1. to conventional construction, modular construction requires greater interaction

 

 

1.           
The issues faced by the Indian defence
shipyards along with methods to overcome the existing capacity constraints were
brought out in chapter II. The concept of modular design and construction
technology adopted by leading warship building nations in the world was
discussed in chapter III. The success of modular concept, to a large extent is
dependent on shipyard’s facilities and construction philosophy / methodology.
Successful global shipyards use high end IT solutions, concurrent engineering,
a robust design department, large shipyard infrastructure to process highly
pre-outfitted mega blocks, weather independent construction, and finally, complete
digital shipbuilding. Compared to conventional construction, modular
construction requires greater interaction among construction activities,
requiring planning of many of these activities to occur early in the project and
redefines relationships among activities that are usually independent in
conventional construction.

 

 

Challenges
in Implementation of Modular Concept

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2.           
Design
Process.     Deciding
the appropriate level of design process is a challenge, which must be addressed
at the beginning of design phase. Conventional shipbuilding uses the concept of
“outside-in” design, where the design of hull form is carried out first
and then all systems are forced to fit within the physical hull. This leads to
unstable designs and increased cost. To overcome this, “inside-out”
design is used in modular construction where the systems are designed first,
and then the hull is designed to enclose the cumulative system volume and area
as mapped through functional allocation.

 

3.           
The efficiency of modular construction is also
greatly influenced by definition of modules during the early stages of ship
design. The modules should be designed to the extent possible with similar
volume, weight and shape characteristics in order to distribute work evenly
during fabrication and assembly levels prior block assembly. Down hand welding
should be carried out inside modules / blocks to provide good working
conditions for welders and improve the efficiency of welding. As modular
construction requires far superior engineering application, quality assurance
and design standards, adequate precautions need to be taken to minimise
failures which could otherwise lead to time penalties.

 

4.           
Cable
Laying / Installation.          Due
to the modular design of compartments and dividing the ship into blocks and
mega blocks, numerous cable installation works cannot be progressed
simultaneously. Cabling between equipment and sub systems within the module or
block could be undertaken and balance cabling could be undertaken only after
joining of all modules. The typical cable installation process starts with
logical design, cable routing, cable lay and cable sequencing. Re-engineering
current cable layout practices by selection of smaller work packages would
result in savings in material ordering, warehousing of cable, associated
footprint reductions in outfitting areas, and more timely installation of
cables in modules and on-board the ship. Bus modularity concept can be used during
design stage for interfacing the various systems and subsystems within /
outside a module in a much easier way.

 

5.           
Modular Technology for Combat Systems. Carrying
out assembling, pre-outfitting, integrated testing of combat weapon systems,
sensors, command and display hardware off-hull could reduce timelines for final
installation and checkout delivery of the integrated warship from months and
years to weeks1.
The ship can have a basic computing backbone with rigid interfaces which can
meet the interface requirements of weapon and sensors. Further, off-hull test
and simulation facilities, if created can help exploit the concept to its full
potential. The LCS program by US Navy has adopted this2.

 

Figure 1.        SEAMOD Distributed Combat System

 

 

6.           
Large Infrastructure to Enhance Pre Outfitting. Modular construction
increases block sizes and reduce the number of blocks per ship. Bigger blocks
enhance the percentage of modular construction and pre outfitting per block and
should be supported by other critical requirements like large infrastructure
along with land area for setting up facilities, crane / lifting capacities and
transportation systems for handling bigger block sizes. The final module when
constructed may weigh hundreds of tons (between 60 % to 90 % complete) and are
to be moved to the final consolidation site where they are aligned and then
welded together to form the completed ship hull. As brought out above, the
infrastructure facilities like crane capacity, trailers, dock space, buildings
etc. are considered essential for successful implementation of modular
construction.

 

7.           
Digital Shipbuilding.          Modularization
would largely depend upon the extent of digitization that is incorporated from design
stage to construction stage. The concept design is validated through
theoretical calculations (FEA, CFD analysis etc.) through a model test with
some designer’s margin. 3D modelling should be used in design activities
related to plates, profiles, piping, equipment, outfitting structures, and would
resolve most of the interferences and sequencing issues. To make maximum use of
these techniques and technologies, all DPSUs and private shipyards should have
integral design bureaus which employ these technologies. Modular outfitting concept incorporating digital
shipbuilding techniques would help in improving efficiency and cost
performance.

 

8.           
Developing and Retaining a Skilled Workforce.        Highly
skilled people with the knowhow of advanced modular technology are essential to
design, build and integrate the modules that comprise a large weapons platform.
The technology uses sophisticated 3D CAD tools. Production also requires many
proficient skills, such as electricians, welders, and painters as mil standards
are required to be ensured. These skills are critical and take time ‘to build
and to sustain’. Further, the overseeing team also require adequate training to
ensure quality of workmanship by the shipyard workers. Therefore, shipyards
must provide adequate training to its workers and ensure that the trained
manpower is retained for long time.

 

9.           
Binding
Data from IN.        Towards achieving higher indigenisation
levels on-board warships, a vast majority of equipment, weapons and sensors are
procured from PSUs like BEL, ECIL, HAL etc. and other nominated vendors. The
contract with the shipyard would mandate procurement of equipment from these
agencies only, limiting the shipyard’s control over these firms. Experience in
the past has shown that these nominated vendors have defaulted in timely issue
of equipment drawings, binding data and other details which severely affect the
shipyard’s planning process. Any delay caused by these cannot be attributed to
the shipyard.  Therefore, it is important
to formulate a mechanism by which the timely forwarding of equipment and
associated documents is undertaken by nominated vendors and is part of
responsibility of IN. A contract
could be signed between IN and these
agencies to ensure timely delivery of equipment to shipyards. CAG report also
brings out that delays in delivery of ships by DPSUs are also due to delay in
receipt of binding data3.

 

10.        
Modernisation
of Indian Shipyards.      Indian
DPSUs like MDL and GRSE are in the process of modernising, wherein 300 T blocks
are manufactured independently along with their equipment, electrical wiring,
pipelines, etc and then fitted to neighbouring blocks precisely. This could
result in construction of future destroyers in 72 months and frigates in 60
months4. Reliance Naval and
Engineering Ltd shipyard (erstwhile Pipavav Shipyard5) uses modular construction
and undertakes construction of blocks and mega blocks. The shipyard has large
infrastructure and facilities. For the final integration of mega blocks, the shipyard
has one of largest dry docks in India with all necessary yard facilities. However,
the shipyard could not implement the modular design and construction
methodology to its full potential due to several other issues and the NOPV
project has been delayed far beyond contracted timelines.

 

 

Successful Projects Implemented
Worldwide

 

11.        

MEKO Frigate Family.       Blohm
& Voss shipyard in Germany6 undertook the
implementation of modularity in the late 1970s, which created the MEKO
(“Mehrzweck-Kombination” or “multi-purpose-combination”) warships for the
German and other foreign navies. MEKO embraces the flexible installation of
weapon, electronic and major ship service systems in the form of standardized
modules and standardized interfaces. Blohm & Voss has built 60 MEKO ships
for 11 world navies. They have reported reductions in both construction time
and cost over traditionally configured ships7. The complete payload of a
MEKO ship can be quickly installed, removed, exchanged or replaced. Blohm &
Voss claims that modularization reduced the time from contract award to
commissioning from about 72 to
48 months. The modular production techniques reduced the production schedule by
up to 25 % and production costs by up to 10 %. This yielded market advantages
and in 20 years, the yard sold more than 200 of their MEKO Frigates. The MEKO
facilitates parallel design and production of weapons, sensor, electronics and
outfit modules. For the design and construction of the MEKO 200PN, an elapsed
time of approximately 50 months from contract award to delivery was achieved
and for a F123 Destroyer, an elapsed time of 62 months was achieved. The ship
design process ensures a high level of outfit planning and integration with steelwork
production, and is further enhanced by the advantages offered by the MEKO
system of outfit modules.

Figure
2. MEKO Modular Concept

 

 

 

 

 

 

 

 

 

 

12.        
Comparison chart of a conventional Frigate with
a MEKO Frigate is shown in Figure 3.

Figure 3. Time frame
between a contract coming into force and commissioning

 

 

13.        
Air
Warfare Destroyer.      The
Hobart Class destroyers8 of Royal Australian Navy are
being built using modular construction method. Each ship is made of 31 blocks
which are being manufactured by three Australian and one Spanish shipyard. Much
of the internal fit-out of the blocks including installation of equipment
mountings, piping, electrical cable trays and hangers and trial fitting of
heating / cooling and ventilation would be completed before consolidation as it
is easier and safer to access tight spaces this way.  During consolidation, pre-launch outfitting and
supporting sub-systems such as piping and cabling were connected between
blocks. The first of the three ships, weighing approx. 5000 tonnes was
transported to the ship-lift and final outfitting undertaken. 70% of the
modules were built at a different facility than the erection facility9. The first ship of the
class was commissioned in Sep 201710 with a delay of almost
one year view other issues which affected the program.

Figure 4. Hobart Class Destroyers – Blocks
and their allocations to various shipyards

 

 

14.        
Modular
Approach Adopted by US.      The
US commenced the study of modularity in Navy ships in 1975 with the Sea Systems Modification
and Modernization by Modularity (SEAMOD) program.  The development of SEAMOD ships saved off-line
time, shipyard time and installation time for new technology and cost savings. This
was followed by Ship Systems Engineering Standards (SSES) program,
Affordability Through Commonality (ATC) program, Modular Open Systems Approach
(MOSA) concept and thereafter, the Architectures, Interfaces, and Modular
Systems (AIMS) program in 2003. Large numbers of warships including Destroyers were
built using these concepts. The vision of the AIMS program was to engineer a
ship with the concept called Modular Adaptable Ship (MAS). The MAS concept was
envisioned as the ideal implementation of a fully modular and flexible design,
which included modular zones with open, standard interfaces for most functional
areas of the ship. The work of the AIMS program directly led to the development
of LCS with open architecture systems and modular mission packages decoupled
from its sea frame. It also contributed modular and adaptable features to other
ship programs, such as the Ticonderoga, Arleigh Burke, and Ford classes11. This has been brought
out in the man-hour comparison table in chapter II. The goal of the LCS program
was to develop a near?shore
combat ship that could be developed at a low cost, and with a flexibility that
made it possible to rapidly shift from one type of warfare to another. It has different
modules that may be plugged in, providing capabilities such as Anti?surface warfare, Mine
Counter Measures, Anti?Submarine
Warfare, Intelligence, Surveillance and Reconnaissance, Special Operation
Forces support and Logistic support. These mission modules integrate to the
extent possible, into the sea frame’s command and control
architecture.  

Figure
5. LCS with replaceable mission modules

 

 

15.        
STANFLEX
Concept by Danish Navy. The
Standard Flex (STANFLEX) concept was created the Royal Danish Navy as a way to
reduce operating costs while still maintaining the fleet’s operational
capabilities. The STANFLEX concept12 envisaged a ship platform
configured to accept interchangeable combinations of modules13 depending on mission requirements
and a fleet composed entirely of these platforms.

 

16.        
SIGMA
Class of Ships by Damen Shipyard.   The Damen Schelde Naval Shipbuilding, Netherlands builds Frigates and
Corvettes to foreign navies on time and on budget using the Ship Integrated
Geometrical Modularity Approach (SIGMA)14. In this design, the hull
segments are modularized, and can be assembled in different numbers and
sequences, thus using a sectional modular approach. SIGMA vessels are designed
using standardised solutions with COTS equipment where possible, enhanced by
military standards where needed. This approach enables customers to compose
their own SIGMA design based on proven solutions. The shipyard, with manpower
of 9000 personnel delivers close to 160 ships each year to the world market.

 

17.        
The Modular Platform Concept (MOPCO)15
of the German shipyard Abeking & Rasmussen (A & R) is also based on
strict modularization of all systems and equipment which are  integrated 
in  an  improved 
design  of the  common 
platform with standard 
interface  connections.

 

18.        
Construction of Fleet Tankers for IN
by Fincantieri.    Warship construction at Fincantieri, Italy
was carried out using Zone-Oriented methods or Integrated Ship Building
Approach synergized with automatic welding system with robotic support.  Pre-outfitting was undertaken using Zone Outfitting methods which
disconnect the operations from the hull construction advancement. Hull block
construction and outfitting work were carried out simultaneously.  The work was undertaken in open spacious locations
with maximum safety and material handling benefits. The aft and forward
sections were constructed at two different locations namely Riva Trigoso and
Palermo respectively and integrated on Floating Dock at Muggiano16. The
construction of Deepak class tankers (two ships) was completed in 36 months and
ships were successfully delivered to IN
on time and on budget using modular construction approach.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CHAPTER
V

 

 

CONCLUSION

 

 

1.           
Indian defence shipyards are overloaded with
orders for construction of modern warships for the IN. Due to the various reasons mentioned in chapter II, like lack
of adequate infrastructure and technology, lack of proper planning
process,   non-supportive ancillary industry etc. the Indian
defence shipyards with their low productivity are not able to deliver warships
as per the requirement of IN. The
warships delivered by these shipyards are of the highest quality, which
indicates that capability exists in the industry, however there is lack of
capacity. Steps for modernisation of Indian DPSUs were initiated by the
government since the last decade; however, the progress has been slow and is not
considered sufficient to boost the productivity to meet IN requirements. The private defence shipyards are also facing
similar issues. The existing capacity constraints of Indian defence shipyards can
be overcome by implementation of the modular design and construction
technology.

 

2.           
The modular design and construction
technology is a highly effective technology which is successfully used by
leading shipbuilding nations in the world to reduce time and cost of warship construction.
In the modular concept, the complex warship is divided into blocks or modules
based on the functionality requirements, construction of these blocks are
carried out simultaneously at different locations and maximum outfitting in
shop floor is ensured using standardised components. These independent blocks
which are 60 – 90 % completed are then joined together in the dry dock or slip
way for trials and thereafter delivery to the customer. Modular concept would
help achieve synergies in procurement, integration, equipment and system testing,
and parallel ship hull construction; and also simplify complexities in future
upgrades.  The modular concept can be
modified with innovative inputs and can only be improvised further. Modular
innovative designs are outstanding hallmarks of over 50 proven robust, Corvettes
and Frigates operating in some of the world’s most savage environments.

 

3.           
 As
discussed in chapter III and IV, the successful implementation of modular technology
depends on various factors, both internal and external to the shipyards. It starts
with a good modular design which defines the level of modularity according to
which the construction of modules / blocks / mega blocks progresses. Today,
capability to design complex warships (with association of major equipment
manufacturers), is available only with the IN17. The DPSUs and private
shipyards in the country have not developed this crucial expertise because of
their dependency over the ages on the IN,
thereby restricting them from undertaking any value additions. Therefore,
Indian defence shipyards must develop a strong design bureau which would remain
a pre-requisite for the success of modular construction. Unlike conventional method,
the modular construction of warships is coupled with system engineering
approach, sufficient infrastructure and digitization of shipbuilding process. The
shipyards therefore would need to augment the existing infrastructure based on
the class of ships required to be constructed. Other areas include process
engineering changes, augmentation of design and manufacturing tools, effectiveness
of supply chain management, e-documentation, scaling up of design HR skills
etc.

 

4.           
Modular technology along with ‘build anywhere
– integrate anywhere’ concept would benefit in accelerating construction of warships
further with minimum interdependencies. The existing orders of DPSUs with
capacity constraints can be shared with private shipyards that have capacities
and limited orders. The strengths of both sectors of shipbuilding can be
exploited by using modular construction along with shared build strategy.  This strategy has been used effectively in the
US, France, Italy and the United Kingdom. This can help the shipyards to
overcome capacity constraints.

 

5.           
The benefits that modular design and
construction technology would provide to the Indian defence shipyards can be
concluded as follows:-

 

(a)         
Design
flexibility.

 

(b)         
Reduced
time and cost of construction with automated technology and standardisation.

 

(c)          
Reduced
man-hours due to modular outfitting and reduced work load when ship is docked.

 

(d)         
Clear
division of responsibility between the shipyard as prime contractor, suppliers
and manufacturers of weapons, electronic and machinery systems.

 

(e)         
Better
organisation and co-ordination of work between design and manufacturing hubs.

 

(f)           
Open
system architecture and standard interfaces reduce ship life cycle cost and makes
replacement / modification easier.

 

(g)         
Enhanced
quality of workmanship due to the assembly and testing of payload systems under
workshop conditions and at multiple sites across country.

 

(h)         
Saving
of time and costs for future upgrades and modernization of weapon and
electronic systems through quick and easy exchange of modules.

 

(j)           
More
opportunities for smaller businesses leading to a larger supplier base thus improving
quality and further reduced costs.

 

6.           
The modular technology has been used very effectively
for building warships by Germany using the MEKO concept, Damen shipyard in
Netherland using the SIGMA concept, US Navy by using MAS
concept and other leading shipbuilding nations like UK, Italy, Denmark etc. Based
on the successful implementation by these nations and considering the technological
superiority and benefits that modular technology offers, it is certain that correct
adoption of modular technology by Indian defence shipyards will help overcome
the existing capacity constraints and meet the requirements of IN. The shipyards would therefore need
to invest and realise the concepts of modularity from leading global
shipbuilders and imbibe the technological know-how of building warships.

 

 

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