Modularization of Ships

Modularization of Ships Report within the Framework of Project “Intermodul” s/03/G IntermareC

Volker Bertram ENSIETA 2 rue François Verny F 29806 Brest Cd 9 France [email protected]   [email protected]

7/28/2005

1. Introduction

In today’s international competitive shipbuilding market, success is often based on offering both competitive prices and competitive delivery dates. Over the last three decades, there has been a continuous pressure to improve shipbuilding performance, to reduce build times and to reduce costs. The initial focus of cost reduction efforts was on steel processes and there is still progress to be made on design for production of steel structures, e.g.  Lamb (2003). However, as the scope for further improvement in the ship structure production and assembly techniques diminishes, the shipbuilding industry explores increasingly also other options to save time and money, namely equipment and outfit (E&O) as typically second largest cost item in a cargo ship. E&O offers the possibility of significant improvement,  Bruce and Nielsen (2003).  While advanced outfitting (outfitting sections before assembly) is problematic for some shipyards and ship types,  Bruce and Nielsen (2003), Lamb (2004), modularization and standardization are widely seen as areas where considerable progress is still  possible. Before looking into specific applications for ships, we recall the definition of modularity credited to  Booz-Allen (1968), as quoted by Spero et al. (1971): Constructed of modules or unit packaging schemes, usually having all major dimensions in accordance with a prescribed series of dimensions; capable of being easily joined to or detached, as an entity, from other components, units, or next higher assemblies. The general approach is tried and proven in assorted industries like aerospace, automotive, or appliances. E.g.  Rommel et al. (1995) report findings of McKinsey & Co.: ‘Winners’ shift the freeze  point (i.e. the point where the product variety is created in production) as late as possible in the  production. Standard parts and modular approaches offer gains in time, cost, and quality. The principle is generally understood. ‘Winners’ and ‘Losers’ in the McKinsey study differed in how consequently they implemented the modular approach.

Common platform, but product variance – One success story for modular design 2. General guidelines

The modules can be built and tested in parallel at the providers’ premises. This shortens the overall construction time, reduces the risk for integration of the various systems, and therefore means overall cost savings for the whole ship. The general objectives of the Modular Ship Design concept are: - reduced design and construction cost - reduced design and construction time - greater flexibility for updates later in the ship’s life (temporary for missions or general update) - shorter and cheaper maintenance periods 2

- reduced maintenance cost However, modularization comes at price: - higher initial design effort - reduced design freedom (possibly retarding technological progress) - usually higher weight - usually increased space requirement Creating ever larger standard modules and shifting outfitting to workshops (in ship yards or to subcontractor sites) is not without dispute and optimal advanced outfitting levels depend on ship type and ship yard,  Lamb (2004).  However, modularity and standardization at unit level are commonly  practiced at world class ship yards. One example are modular cabins/bathroom modules, Hoffmann and Lamb (2003) .  Ichinose (1978) describes very early implementation of standard components and modules at the Japanese shipbuilder IHI. Continued efforts at IHI have resulted in numerous related  patents1.  Boudreaux et al. (1986)  present modular concepts at Avondale shipyards in the USA, which followed from a cooperation with IHI. Paetow (1997) describes efforts of the German shipyard HDW within the framework of the Euroyards consortium. As only two main suppliers shared the market for slow two-stroke diesel main engines, joint discussions between suppliers, shipyards and class resulted in a harmonization of the interface engine-foundation, allowing to progress with the steel structure while shifting a final decision on choice of main engine to a later point in time. A similar harmonization for four-stroke engines was deemed impossible due to the multitude of potential suppliers. Modules for cooling water and separator stations are mentioned as standards for HDW.

Standard furniture elements are arranged in standard cabins, http://intro.masa-yards.fi/

Modular accommodation unit

3. Case studies 3.1. Navy applications

The general trend to fewer warships having to fulfill a greater variety of mission in their life time motivates modular ship design and operation. Naval procurement programmes around the globe take advantage of the modular design and operation philosophy. Modular deckhouse

See: Spero et al. (1971) In 1967, the J.J. Henry Company investigated the feasibility and advantages of modular construction of ships’ deckhouses for MARAD. The concepts apparently were never put to practice. 1

 US Patent US005259332A “Method of forming modules and method for arrangement thereof” (1993), European patent EP 0470714A1 “Forming and arranging functional modules” (1991), cover grouping of outfits or plant elements into modules. US patent US005347703A “Method pf coupling a module framework to a ship structure” (1994), European patent EP 0473357A1 “Module frames” (1991) cover self-supporting frameworks consisting of standard modules to which outfits are mounted.

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Exploded view of modular deckhouse Affordability Through Commonality (US Navy)

See:

 Bosworth and Hough (1993), Hane et al. (1995), Cecere et al. (1995), Christensen and Koenig (1995)

In 1992, the US Naval Sea Systems Command (NAVSEA) began an initiative titled “Affordability Through Commonality” (ATC). The object was to develop the necessary strategies, standards, designs, specifications, and procedures for cost reduction through equipment modularization, equipment standardization, and process simplification. The ATC program primarily focused at HM&E (Hull, Mechanical and Electrical) modularity. Modules consisting of standard components are then assembled and interconnected in a workshop, possibly even outside the shipyard. Ideally a module must be applicable across several ship types across the fleet to increase equipment standardization. Standardization proved to be increasingly difficult moving from unit modules to system and zone modules. Tested in practice: standard fire pump module, reverse osmosis desalination module, modular crew sanitary space. Christensen and Koenig (1995)  analyzed how shifting to standard outfit  package units would affect production of the LPD 17 amphibious dock ship.

Reverse osmosis desalinator module (ATC)

SMART workstation modules

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SMART System (US Navy)

See:

 Alexander and Olmstead (1997)

The Shipboard Modular Arrangement Reconfiguration Technology (SMART) is a methodology for installing equipment in shipboard spaces to provide flexibility and cost efficiency. The heart of this technology is a track rail system, similar to that used by the aircraft industry, which enables equipment to be bolted to the deck, bulkheads or overhead. The SMART system includes a foundation track system, modular connected power and lighting, and modular workstations. NSSN Attack submarine (US Navy /Navy and Electrical Boat company)

See:

Carey (1997)

In the early 1990’s, Navy and Electrical Boat (shipbuilding division of General Dynamics) started the development of a new generation US attack submarine NSSN. The NSSN needed to be much more affordable than previous Seawolf class submarines, but also the design and manufacturing process had to be sufficiently flexible in order to adapt to mission requirements that could not be fully anticipated at the time the construction began. Therefore, the Navy and Electrical Boat focused on integrated  product teams, concurrent engineering and modular design and construction concepts. The design  philosophy stresses a three-fold modularity: in construction, in technology, and in operation. Schelde Naval Shipbuilding: Sigma Offshore Patrol Vessels and Enforcer

See:

www.scheldeshipbuilding.com - Sigma , Enforcer Post (2003)

In the 'Sigma' (Ship Integrated Geometrical Modularity Approach) philosophy of Schelde Naval Shipbuilding, a set of geometrical parameters are defined which are applied throughout the entire  product family, thus providing a repetition of identical units, both in the dimensioning of ship spaces as well as in the lay-out of systems. Furthermore, the hull form itself is 'modular'. With a few fore and aft ships, all hulls within the product family range can be created. The approach is applied at Schelde  Naval Shipbuilding to a range of Offshore Patrol Vessels (OPVs).

Combat system

Auxiliary systems

Propulsion

Accommodation

Support spaces

Schelde Sigma Offshore Patrol Vessel

Schelde ENFORCER concept

Also Schelde’s ‘Enforcer’ family (landing platform docks, multi-role vessels) employs the modular design concept offering pre-designed customized options for dock, garage, flight deck and hangar area, accommodation, and propulsion systems. The basis design consists of 5 modules, with distinctly grouped functions, like a hangar module, which facilitates the hangar and all helicopter support functions. These modules can be used across the entire range of Enforcers. Differences in length are created by inserting sections parallel mid-body sections. 5

MEKO Design Concept, by Blohm & Voss GmbH

See:

www.blohmvoss.com  Jacobi (2003)

MEKO is probably the best-known example of modularity in shipbuilding. In the patented 2  MEKO concept, all components needed to run a specific system are accommodated in a single module and modules are connected to the power supply, HVAC, and the data network via standard interfaces. MEKO mainly focuses at SEWACO systems (sensor, weapons and communications). More than 50 MEKO frigates and corvettes were built by 2003.

green: mast modules; red: weapon modules; blue: electronic modules; yellow: machinery; purple: pallets

MEKO principle, Blohm&Voss

MEKO modules, Blohm&Voss

MOPCO Concept, Abeking & Rasmussen

See:

www.abeking.com  Jacobi (2003)

The Modular Platform Concept (MOPCO) of the German shipyard Abeking & Rasmussen (A & R) is  based on experience since the 1980s when a replacement programme of German mine-counter measure vessels started. The concept is based on strict modularization of all systems and equipments which are integrated in an improved design of the common platform. There are standard interface connections for the various mission containers and equipment like winches and cranes.

MOPCO concept of Abeking & Rasmussen 2

 European patent EP1512618A2 “Schiff mit modularer Struktur” (ship with modular structure) (2004).

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SWATH@A&R

See:

 N.N. (2005)

Within the framework of preliminary studies for the MJ2000 (Minenjagd 2000 = mine hunting 2000) concept of the German navy, a consortium involving the shipyards Abeking & Rasmussen and Lürssen Werft have developed a SWATH platform which supports shock-elastically supported modules. The complete superstructure with accommodation and bridge is one module. Another module was developed for launching/retrieving drones. While the MJ2000 proposal failed to attract funding, Abeking&Rasmussen continued to develop the modular SWATH concept under the registered name SWATH@A&R. The platform contains only the absolutely necessary equipment e.g. maneuvering devices, electrically driven propulsion, fuel and ballast tanks. The platform is structurally self-supporting and carries modules which do not contribute to global strength and are in themselves structurally self-supporting. Bridge and engine room are added as base module located up front. The central module hosts the operational central and accommodation units, kitchen, and further equipment for the operation such as electric transformers. The aft module may be exchanged for individual missions, containing weapons, launching-retrieval systems for AUVs or boats.

MJ 2000 concept (Seepferd) of A&R

Modular platform concept of A&R

Standard Flex (Flyfisken Class)

See:

www.navalteam.dk/flex300.htm, www.naval-technology.com/projects/fly  Rodholm (1990), Hornhaver (1995), Jacobi (2003)

The Standard Flex 300, also known as the “Flyvefisken Class”,  is a multi-role vessel based on a standard hull with containerized systems and equipment, which allows the vessel to change role quickly for surveillance, surface combat, anti-submarine warfare, countermeasures/mine hunting, or  pollution control tasks. This fiber-reinforced plastic vessel is designed by the Danish Navy and  Navalteam Denmark (project group of Danyard and the Nordic Defense industry). Between 1987 and 1996 a total of 14 of these vessels were built by Danyard A/S. The principle of the STANFLEX 300 concept were adapted for the three (much larger) fishery protection / offshore patrol vessels of the ‘Thetis’ class, and the flexible support ships of the Absalon class.

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Standard Flex module

Standard Flex System

French-Italian FREMM (frégate européenne multi-mission)

See :  Desclèves and Letot (2000), Desclèves (2004) The French navy in cooperation with the Italian navy develops new frigates. Within the next decade 17 new frigates shall be built for France, 10 for Italy. Following the success of the Danish Standard Flex approach, the frigate design shall be based on a modular ship design approach to provide the desired flexibility and cost effectiveness. The concept foresees a standard platform, fitted with equipment shared by all operational functions. This ‘plug&play’ concept shall make it easier to stay abreast of new systems developments. 3.2. Civilian applications M1000 System

See:

Gallin (1977)

In the 1960s, driven by a demand to replace the Liberty ships built during World War II, Blohm+Voss developed a “design for production” ship called ‘Pioneer’. The ship included a series of novelties, including a prefabricated accommodation system M1000. The M1000 system consisted of a steel framework for cabin structures, in standard parts, in meter measurements equipped with standard metric furniture. Well thought out connection details and fire proof panels ensured quick assembly. While the Pioneer concept as such flopped, the M1000 accommodation system, taken separately,  proved to be a success. TNSW modular engine room

See:

Sell (1996), Baade et al. (1998)

After DFP projects to reduce costs in steel construction, Thyssen Nordseewerke (TNSW) concentrated on DFP in the ship engine room. The engine room, accounting for 40% of the production hours and ship costs, offered considerable potential for cost savings. This consideration led to the introduction of standardization and modularization in engine room design. In 1991 the yard started with the building of a series of 1500 TEU containerships in which piping and pump groups were replaced by completely assembled and pre-outfitted functional modules (low-temperature cooling water module; hightemperature water module; sea-water cooling module; separator module; lubricating and fuel oil module; starting air and control air module). After the first series of containerships, the module series was extended with some additional modules. In total, thirteen containerships were built between 1991 and 1996 with this (patented) modular engine room. TNSW also patented3  a concept of modular 3 US

patent US005899161A “Ship with plane area elements which extend horizontally and are located in the hull of the ship” (1999)

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supports for engine rooms which consists of vertical supporting columns in the hull supporting one of more horizontal rectangular deck elements.

TNSW machinery space unit

NASSCO machinery unit

TNSW modular support system for engine rooms Modular deckhouse

See: Höpfner (1997) A consortium of shipbuilding suppliers in Rostock/Germany started in 1998 with the prototype of a modular deckhouse. The deckhouse consists of five modules: (1) (2) (3) (4) (5)

accommodation cells, floors, nautical bridge, funnel, and appendages.

Decks consist of mass-produced laser-welded sandwich panels.

Modular deckhouse 9

Engine Room Built Strategy developed by NASSCO

See:

 Jaquith et al. (1996)

During the contract design phase of the Strategic Sealift New Construction Program engine room at the National Steel and Shipbuilding Company (NASSCO), the yard's management recognized that  procurement would be technically challenging and highly competitive. To reduce the construction time required for designing and building such a complex engine room, and due to facility and crane lifting constraints, a modular approach was taken instead of the conventional block outfit approach. This resulted in the innovative Engine Room Built Strategy, developed and supported by a Concurrent Engineering team. This resulted in a two-layer engine room, with ten lower layer modules and three upper layer modules. Each module contains one or more completely outfitted and tested systems. During the design of the modules, extra attention was paid to improve the piping and cabling architecture. According to NASSCO, the project proved to be successful, although some refinements are considered for future programs. PU-707

See:

 Altic et al. (2003)

 NASSCO continued work on modular and standard outfit of (US Navy) ships. A pilot implementation  project focused on production processes associated with the machinery unit PU-707. The outfitting unit consists of a foundation made up of angles, beams, and deck plates that support distributive systems, tanks, and equipment for the starting, control, and ship service air systems, lube oil transfer system, stern tube lip tank and electrical group control center, load centers, and display panel. The unit was re-engineered for modular outfit using a family of interim products, optimizing for repeated assembly. During the course of the project, it became obvious that a clear definition of an interim  product hierarchy was needed to reach agreement as to the defining criteria for each of the levels of the product hierarchy. The creation of a series of previously established products or a product family album, which could be built with established production processes, would make the preproduction evolution much quicker and cost effective. NSRP/ASE Project 21

See:

Tomassoni et al. (2003)

The project was initiated to improve ship design at US shipyards and to assist them in achieving commercial competitiveness. The aim is to develop a template-based design process utilizing standard ranges of parametric interim products (  modules). The project focuses rather on generation of product data templates. More than 200 such templates shall be developed in the project. ≈

Ulstein Modular Design Strategy

The Ulstein A101 (offshore supply vessel), launched in late 2002 was built using the Ulstein Modular Design Strategy. The DFP strategy is based on standardized components employed in different combinations to preserve flexibility in design while reducing cost. Little information on details is available, but the Ulstein website gives the reasoning of the shipyard management: “Modular design is about reusing knowledge and solutions. In other words, producing and utilizing good solutions of a vessel, or a system on board a vessel. We can build the simplest and the most advanced vessels and ship systems from modules. Thus we can also outsource all or parts of our production and use our expertise and the network we have at our disposal to produce vessels and systems more cheaply.”

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Ulstein modular design strategy Modular concept for small dredgers

See:

 Bilen (1989)

In this concept for the modular design and construction of small dredgers for inland waters the overall dimensions of the modules are within the international standard container dimensions to facilitate the transport from supplier to customer. The modules are connected by specially constructed wedges which provide easy connection and disconnection of modules. Several modules were developed: displacement module; propulsive displacement module; connecting modules; wheelhouse module; hydrostatic navigator; several dredging modules.

Modular inland waterway dredger Modular bulk carriers

See:

Parashkevov et al. (1989)

In 1989 the shipbuilding department of the Varna Higher Institute of Machine & Electrical Engineering developed series of modular transport ships (bulk carriers, product tankers, multi-purpose vessels). The bulk carrier range is based on the assumption that the ship’s width is kept constant along the range. Together with the selection of the topology of the main transverse section and the frame space on the one hand, and the special approach of the development of the hull lines on the other hand, high levels of ship forms and structure unification were allowed along the range. For all bulk carriers in the investigated range, the required section modules can be achieved by only changing the plate thickness and the transverse stiffeners, without changing the rest of the construction. The high level of unification between the construction of the different vessels, allows for easy group and in-series  production of module parts, units, sections and blocks. To further utilize the possibilities of unification the series is designed such that the arrangement and the equipment of all deck structures is the same for all ships.

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Modular ship hull design IIT

See :

 Misra et al. (2002), Sha et al. (2004)

The Indian Institute of Technology in Kharagpur patented4  a family of modular ship hull forms, combining a choice of one aft body, two fore bodies and six mid-bodies to generate a total of twelve hull forms. There is no information on implementation in industry.

Sha + Misra : Modular containership

Modular fast catamaran IRIS

See:

 N.N. (1994)

http://www.iris-catamarans.com The French shipyard Iris Catamarans in La Rochelle has developed a modular fast catamaran ferry family. The concept consists of closed modules for the passenger space (one or two decks), a control module which groups all functions of propulsion, steering, safety and transmission together, and the two side hulls which are connected by three strong girders. The side hulls contain engines, auxiliary engines, waterjets and electric systems.

Modular Iris Catamaran 4

 World Intellectual Property Organization patent WO2004/029839A2 “A method for modularization of ship hull” (2004)

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Futura Carrier

See:

 Mühlhausen (2004), N.N. (2005a,b)

www.new-logistics.com The Futura Carrier system is a modular system proposed for inland waterways transport vessels. The ship is equipped with 4 propulsion units, two astern and two forward. Aft and forward propulsion modules can be combined with standard accommodation units and cargo modules (tanker, container, general cargo). A prototype of this ship was built in 2005 by the German shipyard CON-MAR.

Futura Carrier 4. Conclusion

Despite the potential disadvantages, modularization is increasingly used by successful shipyards and navies, indicating that there is still considerable potential for improvement in the industry in terms of using modular approaches in design and operation. The fragmentation of the suppliers’ market for many items in equipment and outfit, together with the weak position of the customers (ship yards or ship owners, with the possible exception of large navies) prevents rapid progress in this respect. In addition, typical university curricula do not train young engineers in design for production and modular design. Other channels of dissemination should therefore be employed, e.g. through  professional societies, publications in journals widely read in the industry, standard text books, etc. Acknowledgement

Claude Morvan, as usual, did a great job in tracking down references. Jan-Jaap Nieuwenhuis, PhD candidate at TU Delft, supplied valuable material and discussion.

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