An experience of modularity through design

We aim to utilise the experiences of a marine industry-based design team to determine the need for research into a modular design methodology in an industrial environment. In order to achieve this we couple the outcome of a current design project with the findings of a recent literature survey with the objectives of firstly, clarifying why a methodology is required and, secondly, defining the key elements which the methodology would have to realise or address. The potential benefits of modularity have long been recognised in the shipbuilding industry. Many shipbuilders adopt a 'module' approach to ship construction whereby the ship structure is separated into a number of large structural 'blocks' to ease manufacture and manoeuvrability during construction. However, as understanding of the capabilities of modularity as a design tool develops there is increased interest in capitalising on the differing life phase benefits of modularity such as reduced design costs and time, increased ease of maintenance, upgrade, re-use, redesign and standardisation across individual products and product families. This is especially pertinent in naval shipbuilding where the maintenance of a class of ship requires that all previously designed ships in that class must be of similar outfitting and must be able to interface with the new ship, in terms of propulsion, weapons, communications and electronics, and thus often require some form of retrofit. Therefore, many shipbuilders are moving from viewing modularity as a purely 'manufacturing' principle to a design centred principle. However, as noted by Chang and Ward 'none of the design theories or tools in the mechanical world serves as an articulate procedure for designers to follow in practising modular design'. Thus, despite the identification of a need to introduce modular principles at an earlier stage than detail design and construction, there is little aid in the form of tools, techniques and methodologies for designers in practice

Estimation of ship construction costs

Thesis (S.M. in Ocean Systems Management)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.Includes bibliographical references (p. 105-107).Since the end of the Cold War naval procurement for the US Navy has seen a dramatic decrease. This decrease in defense spending has placed existing programs under more scrutiny than previous years. As a result there is less tolerance on the part of taxpayers and Congress for procurement cost growth. This Thesis attempts to examine the current method that the Navy conducts ship cost estimates and suggests changes in order to improve the confidence level and accuracy of the forecasts. An examination of how industry is conducting cost estimates was used as a comparison to the current Navy practices. Finally using only a weight based approach to ship cost estimating is insufficient. It is necessary to develop and use a model that incorporates other cost driving factors in order to develop estimates of sufficient quality at the preliminary design level.by Aristides Miroyannis.S.M.in Ocean Systems Managemen

The Airfloat HL project

A design study is described for a large low-cost rigid airship intended primarily for the movement of large indivisible loads (cargo) between industrial sites. A survey of the ship and its overall performance is followed by accounts of the operational procedures for the above function and for an alternative application to unit module transfer between fixed terminals. A final section indicates the estimated costs of construction and operation. Safety factors are also considered. Lifting devices such as winches, hoists are shown and described, and airship configurations are also shown

METHODOLOGY FOR THE SHIP EXPLOITATION FEEDBACK INCLUSION FOR IMPROVING THE SHIP DESIGN AND PRODUCTION PROCESS BASED ON ADJUSTED QFD METHOD

The relevant regulations of classification societies, national governments, IMO resolutions are included in the ship design and production process. However, it was noted that the shipyard does not include seaman’s experiential perception to a higher level, coming from specific requests and observations during the operation and maintenance of the ship. Such requests are based on good marine practice, for which the shipyards do not have a sufficient level of experience and feedback which leads to additional works and alterations to customer requests and expectations. Therefore, the authors in this paper propose a methodology for the implementation of the feedback from the exploitation of the ship with the purpose of improving the ship design and production process to reduce costs and to improve ship efficiency in exploitation. In the first part of the proposed methodology, the collection and analysis of feedback is made using the expert approach and the relevant documentation in order to identify the most common groups of remarks. Such analysis was used as an input within the adjusted QFD method for identification and ranking of those ship design and production processes that affect mostly on such remarks. Furthermore, the matrix of quality control is proposed within relevant sub-processes, and the guidelines for the remarks solving within ship design and construction process are defined. In this paper, the authors have primarily analysed outfitting and equipment related issues which are often emphasised as more critical to a ship hull structure production, though, structure issues are set for further research. Finally, a typical example of such guidelines implementation for improving the ship design and construction process is given

Ship production processes air emissions analysis

Compliance with modern environmental norms and regulations is an increasingly important requirement in the shipbuilding process of ship design and construction. Related to the ship production process, volatile organic compounds (VOCs), nitric oxides and particulate matter are the main emissions of harmful gases in the shipyard. This paper analyzes air emissions from the ship production process in a shipyard. Air emissions are quantified from either in-situ measurements from emission sources, or by materials that are used in the shipbuilding process, and the acquired data from those measurements is calculated as yearly emissions. Emission quantities of VOCs, nitric oxides, carbon dioxide, carbon monoxide and particulates are analyzed regarding possible reduction techniques considering efficiency and investment costs for using these methods. In conclusion, the best available and feasible emission reduction methods are suggested, and a suggestion for achieving the goal of a net zero emission shipyard

Application of queuing methodology to analyze congestion : a case study of the Manila International Container Terminal, Philippines

The objective of this paper is to apply queuing methodology in order to analyze congestion at the Manila International Container Terminal (MICT) in the Port of Manila, the Philippines. The vessels calling at the MICT have to wait in a queue before receiving services at berths because of congestion. For vessel operators and cargo owners this situation creates waiting time costs and delays in delivery of goods to final customers. One option to decrease waiting time is to expand capacity by increasing the number of berths. Construction of a new berth is a time consuming and costly procedure, which needs to be considered carefully before being implemented. To determine whether the data collected is suitable for queuing methodology, the distribution pattern of ship arrivals has been analyzed. The results reveal that the pattern of ship arrivals follows Poisson’s law of random distribution, which confirms the validity of the proposed queuing methodology. Applying queuing methodology, with the objective of minimizing total cost, including waiting time cost and berth’s construction costs, reveals that the number of berths at MICT is currently adequate. In order to release congestion, port managers must take other actions. Keywords: port capacity, port economy, congestion, queuing theory, container terminalApplication of queuing methodology to analyze congestion : a case study of the Manila International Container Terminal, PhilippinesacceptedVersio

HULL’S MANUFACTURING COST STRUCTURE

This study analyses the structure of costs of several processes associated with the shipbuilding industry. The analysed productive processes are: cutting preparation procedures, steel plate cutting processes, processes of hull plates and stiffeners forming, associated transportation and assembling of plates and profiles, and finally the welding processes. The methodology allows a shipyard to identify the main costs related to the manufacturing of the hull and the aspects that should be improved for increase productivity. The methodology adopted may easily be adapted by each shipyard creating a work database in order to improve and update these formulas by adding new corrective coefficients based on the type of the built ship or construction complexity of certain ship blocks. It is analysed 2 independent case studies that took place at different Portuguese shipyards and covering different aspects of the steel hull shipbuilding processes. The first case study considers time and cost analysis of cutting preparation processes made by the design office, cutting/marking of steel plates and forming processes of stiffeners and hull plates, required for the construction of an 83m Hopper Barge, built by MPG, at LISNAVE Mitrena Shipyard, Portugal, 2010. The second case considers the time and cost analysis of stiffeners cutting, steel plates and stiffeners assembly and welding, associated with the building of several blocks of an 80m fisheries supporting vessel by JOPERINOX Shipyard at Alverca, Portugal, 2008

Optimización del esquema de bodegas utilizadas para el almacenamiento de materiales de construcción y reparación naval

The paper shows the evaluation of applying models to improve efficiency in management of warehousesused in shipyards, focused on pick up, packing, and shipping activities, supported among others on theproposal by Rosenblatt and Roll (1984) to optimize the layout for storage and handling of materials neededfor ship construction and repair. Besides proposing the best physical layout for the storage of goods, themodel seeks to minimize three types of costs: costs related to the initial investment (construction andmaintenance), shortage costs, and costs associated with storage policies. The optimal design is foundthrough analytical optimization and simulation techniques.El articulo muestra la evaluación de la aplicación de modelos para mejorar la eficiencia en el manejo de bodegas utilizadas en astilleros, centrada en actividades derecolección, embalaje y envío, soportada entre otras en la propuesta de Rosenblatt y Roll (1984) para la optimización del diseño para el almacenamiento y manejo de los materiales necesarios para la construcción y reparación de buques. Además de proponerla mejor distribución física para el almacenamiento de las mercancías, el modelo busca minimizar tres tipos de costos: costos asociados a la inversión inicial (construcción y de mantenimiento), un costo de escasez y los costos asociados con las políticas de almacenamiento. El diseño óptimo se desarrolla con una combinación de optimización analítica y técnicas de simulación

Benefit-Cost Assessment of the Port Mackenzie Rail Extension

Costs We assume that the Port MacKenzie rail extension would cost $275 million to construct.1 This is a conservative estimate based on a range of between$200 million and 300 million for different route options. The time horizon runs 50 years from 2012 to 2061. O&M costs are assumed to be 1.5 million per year, with a net present value of $26.1 million. The net present value of all costs using a 5$301.1 million. Benefits The rail extension would provide two distinct types of benefits: 1) It reduces the cost of rail transportation; and 2) It is likely to stimulate significant new mines and other major development. These benefits come from a diverse mix of potential projects – thus a strength of the rail extension is that its economic viability does not depend on any one project. Reduced transportation costs Relative to Seward, using the extension would save 140.7 miles per one-way trip.3 Assuming an average cost savings of 6 cents per ton-mile and a 5.0% real discount rate, we estimate that using the extension would save $572 million in avoided rail costs, avoided port costs, and avoided railroad and road upgrades. These savings are shown in the table and figure on the following page. In addition to the above, we estimate that about 22,000 train crossings of Pittman Road and other roads would be avoided by the extension, saving motorists up to 64,000 vehicle-hours of travel time delay between now and 2061.Matanuska- Susitna BoroughExecutive Summary / Introduction / Benefits from Reduced Transportation Costs / Fiscal benefits to State of Alaska / Community and Regional Economic Impacts / Reference