Development of the ship hull assembly sub-process

Objective: The development of the ship hull assembly process is possible by changing the method of assembly of basic parts at the building site, which would shorten the duration of the process and lead to cost reduction. One of the possibilities is to increase the dimensions and mass of basic building units, as well as the crane capacity at the building site. Methods: Ship hull assembly methods involving sections, blocks and modules are used in the hull assembly phase. In the world’s best shipyards, ships are built from blocks or modules, in which as much equipment as possible is installed. This paper uses the finite element method (FEM) for structural analysis, and its results serve to define the optimal technological instructions for the vertical transport of ship hull structure blocks. Results: The development of the ship hull assembly sub-process can be achieved by using the hull block assembly method instead of the hull section assembly method. For the ship presented in this paper, the mass of a block transported to the building site was increased 3 times, so the number of building units was reduced by 65%. This reduces transport activities on the building site and shortens the duration of the assembly process by 20%. This paper shows that strengthening the block structure with temporary stiffeners is necessary for safe transport. It is possible to optimize their number and layout by using structural analysis. Conclusion: The development of numerical finite element methods, software packages, and computers allow wider use of structural analysis in solving engineering problems in shipbuilding technology. The simulation of realistic situations, a wide range of analyses and a large number of results become possible, and they raise the level of knowledge and enable better decision-making in the production process

Development of the ship hull assembly sub-process

U ovom diplomskom radu na primjeru jednog karakterističnog bloka trupa iz proizvodnog programa Brodosplita, analizirane su deformacije i naprezanja strukture prilikom vertikalnog transporta te optimizirana privremena pojačanja i ukrepljenja konstrukcije trupa. Analizirane su i prikazane mogućnosti unapređenja podprocesa montaže trupa uz korištenje dizalica većih kapaciteta s ciljem smanjenja trajanja montaže trupa broda na građevnom mjestu, opisanom detaljnije u uvodnom dijelu radu. Diplomski rad sastoji se od 7 poglavlja uključujući prvi uvodni. U prvom poglavlju, razmatrana je važnost preklapanja procesa gradnje broda u okvirima agilnog planiranja različitih aktivnosti unutar različitih procesa i podprocesa gradnje broda, te ukrupnjavanje sekcija trupa broda u blokove trupa radi ubrzanja odnosno poboljšanja podprocesa gradnje trupa broda na građevnom mjestu. Već na kraju prvog poglavlja se dotičemo tehničkih značajki dizalice kao i uloge vertikalnog transporta. U drugom poglavlju prikazan je opći pregled dizalica kao jedan od ključnih čimbenika u procesu gradnje broda. Opisane su karakteristike građevnih mjesta, uz osvrt na tehničke karakteristike i značajke dizalice, kao i na njihovu učinkovitost pri aktivnostima vezanim za vertikalni transport blokova sa primjerima domaćih brodogradilišta. Zatim će se napraviti osvrt. Podjela trupa broda na grupe i sekcije, te osnove karakterističnog bloka sa svojom strukturom i geometrijskim značajkama su predstavljeni u trećem poglavlju. Kroz četvrto poglavlje opisan je detaljnije karakteristični blok nadgrađa, od kojih sekcija se sastoji i kako se okrupnjuje. Također je prikazana faza predmontaže karakterističnog bloka i materijali koji se koriste za privremene ukrepe. Četvrto poglavlje je zaokruženo pregledom i analizom vremena potrebnog za montažu i demontažu ukrepa. Peto poglavlje se bavi modeliranjem bloka konačnim elementima i strukturnom analizom bloka nadgrađa. Zbog javljanja problema pri transportu blokova, jer neadekvatan transport može uzrokovati značajne deformacije za čije otklanjanje treba veća količina radnih sati, peto poglavlje se dalje bavi prikazom podizanja blokova i mogućih primjera deformacija struktura. U šestom poglavlju je ponuđena usporedba vremena i troškova potrebnih za montažu trupa broda prilikom gradnje sa blokovima i sekcijama. Zaključno su dani rezultati modeliranja i analize, važnost primjene strukturne analize, mogući problemi koji se javljaju i preporuke.In this master thesis, based on the example of a typical hull block offered by shipyard production portfolio, the deformations of the structure during vertical transport will be analysed and the temporary reinforcements and stiffening of the hull structure will be optimised. The aim of this work is to analyse and present the possibilities of optimising sub-processes of the ship's hull assembly with the use of larger capacity cranes to reduce the scope of equipping superstructures after launch, for instance on the equipment shore, with significant cost and time savings, described in more detail in the introductory part. The thesis consists of seven chapters including the first introductory one. In the first chapter, the accent will be set on the importance of overlapping of the shipbuilding phases related to the agile planning of various activities within different shipbuilding processes and sub-processes. Furthermore, the first chapter focuses on enlarging hull sections into hull blocks to accelerate or improve the hull construction sub-processes on the slipway. The second chapter describes the characteristics of construction sites, with reference to the technical characteristics and features of the crane, as well as their effectiveness in activities related to the vertical transport of blocks with examples of some domestic shipyards. The second chapter carries on with presenting a general overview of cranes as one of the key factors in the shipbuilding process. The division of the hull into groups and sections, and the basics of the characteristic block with its structure and geometric features are presented in the third chapter. The fourth chapter highlights in more details the characteristic block of the hull, its sections and how it is enlarged. The pre-assembly phase of the characteristic block and the materials used for the temporary supports are also explained. The fourth chapter is rounded off with an overview and analysis of the time required for the assembly and disassembly of the measure. Chapter five analyses a block modelling with the finite elements and portrays structural analysis of superstructure blocks. Due to the problems in the transport of blocks, given the fact that an inadequate transport can cause significant deformations, which require a larger number of working hours to eliminate, the fifth chapter further elaborates on the blocks’ lifting and possible examples of deformations of structures. The sixth chapter offers a comparison of the time required to assemble the hull during construction with blocks and sections. The results of modelling and analysis, the importance of applying the structural analysis, possible problems that may arise, as well as the recommendations are highlighted in the last chapter

Development of the ship hull assembly sub-process

U ovom diplomskom radu na primjeru jednog karakterističnog bloka trupa iz proizvodnog programa Brodosplita, analizirane su deformacije i naprezanja strukture prilikom vertikalnog transporta te optimizirana privremena pojačanja i ukrepljenja konstrukcije trupa. Analizirane su i prikazane mogućnosti unapređenja podprocesa montaže trupa uz korištenje dizalica većih kapaciteta s ciljem smanjenja trajanja montaže trupa broda na građevnom mjestu, opisanom detaljnije u uvodnom dijelu radu. Diplomski rad sastoji se od 7 poglavlja uključujući prvi uvodni. U prvom poglavlju, razmatrana je važnost preklapanja procesa gradnje broda u okvirima agilnog planiranja različitih aktivnosti unutar različitih procesa i podprocesa gradnje broda, te ukrupnjavanje sekcija trupa broda u blokove trupa radi ubrzanja odnosno poboljšanja podprocesa gradnje trupa broda na građevnom mjestu. Već na kraju prvog poglavlja se dotičemo tehničkih značajki dizalice kao i uloge vertikalnog transporta. U drugom poglavlju prikazan je opći pregled dizalica kao jedan od ključnih čimbenika u procesu gradnje broda. Opisane su karakteristike građevnih mjesta, uz osvrt na tehničke karakteristike i značajke dizalice, kao i na njihovu učinkovitost pri aktivnostima vezanim za vertikalni transport blokova sa primjerima domaćih brodogradilišta. Zatim će se napraviti osvrt. Podjela trupa broda na grupe i sekcije, te osnove karakterističnog bloka sa svojom strukturom i geometrijskim značajkama su predstavljeni u trećem poglavlju. Kroz četvrto poglavlje opisan je detaljnije karakteristični blok nadgrađa, od kojih sekcija se sastoji i kako se okrupnjuje. Također je prikazana faza predmontaže karakterističnog bloka i materijali koji se koriste za privremene ukrepe. Četvrto poglavlje je zaokruženo pregledom i analizom vremena potrebnog za montažu i demontažu ukrepa. Peto poglavlje se bavi modeliranjem bloka konačnim elementima i strukturnom analizom bloka nadgrađa. Zbog javljanja problema pri transportu blokova, jer neadekvatan transport može uzrokovati značajne deformacije za čije otklanjanje treba veća količina radnih sati, peto poglavlje se dalje bavi prikazom podizanja blokova i mogućih primjera deformacija struktura. U šestom poglavlju je ponuđena usporedba vremena i troškova potrebnih za montažu trupa broda prilikom gradnje sa blokovima i sekcijama. Zaključno su dani rezultati modeliranja i analize, važnost primjene strukturne analize, mogući problemi koji se javljaju i preporuke.In this master thesis, based on the example of a typical hull block offered by shipyard production portfolio, the deformations of the structure during vertical transport will be analysed and the temporary reinforcements and stiffening of the hull structure will be optimised. The aim of this work is to analyse and present the possibilities of optimising sub-processes of the ship's hull assembly with the use of larger capacity cranes to reduce the scope of equipping superstructures after launch, for instance on the equipment shore, with significant cost and time savings, described in more detail in the introductory part. The thesis consists of seven chapters including the first introductory one. In the first chapter, the accent will be set on the importance of overlapping of the shipbuilding phases related to the agile planning of various activities within different shipbuilding processes and sub-processes. Furthermore, the first chapter focuses on enlarging hull sections into hull blocks to accelerate or improve the hull construction sub-processes on the slipway. The second chapter describes the characteristics of construction sites, with reference to the technical characteristics and features of the crane, as well as their effectiveness in activities related to the vertical transport of blocks with examples of some domestic shipyards. The second chapter carries on with presenting a general overview of cranes as one of the key factors in the shipbuilding process. The division of the hull into groups and sections, and the basics of the characteristic block with its structure and geometric features are presented in the third chapter. The fourth chapter highlights in more details the characteristic block of the hull, its sections and how it is enlarged. The pre-assembly phase of the characteristic block and the materials used for the temporary supports are also explained. The fourth chapter is rounded off with an overview and analysis of the time required for the assembly and disassembly of the measure. Chapter five analyses a block modelling with the finite elements and portrays structural analysis of superstructure blocks. Due to the problems in the transport of blocks, given the fact that an inadequate transport can cause significant deformations, which require a larger number of working hours to eliminate, the fifth chapter further elaborates on the blocks’ lifting and possible examples of deformations of structures. The sixth chapter offers a comparison of the time required to assemble the hull during construction with blocks and sections. The results of modelling and analysis, the importance of applying the structural analysis, possible problems that may arise, as well as the recommendations are highlighted in the last chapter