CLASS No 8 MODERN SHIPBUILDING PRACTICE and SHIPYARD LAYOUT & EQUIPMENT

CLASS No 8 MODERN SHIPBUILDING PRACTICE AND SHIPYARD LAYOUT & EQUIPMENT

8.1 KEY CONCEPTS: . Shipyards should be close to and have access to the open sea, and road and/or rail system should be suitable for delivery of equipment, components and raw materials. . Shipyards should also be located where there is adequate educated and trained people. . At least one boundary should be adjacent to the water. . Shipyards require the following attributes: - Warehouses and raw materiel storage areas - Shops to fabricate and assemble parts into sub-assemblies, assemblies and even outfitted blocks - Building berth and system of transferring ship to water- launchway, drydock, floating dock - Pier(s) to secure the ship after launch . Goals of facility layout that must be considered are: - optimizing material and work-in-process inventory - minimizing buffer storage consistent with uniform flow throughout the yard - minimizing the number of lifts and reducing the distance material and interim products must be transferred. . Block Construction and Advanced Outfitting require greater lift capacity cranes. 200T Whirleys and 1000 T+ Gantrys. . Most U.S. shipyards have been in existence for many years and are constrained by existing plant boundaries and layout. . Both steel and ship throughput are important criteria. To be internationally competitive, a shipyard requires a minimum of 60,000 tons of steel and 4 ships per year.

COURSE NOTES: . Papers on shipyard layout and equipment . TTS and IMG Equipment Catalog Sheets . PDF file: shipyard_layout.pdf (19Mb) (text only) CLASS No 9 MODERN SHIPBUILDING PRACTICE

KEY CONCEPTS: . Modern shipbuilding practices are not new, they have been around for 20+ years. . The key today is to integrate and implement them in a way that improves productivity and delivery time. . Most world class shipbuilders use the Block Construction, Zone Outfitting approach. . Successful world class shipbuilders have developed the approach into a stabilized flow of information, material and people. . The most important factor is the organization of the work. This includes: - The development of a Shipbuilding Policy and use of Build Strategies - Technical documentation format suitable for direct use by Production - Use of work stations and work station documentation and planning - Highly trained workers - Decision making/planning delegated to appropriate level - Early involvement of Production in the design process - Concurrent development of product and process design

. The major difference in large shipbuilding is the approach to block erection. U.S. shipyards typically handle 200 to 400 ton blocks. This means that they can have up to 160 blocks to erect on the building berth. World class shipyards all construct GRAND BLOCKS which weigh 1000 to 2000 tons. They are either lifted onto the building berth by 1000+ton Gantry Cranes or moved into place by transported and/or elevators. . The shipbuilding process consists of fabricating raw material into ship parts and assembling them, along with purchased equipment and components (interim products) to produce the finished product, namely the ship . All shipyards have the same basic processes

COURSE NOTES: . PDF file: shipbuilding_practice.pdf CLASS No 10 DESIGN FOR PRODUCTION

.All design should be prepared to suit a shipyard's facilities and preferred production methods .It has been necessary to develop the DFX approaches because designers have not stepped up to this responsibility .X covers, Production, Manufacturability, Maintainability, Assembly, Cost. .DFP takes into account production methods and techniques that reduce the product work content, but still meet the specified design requirements and quality .DFP must be incorporated into a design from the start .Traditional engineering leaves it up to another department, such as Production or Manufacturing Engineering to develop the technical documentation required by the Production workers. This is an un-necessary duplication of effort and is a non-value added task that takes time .An objective of the new (relatively) Concurrent Engineering approach is to accommodate DFP by bringing all the necessary people together right from day one on a project .The time to influence the cost of a product is during the early stages. After the design has been develop in concept most of the opportunity to positively affect cost is gone .World class ship designers know how their shipyard builds ships and designs accordingly. U.S. ship designers usually do not consider this and the designs may or may not be efficiently built in their facilities. More U.S. shipbuilders have taken steps to remedy this situation through the use of the Build Strategy approach .Engineering should be prepared and transmitted to the users in a way that best suits block construction, advanced and zone outfitting

COURSE NOTES: .Paper, "DESIGN FOR PRODUCTION IN BASIC DESIGN," by T. Lamb .Paper, "ENGINEERING FOR SHIP PRODUCTION," by T. Lamb .PDF file: design_for_production.pdf

CLASS No13 CAD/CAM APPLICATIONS & SIMULATION BASED DESIGN

.Computers were introduced to ship design in the early 1960's .Naval Architecture and Marine Engineering calculations were the early applications .Computer application to hull fairing started about 1963 .N/C machine tools introduced in U.S. in 1954 .British Oxygen developed N/C Burning Machine in 1959 .Computer applications move in two directions - CAD and CAM .There are both generic and industry specific CAD/CAM systems .By 1985 integrated CAD/CAM Shipbuilding systems are available .Improvements since then have been in user friendliness and modeling .Today there are a number of shipbuilding specific 3D modeling, integrated CAD/CAM systems available to shipbuilders .U.S. Navy has been at the forefront of Simulation Based Design .Robotics is next frontier although it may not be realised by U.S. shipyards because of their low throughput

COURSE NOTES: .Paper, "CAD/CAM Chapter from new SD&C Book," by J. Ross .PDF file: CADCAMCIM.pdf Shipyard Layout Shipbuilding practices and the layout of the shipyards have developed over a long period of time as both the ships being built and the production technology have changed. The shipyard layouts also had to suit the natural environments in which they were placed. Shipyards should be close to and have deep water access to the open sea, and land or sea access for delivery of equipment, components and raw material. Most shipyards are located on river banks or the shores of bays, protected from the open sea. The method of moving the ship from land to the water depended on tide and shipyard configuration. Drydocks (Graving Docks) were used for building ships as early as the 16th century in Venice and for the building of the Royal Navy's large ships of the line in the 18th century. Side launching of ships goes back to iniquity with two famous side launched ships being Cleopatra's Barge and Brunell's GREAT EASTERN. Nearer home, most of the Gulf coast shipyards use the side launch method. End launching is equally old and until the modern development of drydocks for shipbuilding, which started in the 1960's, was the most common approaches used by the world's shipbuilders. Launching by floating dock and ship elevators is a relatively recent (since 1970's) development. The natural land topography found along river banks influenced the shipyard layout. Where there were steep hills or rocky cliffs, shipyards were squeezed onto the banks or shore and stretched along them to provide the needed land area, as shown in Figure 1.1. It also developed as some shipyards grew to multiple berths, sometimes as many as 4 to 8. This layout is called by various names, such as wide and lateral. It is easy to see that material flow was not ideal, especially as shipbuilding adopted large block construction. Many of the U.S. World War II shipyards were of this type with over 20 slipways. A current example of this type is the Avondale shipyard in New Orleans, as shown in Figure 1.2, which has the additional problem of having to transport the structural blocks up to and over the Mississippi river levee. Over time other industries, and housing developed around these shipyards and as ships increased in size, the shipyards were constrained by their surroundings. Figure 1.3 is a current layout of the Mitsubishi Heavy Industries shipyard in Nagasaki, and it can be seen that they had to literally "move mountains" to develop it into a suitable facility to build modern ships. However, many shipbuilders found it necessary to develop entirely new shipbuilding facilities in the 1960's, including Mitsubishi and many others in Japan, Gothenburg Shipbuilding in Sweden, Odense Steel Shipyard in Denmark, and even Litton in the U.S. These shipyards tended to select their sites without natural constraints, so that the best shape could be used. The "new" shipyards were developed to best suit the planned building process and an alternative layout was developed. This was based on straight continuous flow of material and the two classic cases are the B&W shipyard in Copenhagen (Figure 1.4) and the Arendal Shipyard in Sweden (Figure 1.5). This layout is called deep, straight flow or narrow type. The B&W shipyard used part of its existing shipyard for the steel preparation and fabrication and was not a "true" straight line flow. However the Arendal shipyard was designed from the start as a continuous straight line flow layout, as shown in Figure 1.6. It also utilized the "ship extrusion" approach. It is sad to say that both shipyards are closed. Most other shipyards are variations of this type trying to seek a happy medium of shape to suit their location. Many Japanese shipyards are almost square as shown in Figures 1.7 and 1.8. Litton's shipyard in Pascagoula is also squarish in shape as shown in Figure 1.9, but uses a floating drydock for launching whereas most of the other examples used graving docks. In the mid-1970's the "ship factory" was developed by Appledore in Devon, England and later used to modernize two other larger shipyards in the same shipbuilding family in Sunderland, in the North East of England. The layouts for the ship factories are shown in Figures 1.10 and 1.11. The compactness as well as the covered building dock were hallmarks of this type. While Korea has continued to build new shipyards as well as expand the facilities of existing shipyards, the only other new shipyards are being built in China. Germany is completely renovating some of the existing East German shipyards while its West German shipyards are closing down. All existing shipyards have undertaken significant reorganization in order to stay in the highly competitive international shipbuilding market, which is driven by low prices due to over capacity. That is, there are too many shipbuilders chasing too few ship orders. The new and remodeled shipyards concentrate on installing new equipment that helps them improve in four areas of shipbuilding, namely:

o structural fabrication and assembly (steel shops), o pipe fabrication (pipe shop), o advanced outfitting (package unit shop), and o building berth

The improvements in steel shops include:

o both wet and dry plasma cutting and marking of plate parts, o automatic catridge stowage systems for structural profiles, o robot profile line, o one sided welding, o panel cutting (perimeter) and marking, o large and small panel lines with robot stiffener welding, robot welding for web frames, o pin jigs on movable platform to provide limited panel line flow to curved block construction, and o grand block construction.

Other non-equipment improvements that parallel the equipment improvements are weld through primer, immediate repair of process damaged primer by process worker and elimination of need to re-blast block before final block painting. Figures 1.12 through 1.15 show typical current steel shop layout and processing lines. There has been a general trend to move as much work as possible into the steel shops and minimizing time on the building berth. This requires larger covered areas for structural work. Another trend in European shipyards is to compact shops all connected together with minimum buffer space as shown in Figure 1.16, which is the remodeled shipyard in Wismar, Germany. In some ways this is similar to the Ship Factory concept developed by Appledore, and even the steel shop arrangement at Odense Steel Shipyard shown in Figure 1.17, even though the building dock is not adjacent to the shops. The enclosing of the building berth, slipway or dock, as shown in Figures 1.18 and 1.19, is the most recent trend, mostly in countries affected by significant bad weather, such as Northern Europe. Recent new Korean shipyards still follow the expansive layout where there are great spaces between the fabrication shop, the assembly shop and the building berth as shown in Figure 1.20, which is the Halla Shipyard. The paint sheds along the upper boundary are far removed from the steel shops and the building berth, requiring extensive travel by transporters. Pipe shops can be totally automated, although most shipyards seem to keep some manual work, to take care of unique or difficult pipe pieces. Robot pipe cutting, flanging, pultrusioning and bending are all required to achieve competitive productivity in moderate to high volume pipe fabrication. Figure 1.21 shows the layout of a shipyard automated pipe shop. Advanced outfitting is being used by most successful shipyards although there are a few that do not utilize it. Such shipyards usually utilize significant turn-key subcontracting (for all pipe, insulation, electrical, HVAC and coatings). It is easier to manage these sub-contractors if the ship is completed to a certain stage before the turn-key subcontractor starts his work rather than trying to integrate them with the shipyard's workforce and planning to accomplish advanced outfitting. When advanced outfitting is utilized the trend is for larger and more complete "grand units", often many levels high, such as the approach developed by Thyssen Shipyard in Germany and shown in Figure 1.22. There appears to be two trends in block sizes. First, where the building berth is integrated into the main buildings, the approach is to build blocks up to 250 tons. Second, when the building berth is remote from the shops, the approach is to build grand blocks from 700 to 1000 tons for crane lift and up to 3000 tons when positioned on the building berth by transporters (see Figure 1.23) and/or elevators (see Figure 1.24). These grand blocks are formed from smaller blocks of up to 200 tons. When the second approach is utilized, it must be decided whether to advance outfit the smaller blocks or wait until the grand block is constructed. Finally, most successful shipyards recognize that both steel and ship throughput are important criteria. To be internationally competitive, a shipyard requires a minimum of 60,000 tons of steel and 4 ships per year. Odense Steel Shipyard has 200,000 tons of steel throughput and up to 6 ships per year.