How Is A Shipyard Designed?

Introduction 

While ship design involves many complexities, it is no wonder that the design of shipyards that cater to the construction of diverse vessels like ships or submarines over the years, housing the entire hierarchy of workflow starting from plate preparation to launching, is convoluted as well. 

Now, when we pose the question: What should be the exact design and layout of a shipyard, the answer is very vague. This is because shipyards or shipbuilding facilities and the vessels being produced follow a linear relationship based on size, type, service, and complexity. 

A small shipyard, with limited capabilities, can only be utilized for the fabrication and construction of simpler vessels with lesser deadweight, and larger shipyards with advanced architecture and infrastructure are equipped to handle larger and more complex vessels, also more in number and often in tandem, depending on the work order book. 

The functional position of the shipyard as a production asset also plays a crucial role. For instance, defence shipyards or shipbuilding facilities in large economies often need to deliver a significant number of work orders within stringent timelines. Similarly, for instance, small or medium-sized shipyards can do away with a single work order for months and even years. Likewise, for a large commercial shipyard, when there is a lineup of large vessels like tankers or bulk carriers, the time taken to build and deliver on such vessels is far more than when there is an order log of small ships like tugs or patrol vessels that can be fabricated in a lesser span of time. 

Feasibility Study and analyzing the requirements

The very first stage in the design of a shipyard is analyzing the requirements as follows: 

• Type of vessels to be built 
• Size of the vessels to be built 
• The maximum deadweight of the vessels to be constructed 
• Nature of the work order requirements.

Optimizing all the above, the feasible size and complexity of the shipyard to be built is decided. 

Costing, Budgeting, and Planning 

At this juncture, the costing and budgeting part, considering the profit-loss estimate cycles and worth assessment metrics, comes into play where an estimated plan is proposed for the entire project along with man days, resourcing, and the average time expected to be required as per the valuation framework. 

Land acquisition for the shipyard is finalized optimizing the maximum area of the land that is available and all contributing factors that provide the perspective of the demand that is needed (vessel size, type, sector, and feasible production competence that is anticipated). 

The land area now essentially sets the boundary conditions in terms of the maximum available extent within which the ensured facility needs to be designed.

Deciding the location

Shipyards always need to be situated at strategic locations. 

Once the area limits are decided, the next stage is to zero down on the location. Selecting the location takes into consideration important factors about vessels plus some other ambits. 

The aforesaid parameters related to the vessels to be produced determine the heads such as: 

• Depth and bathymetric considerations (for draft allowances) 

• Waves and tidal variations 

• Sedimentation and other coastal processes affecting the launching and repair of ships 

• Underwater geography and topology

• Nature of currents 

The commercial factors that are considered are:

• Proximity to supply chains (for raw material procurement) 
• Railroad and roadway connectivity 
• Vicinity to any trade or commercial hub such as a big city, port, or special economic zone. 
• Convenience of manpower allocation 

Apart from the above two heads, the other miscellaneous factors considered are: 

• No loss of human habitation and livelihood (like fishing and aquaculture) 
• Minimal damage to the environment and natural ecosystems 
• Meteorological patterns prevailing in that region
• Geopolitical conditions 
• Other aspects like safety, security threats to assets, potential interference with waterways, etc. 

Preliminary Design 

After assimilating the primary data about feasibility studies, requirements, size, and location, the next very important step is preparing a primary tentative plan or initial layout of the facility. This includes a rough blueprint in terms of how the shipyard is supposed to appear such that it is capable of not only catering to the requirements but also reducing production downtime in the best way. In the commercial shipping industry, time is money, and in the defence sector, time is security and power. 

This is a complicated and iterative process that is based on the optimization of the inputs in the best manner possible. Often large shipyards in the past and present have relied on traditional numerical methods based on first principles and complex logic to come up with the maximum optimized plan.

Thanks to the surge of modern computation, the data revolution, and the waves of AI and ML, these conventional methods are soon transcending to automated means based on data and cyber-intelligence where not only human intervention is considerably reduced but also the overall arrangement optimized to suit to the best feasible standards productivity and efficiency. 

Now, these inputs commonly used are culminated from the above discussion: 

•   Area and Geometry of land which essentially serves as the boundary condition.
•  Vessels are expected to be constructed in the lifecycle of the yard (type, size, and number).

The number is taken as an estimated lifetime maximum without considering time-varying factors like order fluctuations owing to a host of factors like economic booms or recessions, inflations, defence resizing, change of the country’s stature in world rankings, market and supply chain transformations, manpower changes, etc. 

These, in turn, decide the following: 

• Geometry and block size of the ships to be constructed 

• Production volumes

The output of this preliminary design stage is in terms of the best feasible configuration of the various units that take part in the shipbuilding process: size of the units, arrangement, distribution, and number. 

For instance, for a shipyard layout suited for large target production volumes where there is some constraint in terms of the shoreline limits available, the dry dock spaces need to be designed in such a way that they can handle multiple vessels at the same time to accommodate a bigger number in case the situation of the order book demands. In this case, the dry dock units, other than being sufficient in width to cater to wide-beam vessels need to also be long enough such that multiple vessels can be lined up before delivery or launching. 

Similarly, for a small or medium-sized shipyard that has limited space for a separate plate preparation shop, the plates need to be procured externally. However, the facility should have sufficient provisions for stowing, marshalling, and other jobs like welding or cutting of the plate stocks being procured. 

The economic question is investigated next. In the above example, the plate yard for stowing and preparing the plates is located such that the cost and time incurred in transferring the fabricated plate stocks are optimized to a minimum. Similarly, the modular block units are strategically arranged in such a way that the downtime and complexity in welding the individual vessel blocks are assuaged to the highest extent. 

The detailed process and methodology for optimization are complicated, mostly theoretical, and beyond the scope of this article. The main three aspects considered for the disposition of the various units and workstations are: 

• Area or space calculation 
• Locations
• Relative arrangement concerning the overall workflow of vessel production and inter-operability

Basic, Detailed and Contract Design 

After the preliminary design is finalised, the next phase is the basic design. At this stage, the concept design is further refined to have a clearer picture of how the intended design is to suit the objectives of best practice in terms of production volumes, lowest cost indices, least downtimes, minimal bottlenecks in the workflow, safety of personnel, and of course, the desired benchmarks of quality that is the primary goal of any shipbuilding facility. 

In modern shipyard design processes, computational or artificial simulations are often carried out using virtual environments. For instance, it is assessed how a particular shop or unit can cater to the actual sizes and types of ship blocks that are going to be fabricated, also keeping in mind maximum volumes. 

Likewise, several modes of feasibility analysis studies are carried out about how the fitting-out jetty or the drydocks can conform to the highest considered log book statuses when there is a pressing need to launch and deliver multiple vessels in limited time frames. 

The following stage is the detailed design stage when the definition of the shipyard is done at a granular level. 

These include activities like: 

• Designing each unit and space at a detailed level (size, number, layout). 
• Layout the configuration of each production and assembly line.
• Define the final location of all sections ranging from a small paint shop office to the modular hull units. 
• Determine the proper equipment and systems required like cranage types, automated machines, welding lines, painting devices, etc. along with their specific particulars and dispositions. 
• Prepare a proper plan for the typical sequence of workflow and the downtime each segment is required to take till the launching of the vessel.

Contract design is the last stage where the total blueprint design of the shipyard at micro levels is ready to be handed over to third-party stakeholders with separate responsibilities for materializing the final infrastructure as per the proposed costing and timeline determined. 

You might also like to read-

• 10 Major U.S Shipyards Where Ships Are Built
• Types of Shipyards Explained
• Different Jobs in a Shipyard & Shipbuilding Industry
• 11 Steps that Ensure Occupational Safety and Health in a Shipyard
• 8 Main Hazards Faced by Shipyard Workers

About Author

Subhodeep is a Naval Architecture and Ocean Engineering graduate. Interested in the intricacies of marine structures and goal-based design aspects, he is dedicated to sharing and propagation of common technical knowledge within this sector, which, at this very moment, requires a turnabout to flourish back to its old glory.

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