strengthening the accuracy control are effective means to improve shipbuilding schedule of30000DWT mult-ipurpose heavy-lift vessel.