A Productivity Evaluation and Improvement Methodology for Shipyards

Shipbuilding is a highly competitive sector and shipyards are high-cost investments. Shipyards require good management, where all effort is spent to produce a unique, built-to-order, usually high-technology and big-size product as an output over long periods of time. Productivity is an important performance measure during the production of such unique output. Each shipyard in the world has its own distinctive way of building ships, conditions, and facts due to internal and external factors. Building a ship in the shortest time while delivering her at the required quality and within budget is an important indication of shipyard productivity. Therefore, continuous efficiency, performance, productivity measurements, evaluations, and improvements are necessary and critical. Research on a method to calculate a dimensionless "Productivity Number" system to overview the productivity status by a shipyard's own throughout a total shipbuilding process was deemed helpful. Developing a novel method formed the research problem; a common application during ship production helped to formulate the research problem and led to a mathematical model that is based on a common application in ship design. Sixty-two references and 21 methods on the measurement and evaluation of total shipbuilding process and shipyard productivity were found during the literature review. Only three of these methods, the Compensated Gross Tonnage (CGT), Data Envelopment Analysis (DEA), and Shipyard Productivity Prediction Equation (SPPE) based evaluations were put in use by some shipyards and by the academicians. About 500 factors were reviewed in the literature that affect shipbuilding in terms of production, infrastructure, engineering, management, and workforce. Among these factors, 185 were identified as having an important impact on the shipbuilding time schedule from the start of contracting works until the delivery of the ship. This study referenced these 185 factors as distributed among major ship production stages, shipbuilding management, and ship design works, all with unique importance, magnitude, and timing. Forty-two shipyards all around the world were applied for a comprehensive survey and surveys at two shipyards were realized. This was complemented by a survey with 26 experts with experience in shipbuilding, acting as the employees of two other hypothetical shipyards. Survey results provided shipyard-specific and generalized sector information in the utilization of the mathematical model. The model provided a reliable "Dimensionless Productivity Number" for a shipyard to evaluate the shipyard's overall productivity. Results presented a Dimensionless Productivity Number of a Shipyard (U), the improvement target number, and also the same for the processes, improvement needs, and possible effects of alternative decisions on improvements. The factors to be improved on each ship production stage, ship design, and management basis became visible. The chain reaction of any improvement act on the processes, positive or negative, became recognizable. This new mathematical and visual methodology assists in shipyard's top management to numerically see the status of the shipyard's own, different than benchmarking with other shipyards; shows the priority of the factors to be improved in ship production, ship design, and shipbuilding management processes. Application of this methodology will also lead to shorter shipbuilding periods. The method developed in this study is also expected to be found interesting by the academic field for further research and by other industrial sectors, especially those that manufacture unique products over extended periods of time.