The meaning of information in assuring the quality of constructional, technical, organisational and manufacturing processes of shipbuilding

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1 The meaning of information in assuring the quality of constructional, technical, organisational and manufacturing processes of shipbuilding A. Wolnowska, ^ E. Niesyty, ^ ^ Technical University of Szczecin, Al. Piastow 41, Szczecin, Poland wolanna@wsm.szczecin.pl ^ Technical University ofpoznan, Strzelecka 11, Poznan, Poland niesyty@iiz. me.put.poznan.pl Abstract The paper emphasises the importance of choosing proper methods of collecting and processing information as the basis for quality company management. Its aim is to achieve the best quality of products. The basis for discussion are shipbuilding processes. 1. Introduction The shipbuilding is accompanied by a complicated process of collecting and treating information of very different nature and destination. Some information is of economical and marketing character, it comes into the backlog orders, in which the significant role play the constructional guiding principles that operate the design process. Some information operates the technological processes of shipbuilding. In order to understand the importance of information in shipbuilding we have to analyse thoroughly the stages and processes it consists of.

2 694 Marine Technology 2. The ship design On the projecting stage the most important is information that allows to begin the planning. It makes the constructional guiding principles. The shipowner and design office take part in preparing the basic information. On the basis of this information the initial project is created. Its Tightness, quality and accuracy depends on the completeness and quality of information, that was used to form the assumption or the constructional guiding principles The initial project The initial project usually consists of the following : a) the general arrangement and the technical description, b) the power station plan with the list and description of important equipment and auxiliary mechanisms, c) the cross sections of the hull, d) the conceptional design of equipment, cabin furnishing, decorations etc., e) the table of approximate capacities of holds and tanks, f) list of passengers and crew, g) the technological design, e.g. Doerffer*. At this stage some deviations from the final project may appear which are caused by the incomplete or unprecise data. At this stage it may appear that each of those deviations causes great difficulties in designing process and it can even lead to redesigning. The most important is information regarding the main ship elements such as the main dimensions, capacity, speed etc. Approval of the initial design enables proceeding to the next stage The technical and manufacturing project The next stage in shipbuilding is the technical project. It consists of: a) the classification drawings. They need to be in accordance with the requirements of classification societies which will supervise the ship construction. b) the constructional drawings and calculations. They refer to all equipment, installations, furnishing etc. c) the list of materials witch technical specifications. The technical project is accepted by the shipowner who can require the supplementary changes. This acceptance is very important. It allows to send the drawings to the shipyard and order the materials. It is the proof that the requirements are agreed both by the supplier and customer. It allows to avoid misunderstanding in the next stages of shipbuilding and it protects against unnecessary costs. That is why it must be agreed which corrections will be

3 Marine Technology 695 covered by the shipowner and which by the shipyard. It is very important because every single correction is expensive and troublesome. The working project consists of all drawings that serve as a constructional documentation to execute work on the workshop. It requires a great precision. This is the end of the real ship designing The designing of ship technology The next stage of shipbuilding is the creation of technological project. It starts with the initial phase which includes information about the place and method of construction. It mentions necessary resources. According to them the hull is divided into sections. Then the technological process on the site is planned, then the guiding principles for preparing equipment in accordance with the chosen method of building, are defined. The technological project should contain the following: a) assembly schedule and welding sketch, defining of the admissible lacks and the ship positioning on the slipway according to demands of the classification society, b) the range and methods of the hull outfitting. Furthermore, the technical project should consists of the model schedule of the hull building and outfitting with division into technology items, stages and the building regions, the analysis of labour and material costs and analysis of the possibilities of shortening cycle at serial production. It is also necessary to make the documentation of the additional production equipment in accordance with the chosen method, e.g. Doerffer*. At this stage the ship designing and designing of her manufacturing is completed. It is followed by detailed constructional, technological and economical documentation. From the quality of information that is enclosed in this documentation depends the course of the building process and ship exploitation. That is why the initial designing is so important. Mistakes that are made and not removed at this shipbuilding stage can be difficult to dispose later on and what is the most important the cost of correcting them grows rapidly. The aim of this stage of the shipbuilding is to project the ship that would have the highest possible quality achieved with the lowest expenses and the smallest material consumption. 3. The manufacturing process of the shipbuilding 3.1. The manufacturing process The main goal of production is to make the product of the highest quality. This process comprises the technological and nontechnological processes. First of them are the processes that change the shape, the external appearance and

4 696 Marine Technology internal features of the work subject for example: the structure, hardness etc. They also join particular elements in sub-sections and in the final product. Second of them do not influence directly on the work product but they condition and speed up the first processes. To the nontechnological processes we include measurements and control, transportation, servicing of work stands, the machines and equipment repair, and many others Kinds of production and the technological process The characteristic feature of the production process is the repeating the same operations at the particular work stands. According tp the above production can be divided into: a) the mass production where one performs only one and the same operation, b) the serial production where at the particular working stand different working operations are performed, c) the individual production where at the particular stand different working operations are realised. In the shipbuilding industry the mass production can exist only for very small units. The serial and individual production is more frequent. In the case of big ships a lot of recurrent elements from which the ship is constructed can be mass or series produced. The individual production is much more difficult than the serial production because the particular operations are not repeated at all or are repeated very rarely. For their realisation workers with high and extensive qualifications and experiments, who can perform various operations, need to be employed. The standardisation of those kind of operations is more difficult because they appear, seldom they are not repeated and not included into the norms that are technically explained. The significant impact on the performance of those kind of operations and on the product quality have the worker's independence, competence and attitude the gear quality and technological elaboration of the particular processes have a great influence on the course and results of all serial production. That is why before starting the production the prototype and prototype series are deliberately built. After making corrections and constructive changes the building of the prototype series starts to asses the Tightness of the chosen technological process and gear. This series is prior to the proper series production what gives enough time to make corrections in the documentation. The recurrence of the operations makes it easier to form the efficiency and the quality of the process. In those kinds of processes the mechanism of the information feedback can be used. It allows to improve the process day by day. Because each product, including the ship, is produced in more or lesso complicated process man influences its quality, in other words he influences features and parameters obliquely inducing the cause of the production process.

5 Marine Technology 697 Man also influences the run of the process with the help of his own body using particular instruments, machines and equipment. Knowledge used by man to direct his activities is the medium which helps to manage both his work and indirectly the production process. In firms as complicated as a shipyard knowledge needed to manage the shipbuilding processes is found in minds of many specialised workers: designers, managers, auxiliary workers and executive workers. In consequence of this the management of the executive on the work positions is indirectly realised by the controlling and supportive staff and designers. The quality management depends on the possessed knowledge quality that is used by the particular workers. The important component of this knowledge is information. The second condition of the effective management is the integrity and cohesion of used knowledge and its adequacy to the content management processes. The creation of product project and the creation of the technology product belong to the management of the shipbuilding process, but in practice it precedes the building process. Because both the ship project and her building technology project come into being before the building process, the process of building in this stage is administered from one side by executive workers, from the other side by auxiliary and controlling staff who using the project documentation and gained experience controls and corrects the course of the particular processes so that they can finally reach the projected quality that is to say the projected features and parameters. It can be said here that management quality in the shipbuilding is assured by the creation of the proper administration system where the key role plays the information system, in other words system of generating, transferring and transformations of information. The condition to achieve to high work efficiency and proper product quality is careful constructional elaboration and technological shipyard preparation. It requires to create the information connections between all functional firm elements that is to say the information system whose objects of tooling is for example utilisation of labour, basic and auxiliary materials, machines and devices. The significant role in this system plays the preparation of the technological production, which consists of: a) the analysis of producibility of construction and elaboration of the optimum technological process, b) projecting and realisation of gear and particular devices for the shipbuilding according with adopted devices for the shipbuilding according with adopted variant of technological process, c) the division of construction and work on technological teams and calculation of their labour consumption, d) elaboration of the lists of completed materials for each technological team, e) elaboration of the model and productive schedules for the ship and all series witch comparison intentional production to the productive shipyard and particular workshops at the same time.

6 698 Marine Technology The range of those elaborations may be different. However, they should be limited to those which are indispensable. The technological documentation ought not to exceed the essential range in order not to create unneeded information noise. The most important thing in the shipbuilding management is organising, superintendence and maintaining in the proper efficiencies the information system that operates the shipbuilding process. It is the shipyard management obligation. From the quality and cohesion of this system, the efficiency of the shipyard as a firm is dependant. The main problem is to create the information system that would allow to manage efficiently of the shipbuilding process. The most important point of the system is to link of the customer requirements with the shipyard possibilities and to transform the adjusted standard with the shipbuilding process. 4. The Taguchi's method in the process management According to Taguchi "projecting, which is aimed to lessen the unproper product impact, lessen the probability of defects occurrence in the production process at the same time",e.g. Lambert*. The Taguchi logic is following. The " zero of defects " idea focuses the management attention on the variability in production processes which cannot exceed the accepted deviations from the given values, for example deviation of the thickness within the bounds of ± 0,091 mm. Taguchi proves that every deviation from the founded values causes loss. It is the result of inaccuracies of information which causes for example making the wrong decision on the work position. The weakness of the "zero of defects" is the fact that in every product series a considerable number of elements has the parameters that are close to the external values of the admissible tolerance. What is more, many other components which are put into one complicated product have similar features. After adding up they can lead to the drastic lowering of the general parameters what may result in the poor final quality. The consequences of not controlled variability of elements, badly read or delivered information in the productive process of the complicated device can have catastrophic results. The plane produced in accordance with the accepted tolerance units for each part can consist of many elements which fitted into the allowed limits but in sum may cause the defectiveness of the plane. The situation is described under the name of cumulation the tolerated deviations (stack-up). Stack-up takes place when not dangerous individual element changes in undesirable direction the characteristic of work of different element etc. The catastrophic results can appear when the general deprivation being an account of accumulated deprivation in many parts and elements are at the extreme of the accepted tolerable limits reaches the critical point. Then the all machine can break up in pieces.

7 Marine Technology 699 The presented example clearly shows that the proper information system should be organised in the way that would exclude the appearing of undesirable results. This example reveals how in a seemingly rational organised and hermetic system of information circulation not administered areas appear. 5. The model role in the information management The described example showed that information used to manage the production processes requires split-levels interpretation. It means that we cannot include to the one qualitative category all elements that have parameters fitting into accepted limits. They ought to be differentiated on subclasses that would allow to unit in the complicated product those elements which have defections that obliterated with each other that means that it is necessary to create models of processes that would take into account described occurrences. Only then information about possessing particular features by an element gather proper meaning. In described defections chance it allows to make proper technological interpretation of the information meaning of parameters. It requires to operate the model conception which explains the course and interdependence structure between the elements of the investigated (administered) system, for example technical. Such model is valuable (it usually has the figure of metaphor, in other words the hypothetical picture that describes the nature and structure of the analysed occurrences or processes) because it allows to define the characteristic and way of generation of information chasing the control points and constant interpretation of particular isolated data. The model is more effective when it better explains the nature, structure and course of the model productive process. The management of the firm which is not only the productive system requires using many different models, for example: economical, social, technical etc. Those models serve a lot of functions. They create a unit language and the communication way in the firm, what helps to co-ordinate activities in the firm. The simplest example of such models are procedures. In order to use models in a proper way procedures should: a) possibly concise reflect what is happening in the firm, b) do not cramp the inventiveness of workers, c) to standardise the processes understanding, d) to standardise the culture of organisation, e) to standardise the language, f) to hand down knowledge from generation to generation. The firm existing on a changing market is forced to make systematically new products, elaborate new technologies and to change its way of economic working. That means that it has to generate new models that allow to compete with others. At the same time its information system has to not only be able to

8 700 Marine Technology improve known and used practises but also produce new. That is why from some time it is said that the most effective are the organisations that learn by themselves. The ability to develop used information models (knowledge) and particulary the ability to generate new ones is nowadays the key to the development of economic organisation and improvement of firm management systems. The ability to improve the processes in the firm allows to achieve a success. The measure that enables this improvement is focusing attention on building elastic and efficient system of information in the firm. 6. Conclusion The more complicated the firm is, the more complicated information system it requires as the basis for managing. as an axis of its managing it needs. The norms of ISO series 9000 consist of a model of such a system. It is called the quality system. Nowadays, big companies create more integrated and complicated management systems on all the levels of the firm work. Those are the systems of total management quality. Our aim was to focus on the particular importance of knowledge and information in the management of shipbuilding processes. We also wanted to emphasise the fact that the success of the firm as complicated as a shipyard depends on their ability to create the efficient, information system which is able to generate new knowledge that is ahead of the requirement of the market. References 1. Doerffer, J., The technology of ship hull building, The Marine Publishing House, Gdynia, pp , Flood, R.L, Beyond TQM, Wiley, England, pp , Lambert, T., The management problems, ABC Publishing House, Warsaw, pp.40-41, Nonaka, I., Takeuchi, H., The Knowledge-Creating, Oxford University Press, New York, Storh, R.L., Hammon, C.P., Moore, R.C., Ship production, Cornel Maritime Press, Maryland, 1995.