Ship conversion Overhaul and Repair.pptx

Ship Conversion,
Overhaul and
Repair
Ship and Offshore Production Technology (NAOE 3215)

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Ship conversion, overhaul, and repair
The ship conversion, overhaul, and repair industry is
concerned with working on ships during their service
lives:
Changing their configurations so they can do better
jobs or different jobs
( conversion/modernization)
Generally and extensively bringing them back to an
almost like-new
condition (overhaul)
Maintaining the equipment and hull integrity of the
ship, repairing or replacing damaged and worn parts
(repair)

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Life Cycle of a Ship
A ship in service is subjected to operational wear, to
deterioration from exposure to harsh environments, and
to damage from heavy weather and unplanned
encounters with solid objects. The basic actions taken to
counter these effects and maximize the operational
readiness of the ship during its service life are illustrated
in Figure 9-1.
The scope of work and timing of each of these actions is
determined by one or more of the following:
(1) rules of the classification societies and regulatory
bodies,
(2) maintenance philosophy of the owner, and
(3) economic, market, and safety considerations.

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Planned Maintenance
This is a programmed cycle of regular, scheduled maintenance
and repair based both on direct inspection and equipment
failure history. It also includes periodic surveys by
classification societies and regulatory agencies.
Non-dry dock - frequent (usually annual) pier side
inspection and repair involving topside work where a dry
dock is not needed for access; also includes underway
maintenance
Dry dock - periodic major maintenance involving
inspection and repair of the underwater hull, propellers
and shafts, rudder, thrusters, hull coatings, cathodic
protection, sea chests, and other underwater items;
usually also includes all the work done in a non-dry dock
maintenance and small to medium sized configuration
changes planned for the ship (includes overhauls)

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Unscheduled Repairs
Unscheduled Repairs : This type of repair becomes
necessary when there is an unexpected equipment
failure or fouling, storm damage, collision damage, fire,
or any other event that compromises the safety of the
ship or its ability to perform its mission. It may require
dry-docking, depending on the nature and extent of the
damage.

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Conversion/Modernization
Occasionally as a ship grows older or market needs
change, it may make economic sense to the owner to
convert the ship for a different mission or to modernize it
to extend its service life. Conversion might involve
lengthening a ship with a new mid-body, changing the
bow, re-engining, changing the configuration to handle a
different kind of cargo, adding cranes for self loading, or
even changing a cargo ship into a hospital ship.
Modernization usually involves upgrading most of the
systems on a ship, including hull, propulsion, electronics,
and habitability to significantly extend the life of the ship
and meet the latest safety standards.

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Deactivation/Scrapping
At the end of the economical service life of a ship, the
owner has to determine how to dispose of it. This can
sometimes occur earlier in a ship's life if market
conditions change drastically and the ship is highly
specialized, such as a liquefied natural gas carrier. Some
ships, especially in the military, are deactivated and
stored for possible later use. Others are broken up for
the scrap or resale value of their materials and
equipment.

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Size and Scope of the Industry
Virtually all the new-construction yards also convert, overhaul,
and repair ships. As the ship construction market has
decreased, conversion, overhaul, and repair have become
increasingly important to most of these yards. Many have had
difficulty in adapting to the different requirements of the
repair market. These requirements feature a smaller overhead
organization, a multi-skilled, flexible work force, and the
ability to respond rapidly to emerging conditions that effect a
ship's operating schedule. Disruption of the planned ship
construction schedule sometimes occurs when urgent,
unscheduled ship repair work arrives at the shipyard and
competes for the attention of the best managers and
craftsmen. Construction yards sometimes use separate
facilities or organizational units for overhaul and repair activity
to avoid these problems.

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Size and Scope of the Industry
Virtually all the new-construction yards also convert, overhaul,
and repair ships. As the ship construction market has
decreased, conversion, overhaul, and repair have become
increasingly important to most of these yards. Many have had
difficulty in adapting to the different requirements of the
repair market. These requirements feature a smaller overhead
organization, a multi-skilled, flexible work force, and the
ability to respond rapidly to emerging conditions that effect a
ship's operating schedule. Disruption of the planned ship
construction schedule sometimes occurs when urgent,
unscheduled ship repair work arrives at the shipyard and
competes for the attention of the best managers and
craftsmen. Construction yards sometimes use separate
facilities or organizational units for overhaul and repair activity
to avoid these problems.

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Nature of the Industry
Conversion, overhaul, and repair jobs come in all sizes
and degrees of complexity. Each type of work may have
different facility, planning, and management
requirements depending on its size and complexity.
Facility requirements may range from portable tools to a
full-service shipyard; planning requirements from simple,
single system to complex zone technology; and
management requirements from functional, single trade
to sophisticated project teams working in a matrix
relationship with a full-service shop and support
organization. Matching the optimum approach with the
individual job will yield the most effective results.

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Similarities and Differences
There are both similarities and differences between ship
construction and ship conversion, overhaul, and repair.
Similarities include application of essentially the same
manufacturing and construction processes, using much
of the same equipment, tools, facilities, material, and
worker skills. The most important differences involve
time to complete the work and certainty of work scope.
Construction follows a carefully laid-out plan for a known
scope of work over a fixed amount of time. Conversion,
overhaul, and repair must accomplish a mixture of
known and unknown work on an already existing ship,
while minimizing out-of-service time for that ship.

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Out-of-service time for a ship
Out-of-service time for a ship is very expensive to its
owners. Thus rapid completion of work may be more
important to an owner than low price. This is especially
true in the cruise ship industry, where large crews of
service personnel and vast stores of perishable supplies
make operating costs so high. Much emphasis is placed
on creative approaches to minimize the ship's downtime,
e.g., use of riding teams to repair a ship as it continues
its route, use of the ship's ballast system to achieve
extreme heel or trim conditions to gain access to
underwater damage without having to go on a dry dock,
or removing equipment in one port and replacing it in
another.

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A major difficulty in minimizing a ship's downtime is that the
scope of the required repair work is not often completely
known. Inspections are conducted at sea, logs are kept, and
various maintenance philosophies implemented, but much
repair work always has to be identified after the job starts,
when the machinery, tanks, and other inaccessible places are
opened and inspected.
The uncertainty of the work scope means that the shipyard
needs an organization that can flexibly respond to on-site
information and resolve problems that may not become
apparent until the work is underway. This requires craftsmen
who are cross-trained and multi-skilled, managers working
within an empowered project management team, and a
flexible planning approach appropriate for the size and
complexity of the job.

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Marketplace Characteristics
The three primary markets in the conversion, overhaul,
and repair industry are for commercial ships, military
ships, and ships that are owned by the government, but
are built and maintained to commercial standards.
Owners of commercial ships are businessmen whose
purpose is to provide a service to people who are willing
to pay enough for that service so that the businessman
can make a reasonable profit. Therefore, except for the
classification society and regulatory agency
requirements, the drivers in this market virtually all
revolve around cost.

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Cost of ship maintenance and repair goes well beyond the
actual cost to have the work accomplished. It means the cost
impact to the overall operations. Often the most important
costs are caused by the out-of-service time for
the ship. These can include:
 Impaired service and loss of schedule credibility with
customers
 Loss of business anticipated in upcoming ports
 Providing opportunities for shipper's competitors to take
away customers and penetrate market
 Damage to on-board cargo if it is perishable
 Unproductive crew costs
 Un-defrayed overhead costs

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As can easily be seen, the decision on how much and how
often to repair and maintain ships can be a complicated
balancing act of competing needs. Of course, postponing
needed repairs can sometimes lead to more serious problems
that might result in even greater out-of-service time.
Frequently the naval architect or chief engineer for a shipping
company is responsible for giving the owner the technical
advice needed in this decision making process to balance one
type of cost against another.
The business side of this decision is made more difficult by
the intense competition in the shipping industry. The heavy
competition means less money available for all aspects of
shipping operations, including repair and maintenance.
However, the competition is also forcing new ideas and
technology, and entrepreneurs are finding ways to provide
better, faster, more reliable, and more secure service.

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Much of the routine maintenance work on a ship is done as
part of the planned maintenance program. The part required
by classification societies and regulatory agencies will be done
according to their rules. Other routine maintenance will be
done in accordance with the owner's maintenance program.
Such programs can vary widely, but will usually contain the
following:
 Record keeping on performance of major equipment
 Records of any equipment failure
 Records of all underway maintenance and repair
 Inspections by in-house engineers or subcontractors
 Definition of work package and development of specifications
 An invitation for bids from prospective
 contractors requiring both a fixed price
 and a promised delivery date.
 Selection of a contractor based on best
 Business judgment;

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Repair and maintenance programs for commercial ships can
be executed in many various ways depending on the owner's
maintenance philosophy, business approach, and the scope of
the work. Some shipowners prefer to perform as much of
their maintenance as possible with their own people. They
may have shops in strategic ports or teams that can fly with
their tools to wherever the ship is berthed. These teams may
perform maintenance tasks both in port and underway and
may prepare the ship in advance of in-port maintenance.
Some shipowners establish maintenance contracts with
companies that provide repair crews whenever necessary and
oversee shipyard contracts. They may also provide services
extended to include analysis of operating records, periodic
inspections, spare parts storage, and most other aspects of
managing ship maintenance programs. The maintenance
contracts may cover a single ship or a fleet of ships.

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Selecting an Approach
Ship repair is a classic example of the job shop form of
production organization. It is a Highly labor-intensive and skill-
intensive activity with only limited potential for automation.
Much of the work is done aboard ship, and consists of rip-out
and refitting steel, pipe, machinery, or wiring to existing
systems. The labor-intensive nature is also due to many parts
being manufactured or rebuilt in-house, instead of being
purchased new, as in ship construction.
Each job is unique, but to better understand how to approach
the many different types of repair situations we will focus this
discussion on the following factors:
 size
 complexity
 facility requirements
 planning approach
 management approach

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Approach selection criteria

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The size and complexity of a job serves as a guide for
choosing the most efficient approach to that job and, in
some cases, even limits which companies are capable of
pursuing the contract, as some companies specialize in a
narrow range of approaches. Large shipyards may find
that providing teams to pursue small emergency repairs
is disruptive and not economically feasible. Small
companies may find that organizing and managing a
large team to pursue major overhauls is too
cumbersome, financially risky. and difficult to control.
Rather than attempting to be all things to all people,
some companies try to be most competitive in a
particular niche of the market.

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Larger, more complex jobs tend to require more
extensive facilities and management organizations. They
also lend themselves to the use of some form of zone
technology approach and sometimes a limited amount of
group technology. Smaller, simpler jobs can often be
effectively executed with fewer facilities, less
sophisticated organizations, and on-the-job planning.
Where the threshold lies for using more sophisticated
planning and management approaches is a matter of
judgment, resulting from an evaluation of each job, as
shown in Figure 9-5.

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The size and complexity of a job serves as a guide for
choosing the most efficient approach to that job and, in
some cases, even limits which companies are capable of
pursuing the contract, as some companies specialize in a
narrow range of approaches. Large shipyards may find
that providing teams to pursue small emergency repairs
is disruptive and not economically feasible. Small
companies may find that organizing and managing a
large team to pursue major overhauls is too
cumbersome, financially risky. and difficult to control.
Rather than attempting to be all things to all people,
some companies

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The outside machine shop serving the machinists working on
the waterfront, the pipe shop, or the electrical shop may
assume a priority role. Services to piers and docks assume a
greater importance because, in addition to supporting
shipyard workers, they are also used to keep many of the ship
systems on-line during the repair activity in support of the
ship's crew.
A full-service shipyard may include a range of dry-docking
capabilities, such as:
 Large graving docks capable of servicing VLCCs, ULCCs,
aircraft carriers, and other large vessels
 Medium-size graving docks for dry docking medium and
small ships, sometimes more than one at a time
 Floating dry docks for smaller ships and submarines, and to
enhance the capability for joining bows, sterns, and
midsections on ships

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Pier berthing should be equipped with flexible crane
service and access, adjacent staging areas, and
convenient access to fabrication and inside repair shops.
A full range of pierside services would also provide
power, high-pressure air, steam, fresh water, waste
handling, fire mains and pumps, oily water removal and
reprocessing, and environmental protection services.

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Shop capabilities and facilities would include:
 pipe shop with pipe bending equipment
 steel fabrication shop with numerically controlled
burning machines and with plate bending capability
 blasting and priming facility
 sheet metal shop
 electrical shop
 machine shop with CNC capability
 computer-aided design and manufacturing (CAD/CAM)
capability

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So-called topside companies typically have only shop
facilities, with no waterfront facilities at all. These
companies have mobile teams with fleets of trucks
equipped to do many types of repairs. They use
sophisticated portable communication systems and
specialize in rapid turnaround work on operating ships.
Sometimes they have facilities at more than one port
along a common shipping route, allowing them to
provide coordinated service all along the route with
equipment removal at one port and reinstallation at a
subsequent port. They may participate in larger jobs by
teaming with other shipyards or specialty subcontractors.

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Planning Approach
Planning for conversion, overhaul , and repair has
traditionally been based on ship systems. However, as
zone technology has been increasingly implemented in
ship construction, it has also been adapted for use in
conversion, overhaul, and repair where it is justified by
the size and complexity of the work. Within a zone
approach, group technology (GT) with a product-
oriented work breakdown structure (PWBS) focuses on
developing repeatable work processes whenever
possible, even when applied to considerably different
ship designs.

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System Approach
The traditional systems planning approach begins with initial
identification of the repair requirements by systems.
Operational logs are kept by system; component failure
statistics are kept and evaluated by system; and in-service
tests and inspections are done by system. Then cost and
material estimating are done by systems, because that is the
way the work is defined. Scheduling and authorization of
production tasks are done by system and by trade. This works
out neatly for the planners and schedulers because traditional
shipyard trades are organized to work on systems of only one
type (pipe, electrical, ventilation, etc.). Finally, testing is also
accomplished by system.

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Planning Approach
Scheduling by system is usually done in two stages.
During the first stage, the basic elements-removal,
inspection, repair (shipboard or shop), reinstallation, and
test-are given approximate start and stop dates, and a
few intermediate milestone dates are established.
Preliminary information on scope and historical data are
used to estimate total time-phased manning profiles and
material requirements. In the second stage, more
detailed project scheduling is accomplished, work
packages are written, a critical path method (CPM)
network may be constructed, and man loading is refined.
Networks drawn on a system-by-system basis generally
result in a series of parallel lines which, in theory, are
interconnected at each system interface.

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Planning Approach
Figure 9-8 is a simple example of a network based on system.
Components (valves and pumps) are to be removed and repaired,
the pump foundations modified, electrical cabling ripped out and
modified, and the system put back together and tested. Each of
these operations is assigned a target time and resources for
completion. The circles specify events or milestones that must be
realized prior to proceeding to the next set of operations.

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Zone-Oriented Approach
Creating zones is simply a convenient device for aggregating tasks
in the most appropriate way for the tasks to be performed at any
given stage of the job. Where the task is simple and confined to
one system, a zone could be created for that system, meaning
zone would equal system in that case. Where jobs are more
complicated and work is focused in specific areas like the engine
room, the auxiliary machinery space, or the bridge, geographical
areas might make more sense as zones within a particular phase
of the entire job. A zone can be a compartment on the ship, only
part of that compartment, a group of compartments, a system,
part of a system, a group of systems, or a prefabricated unit being
built in a shop. It can be any collection of tasks grouped logically
for efficient performance. As with product-oriented new
construction, sequencing is done in terms of problem areas and
stages within a problem area. One component might even be part
of different zones at various stages of the work.

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Planning Approach
Zones are generally considered to fall into the following
three categories:
 geographic area
 functional area-subdivision of the ship that includes all
equipment associated with a particulasry sytem or
component, such as all piping and pumps associated
with a particular tank, as well as the tank itself
 variable zone : combination of functional zone and
geographic zone that organizes the work by process,
also known as a work zone.

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Zone Approach
A stage is a substep or a band of time during an overhaul in
which specific production processes take place. Examples
include:
 pre-arrival planning, engineering, and scheduling (Pre-
arrival preparation is being expanded by some owners and
shipyards to include underway layout, open and inspect,
and rip-out wherever possible to reduce downtime for the
ship during repairs.)
 prefabrication
 disassembly (rip-out)
 open and inspect (re-planning and engineering)
 repair or modification
 on-unit assembly
 on-block assembly
 on-board assembly
 testing
 trials

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Management Approach
The traditional approach to ship repair management has been by
function. This was because the work definition, design, estimating,
purchasing, planning, and testing were all done by systems, the
same systems that were the exclusive responsibility of specific trade
skill functions.
The pipefitters did pipe systems, the shipfitters built hull structures,
electricians ran wire and hooked up electrical equipment, machinists
worked on machinery, and the sheet metal workers did ventilation.
This approach can be effective for smaller, simple jobs involving only
a few systems. However, when the scope of work becomes too
large, the work spaces too congested, or the work too complex or
involving too many systems, this trade and system approach to
managing a project frequently results in competition between
different trades for work space and resources. The trades‘ primary
concern becomes the success of their individual trades, not the
health of the overall project.

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Management Approach
For these larger, more complex situations, there is a need for an
approach that allows a manager to step back and view the project
as a whole and make decisions based on the overall good of the
project, not a single trade. When this manager puts together a
project management team with representatives from each of the
major trades and support organizations, he or she has the tools for
coordinating all the project work to meet the overall project goals.
All shipyard shops and departments are expected to support the
project team and to provide trained personnel and equipment as
requested and funded by the project team.
The project team is structured to take advantage of the zone
technology applied in the planning approach. Zone managers are
identified and tasked with the proper planning and execution of all
work within their assigned zones and they are responsible to the
project manager for their daily performance.
The project team approach greatly facilitates the planning of
integrated work flows by promoting discussion. tradeoff. and mutual
consent between the project team members.

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Repair and Overhaul
A ship needs to be operating to earn money for its owner or, if it is a
military ship, to perform its mission. In order to maximize operating
time during its service life, a ship must be repaired when damaged
and maintained regularly to avoid breakdown and deterioration.
Classification societies publish rules for maintenance of the vessels
they classify. Surveys are conducted at intervals, with the type of
inspection varying with the age of the ship. In addition to regular
surveys, the societies require that damage repairs be accomplished
according to society rules. In addition to classification society
inspection, government agencies inspect merchant vessels to assure
that they are maintained according to published rules.
Repair and maintenance of ships generally falls into three
categories discussed below:
 unscheduled voyage repairs
 planned maintenance
 overhauls

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Unscheduled Voyage Repairs
The need for unscheduled voyage repairs results from damage or
breakdown occurring during operations. Damage can come from
exposure to heavy seas and weather, collisions, groundings, fire,
explosions, or flooding. Breakdowns and other equipment failures
can occur at any time. Whenever one of these events does occur
and the ship must be repaired, it is an emergency, affecting the
ability of the ship to operate safely and perform its mission.
Emergency repairs require immediate attention; otherwise they
would be postponed until a more convenient time, preferably the
next planned maintenance period when the work could be bid as
part of a larger work package to keep the cost down.
Even when there is competition, emergency repairs tend to cost
substantially more than routine maintenance. This is because the
emphasis is on placing the ship back in service as quickly as
possible. The cost of the ship being out of service is generally much
more than the cost of the repairs. Therefore, there is an economic
incentive to find ways to minimize out-of-service time or even
accomplish repairs with riding crews to avoid it altogether.

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Fire in a combat information center of a military ship is less
likely to be encountered. It is, however, an example of
damage that might not be great in size, but be very complex
and affect many systems on the ship.
Facilities-This work can be done at pierside. It does not have
to be a shipyard pier, but it would be preferable to have the
ship near the shops, shipyard crane, and other material-
handling services. An electronics shop will be needed, though
some of this work may be subcontracted. There will be some
structural work requiring steel and perhaps aluminum
fabrication and welding facilities. The ventilation, pipe,
electrical, and joinery shops will also have tasks to do.

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Zone planning approach -While the fire may have been
confined to one space, it damaged the controls, monitors, and
wiring for systems that go all over the ship, as well as the
many support systems serving that space. It might make
sense to divide the burned-out space into zones that would
change by stage. One set of zones might make sense for rip-
out, another for structural repairs, and yet another for
equipment installation and wiring. Since much wiring is sure
to be damaged and some types of wiring are not allowed to
be spliced, there may be a requirement to rerun electrical
cables to many places throughout the ship which could also
be one or more zones. Finally, a system approach is used for
the massive test and certification program.

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Project management approach: The job will involve many
trades, the services of original equipment manufacturers, in-
house electronics experts (or, more likely, subcontractors)
certification agencies, and an intricate, extensive test
program. It will be necessary to coordinate the many people
from different trades and companies. All working in the
confined space, to ensure that they can get their jobs done
effectively without compromising the goals of the overall
project. Creative approaches may have to be used to get
long-lead-time material more rapidly than usual. This
definitely calls for a sophisticated project team, but not
necessarily a large one.

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The last case is the most extreme one. Before repairing a ship
that was in a serious collision and suffered a major engine room fire,
the owner would have to consult with the insurer to determine
whether it makes economic sense or whether the ship should be
scrapped. Damage in this scenario could take a year or more to
repair and include gutting the engine room, re-engining the ship,
replacing support systems, installing new switchboards and wiring,
renewing much of the structure, and probably performing other
work throughout the ship. An owner might take advantage of this
situation to modernize the ship or even convert it, if the market and
economic conditions called for it. The extent of this type of
unscheduled repair is most analogous to conversion and
modernization.

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Facilities: This work requires a full service shipyard, including a dry
dock.
Zone planning approach: A project of this size and complexity
needs the same type of sophisticated zone approach used for
conversion and modernization. The main differences would be the
additional zone structure set up for the extensive removals and the
greater amount of work scope that remains unknown until the
removals are made and an in-depth survey is completed.
Zone management approach: A job of this nature requires the
most sophisticated project management team working with a large
shipyard work force in a matrix relationship. The project team
should include members from all the major shipyard organizations to
coordinate planning, material ordering, prefabrication, production,
subcontractors, testing, and contract management.

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Planned Maintenance
By definition, planned maintenance is not emergency in
nature. It is based on mandated surveys by the classification
societies and regulatory agencies, inspection logs and
performance records of the operator, and a regular
maintenance program run by the owner based on his or her
own maintenance philosophy, statistical information on
equipment failure rates, or predictive data collection. All these
programs are designed to keep ships operating safely with a
minimum of downtime.

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Planned Maintenance (case study)
In order to maintain their initial classifications, steel ships are
usually surveyed annually. At pierside, the condition of hull closure
appliances, freeboard marks, and auxiliary steering gear is inspected
by a representative of the classification society. Concerned with
safety, regulatory bodies check out stability, fire protection,
machinery and electrical system safety, hazardous and polluting
substance control, lifesaving equipment, and navigation and
communication equipment. Planned maintenance and repairs are
accomplished, usually under a contract with a shipyard or a topside
repair company and may last from a week for some commercial
ships to several months for a military ship. Sometimes preparation
for the in-port planned maintenance is done at sea with a riding
team to reduce the required time in port. This is done frequently on
cruise ships because of the high cost of having them out of service.

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Planned Maintenance (case study)
Facilities-This work can be done at any pier, but is more
convenient in a shipyard with access to cranes, shops,
and controlled staging areas. Otherwise, workers, tools,
and material have to be transported to and from the job
site daily.
Zone planning approach-Work is done throughout the
ship and is best coordinated using zone technology, since
there is time for a well-thought out approach.
Project management approach-A small project team can
handle most jobs of this magnitude, especially since the
members can participate in the early planning.

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Overhaul
Overhaul is a special larger-scale type of planned
maintenance. Its purpose is to bring the overall
operating condition of a ship back to good-as-new, as
well as to perform all the work in Section 3.3.2. While
major ship alterations may be performed (such as adding
new weapons systems to a Navy combatant), overhaul is
usually concerned with making the same systems work
like new, not replacing them with more modern ones.
However, overhaul is similar in many respects to
Conversion and modernization( discussed in the next
section), especially in the planning and management
approach.

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Overhaul
Overhaul is a large and complex undertaking, lasting
from a few months to a year for many military ships.
Appropriate planning and management approaches
always involve zone planning and a project team.
Case 2. Overhaul of merchant ships and noncombatant
military ships is substantially larger in scale. These ships
have propulsion, auxiliary, cargo handling,
communication/navigation, and habitability systems to
be overhauled throughout the ship. Much of the
equipment will be removed to shops for repairs and
component testing. A major challenge is putting the ship
back together again after having it in such a state of
disassembly.

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Overhaul
Facilities-A dry dock, pier, cranes, and a full array of
repair shops are required for an overhaul of this nature.
Secure storage areas for both new and removed ship
material are needed. Office facilities for the project team
should be provided adjacent to the job site with a clear
view of the ship and its access points.

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Overhaul
Zone planning approach-
A zone technology approach is certainly dictated by the
magnitude and diverse location of the work. However, it is
also made necessary by the complexity of reassembling the
ship with material and equipment that have been removed
from the ship and stored, removed from the ship to a shop
and repaired, removed from the ship and sent to a
subcontractor for repair, bought new or manufactured, or
provided by the owner. Accountability for this great amount of
material and equipment must be maintained throughout the
process, and the material and equipment must be returned to
the ship in time to support the reinstallation Sequences and
phased testing program. Each piece of equipment or material
must be linked to its location and its place in the process by
zone and by stage.

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Overhaul
Project management approach-A job of this nature
requires a sophisticated project management team
working with a large shipyard work force in a matrix
matrix relationship. The project team should include
members from all the major shipyard organizations to
coordinate planning, material ordering, prefabrication,
production, subcontractors, testing, trials, and contract
management.

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Conversion and Modernization
Conversion and modernization of both commercial vessels and
naval warships are complex strategic, business, and
waterfront production endeavors. Typical modernization and
conversion projects include installation or removal of mid-
bodies, cargo-handling upgrades, installation of improved
bows, re-engining work, habitability upgrades, environmental
protection modifications, and military mission system
upgrades. Figure 9-24 shows the conversion of an old tanker
for continued use. This process, termed "jumboizing,,‘ utilizes
the stern, machinery room, and existing house. Completely
new (and usually larger) cargo tanks, pump room, and bow
are joined to the stern, providing an additional 15 to 20 years
of service to the ship owner at lower cost than completely
new construction.

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These types of projects are often technically challenging and
require a substantial engineering effort. Conversion projects
are also characterized by high material and equipment costs
and labor-intensive rip-out and installation. Items such as a
new missile system for a modern cruiser, a new main
propulsion unit in a re-engining effort, or steel for vessel
lengthening are major expenditures. In some cases,
installation cost is much more than it would be in a new ship
where installation could occur at a stage of construction when
there was easy access Rip-out, working around existing
systems, transporting material through circuitous access
routes, and additional safety precautions necessary for
working around such hazards as fuel oil and live electrical
systems force up labor costs substantially.

61
Whether to undertake conversion and modernization
work is fundamentally a strategic business decision that
may be considered several times during the life of a ship.
This decision is influenced by external drivers (see Figure
9-25) that are similar for the private ship operator and
the naval planner. Both consider and respond to
competition and external threats, technological
developments, changing mission requirements, and the
age and material condition of the ship.

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The modernization/conversion decision is influenced by
labor prices, material costs, government regulations,
replacement costs, and competitor decisions and actions.
The decision maker is ultimately faced with conducting a
series of cost-benefit analyses on the various
scenarios:
 Do nothing and continue to operate the ship as
currently configured and in the same mission status.
 Scrap the ship and build a replacement vessel.
 Conduct the conversion or modernization project.

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As an example of this type of decision making, consider the
recent actions of a major ship owner reacting to new
government regulations, changing market conditions, and
actions of competitors. The vessel in question was built in
1975 and was used primarily as a crude oil tanker until 1992.
In September of that year, the U.S. Coast Guard ruled that the
ship owner would be required to conduct major repairs and
upgrading if he were to continue to operate the ship as a
crude oil tanker. These requirements were based on new
safety and environmental regulations. The current oil-shipping
market did not justify the capital investment to conduct the
required upgrades, so the owner decided to alter the mission
of the ship, employing it exclusively as a carrier of
government grain cargoes.

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The aging of the world fleet is producing a need for
more modern shipping capacity and forcing more of
these types of decisions.. Fleet data are constantly
reviewed by shipbuilding and repair marketing personnel
in order to determine the demand for conversion or
modernization versus new building. Since new building
costs are high and world trade prospects continue
strong, service life extension alternatives to new
construction are attractive to a large number of ship
owners and operators and are expected to provide
continuing modernization and conversion work for shin
repair companies.

65
Complexity is initially confronted during the basic and
functional design processes for the proposed conversion
or modernization, demanding creative and innovative
solutions. During basic design, specifications that
address the technical and performance requirements of
the conversion or modernization project are developed.
From these specifications and requirements, system
diagrams and zone groupings are developed as part of
the functional design process. These processes are very
similar to those encountered during basic design and
functional design on a new construction project, but are
frequently more complex because of the following
factors:

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 Size and space considerations on the existing vessel
 Support system requirements for the new equipment
 Compatibility issues with other equipment that will
remain on the ship.
 Weight, moment, list, and trim limitations
Complexity in a conversion or modernization effort is
addressed during the planning and execution of the
project in some of the following ways:

67
 Identifying and segregating material into material-
ordering zones and establishing appropriate linkages
to the work control schedule
 Establishing zone boundaries and appropriate zone
groupings
 Establishing appropriate linkages with the fabrication
shops
 Planning, establishing, and maintaining proper flows
of work
 Implementation of the zone-oriented organization and
zone-oriented scheduling

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 Developing schedules that are resource based
 Integrating zone production schedules with system
testing and certification requirements
 Planning and scheduling unique or high-value
resources
 Estimating, costing, and progressing work via zone-
oriented approaches
 Bench marking costs versus potential competitors
 Performing make or buy decisions
 Subcontracting or outsourcing portions of the project
to reduce cost and speed up schedule

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Conversion: Case Study
Conversion of a double-hulled Aframax tanker
to a shuttle tanker
The primary conversion work on this double-hulled tanker
included installation of a bow loading system, bow and stern
thrusters, controllable-pitch propeller, an additional diesel
generator, a dynamic positioning system, and additional fire,
safety, navigational, and communications equipment. The
requirements were straightforward, employing commonly
used equipment. The location of this equipment was designed
to preclude any major access or interference problems.
Overall, the job was moderate in size and not particularly
complex. The project was completed in 60 days and the
tanker was transformed into a full, dynamically positioned,
shuttle tanker.

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Conversion: Case Study
Conversion of a double-hulled Aframax tanker
to a shuttle tanker
The conversion of a MarAd container/Cargo ship to a self-
loading crane ship was a major initiative at two successive
shipyards. The primary conversion work on the project
included installation of two Hagglund model 3637 crane
systems, including building new support structure all the way
to the bottom of the ship. Other major work included new
diesel generator installation, new switchboards and electrical
wiring the length of the ship, new after-crane, LP turbine re-
bucketing, boiler repairs, cargo hold modifications, installation
of permanent ballast in 10 tanks, rerouting of all tank piping,
cargo hatch cover repairs and preservation, hull repairs and
painting, and substantial tank repairs

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The conversion was a technically demanding project, because
weight, moment, and trim considerations were major factors
in the installation of the two large cranes. Complete support
system evaluations were required, especially in the areas of
electrical power and hydraulics. This project was made much
more difficult by being started at one shipyard, being stopped
by the government due to funding problems, and having the
ship laid up for two years with all the systems open and the
new cranes stored in the wet cargo holds.
The ship was finally brought to the second yard in a
deteriorated condition with the removed material scattered
about and the work scope unknown. This job was considered
large and much more complex than it should have been. The
project was completed in 20 months at the second yard.
Conversion: Case Study: Conversion of a double-hulled
Aframax tanker to a shuttle tanker

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Service life extension for a U.S. Navy aircraft carrier
Case 6. Because of their tremendous cost, aircraft
carriers are designed to last longer than most other
ships. The aircraft carrier Service Life Extension Program
(SLEP) projects were designed to extend the service life
of the Forrestal class aircraft carriers even further (from
30 years to 45 years). These huge modernization
projects were challenging simply because of the sheer
scale of the effort. They were so big that in the initial
zone breakdown (shown in Figure 9-28), each zone was
called a mini-ship.

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Communications equipment, radar systems, avionics, fire
control systems, and weapons elevators were all modernized.
Catapults, arresting gear, jet blast deflectors, and aircraft
elevators were all overhauled. Major propulsion systems were
overhauled, as well as numerous tanks, voids, pump rooms,
and the underwater hull. Space and access considerations
were difficult. A comprehensive review of all support system
requirements was necessary due to the large number of newly
installed components and the radically changed system
configurations.

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Another vital consideration in the new systems designs
was that they would have to support future
modernization projects with increasing demands. The
ship would now operate well into the next century and
would be required to face new threats and changing
mission scenarios. This project was considered to be
massive and very complex. The duration of a SLEP
project is approximately 28 months. To date, all SLEP
projects have been accomplished only at naval
shipyards.

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