In general, the strength assessment for heavy lift vessel is carried out under two stages. The first stage is to comply with the requirement of KR (Korean Register of Shipping) Steel Barges and Rules for Classification of Steel Ships. At the second stage, the structural strength analysis by Finite Element Method is peformed. This paper describes the strength assessment considering various loads for the heavy lift vessel of sheerleg type.

While environmental concern is urging shipbuilding industry to reduce pollutant emission, it is necessary to design environmental friendly vessels. LNG as fuel for ship propulsion is proven to be effective way to reduce pollutant emission. In this study, we find optimum position of LNG fuel supply system on AHTS by considering vessel characteristic. Three different positions of fuel supply system are studied in this paper. Factors such as stability, strength and safety are examined in each position of fuel supply system.

Since CAD is advertised 1980s, all across industries have been changed through engineering, manufacturing and inspection. Also marine industry has adopted not only CAD but also various IT systems to make productivity higher. This paper includes research and development to improve traditional draft reading by using IT system, it has focused to build draft database for new vessels, to improve robustness measuring weather condition and to reduce accident possibility.

The juice carrier is the first ship built in korea. Special refrigerator system and cargo hold insulation with stainless steel tank were equipped on cargo hold. We studied optimum design of cargo hold insulation for reducing of ship building schedule and cost including good quality with refrigerating efficiency. From this study, general and newly specified juice carrier, technical method of cargo hold insulation system, air flow with division air wall, K-value calculation have been investigated.

Speed log measurement has always been of utmost importance to the mariners. To date the most accurate maritime speed measurement comes from Doppler measurement, where speed may be measured relative to either water(speed through water) or seabed(speed over ground). Recently, a clarification has been issued by the International Maritime Organization (IMO) regarding the speed measuring devices, which could ultimately impact the final arrangement of these devices for ships being constructed after July 1, 2014. This paper will discuss the clarification in depth and necessary action which shall be taken by the owners and operators of the ships impacted.

The design, procurement and fabrication of FPSO project ordered by Inpex Browse, Ltd. have been currently carried out by DSME(Daewoo Shipbuilding Marine and Engineering Co.). The unit will be installed and operated in the Ichthys field offshore of North-Western Australia and there are the particular design requirements to do with performance on the environment loads corresponding to max. 10,000 years return period wave. Also, the operational life of FPSO has to be over 40 years. With this background, this paper introduces the structural design procedure of crane pedestal foundation operated in north-western Australia offshore. The design of crane pedestal foundation structure is basically based on international design code (i.e. API Spec. 2C), Classification society's rule and project specifications. The design load cases are mainly divided into the crane normal operating conditions and crane stowed conditions according to environment conditions of the offshore with 1-year, 5-year, 10-year, 200-year and 10,000-year return period wave. This design experience for crane pedestal foundation operated in north-western Australia offshore will be useful to do engineering of other offshore crane structures.

In this study reviewed the validity of the estimated optimum trim by the numerical analysis. For this purpose, the numerical analysis of the trim optimization for 6500TEU container carrier and capesize bulk carrier were carried out using Star-CCM+, which results were compared with the results of model tests. The reliability of results of the numerical analysis was confirmed via comparing the resistance determined by the numerical analysis and model test. The performance of self-propulsion at each trim conditions were estimated using the calculated resistance by numerical analysis. The BHP at each trim condition were calculated by estimated performance of self-propulsion, which trend of results were confirmed similar trend of result of model test.

Common Structural Rules (CSR) about bulk carriers and double-hull oil tankers of International Association of Classification Societies (IACS) has been applied to ships contracted for construction since April 2006. By unifying each society's rules, the difference of opinion in the between shipyard and ship owners, classification was reduced, and CSR has been evaluated by rules the safety structure more enhanced. However, The CSR about the bulk carriers and double hull oil tankers, important design content standards, such as the local scantling calculation, static/dynamic load case and corrosion margin and etc., are different. Therefore in order to combine the CSR, the Harmonized CSR for bulk carriers and double hull oil tankers (H-CSR) was issued on 1, January, 2014, and will be apply to ships contracted for construction after 1st July 2015. It is necessary to verify the H-CSR to optimize the structural arrangement because effective date is not far off. In this study, we compared the impact by rule change for the hull girder shear strength of bulk carriers between CSR and H-CSR in respect of the yielding and buckling strength.

Application of newly conceptualized Anti-Splash Devices designed for COT vent pipes were studied on a P/V valve located on the upper deck of an oil carrier vessel. Anti-Splash devices are used in the shipbuilding industry in order to avoid oil overflow and spray accidents caused by excess pressure and vacuum condition in the cargo oil tanks. These conditions are caused by the transverse and longitudinal sloshing forces that arise from ship motion during sea voyages. The main issue with existing Anti-Splash device model is flux at the outlet of the Anti-Splash Device, and so, new conceptual models for the Anti-Splash device were developed and compared to existing Anti-Splash device model using CFD analysis. Transient analysis was used to capture the flow and velocity of each model and a comparative analysis was performed between old and new-concept models. This data was used to determine the optimal design parameters in order to develop an optimized Anti-Splash Device. A Factory acceptance test was performed on the new-concept models in order to verify the performance and efficiency against their design requirements and other criterion. The final step performed was to apply the optimized Anti-Splash Device models for COT vent pipes to an actual vessel and verify performance through a seawater cargo operation during a sea voyage as per the ship owner's request. The patent for the aforementioned device was obtained by the Korean Intellectual property Office dated Dec. 18th,2014.

In ship structure, many parts are in contact with inner or outer fluid as stern, ballast and oil tanks. Fatigue damages are sometimes observed in these tanks which seem to be caused by resonance with exciting force of engine and propeller. Vibration characteristics of these tanks in contact with fluid are significantly affected by fluid coupling effect. Therefore it is important to exactly predict vibration characteristics of tank structure. In order to estimate the vibration characteristics, the fluid-structure interaction(FSI) problem should be solved precisely. But it is difficult to estimate exactly the magnitude of the fluid coupling effect because it has some problems such as a fluid-structure interaction, influence by the free surface, vibration modes of structural panels and depth of water. In this paper, with fluid coupling effect, the effect of structural constraint between panels on the vibration characteristics are investigated numerically and discussed.

This paper presents fatigue analysis of helideck structures located in FPSO. After FPSO is moved to the target position where production of resource is performed, FPSO stays at the target position and performs production of resource, storage and off-loading during the design life. Helideck structure is located in FPSO essentially for the movement of personnel and life rescue at emergency situations by using helicopters. Because inertial load induced by FPSO motion and landing and taking-off load of helicopter occur at helideck structures cyclically, helideck structures should be designed to withstand fatigue loads. Therefore, The fatigue assessment of helideck structures should be performed with fatigue loads. Effect of stress concentration due to misalignment between welded plates is considered in fatigue assessment additionally.

An evaluation of the accidental limit state (ALS) for design of a semi-submersible drilling rig is one of the essential design requirements as well as ultimate limit state (ULS) and fatigue limit state (FLS). This paper describes the ALS evaluation on the explosion accident at shale shaker room of semi-submersible drilling rig. There are three steps for the ALS evaluation such as structural analysis at concept design, risk based safety design and structural analysis at detailed design. For the ALS evaluation at concept design, conceptual explosion overpressure from the Rule guided by the classification society was used in the structural analysis that was carried out using LS-DYNA. To set up the design accidental load (DAL), explosion analysis was carried out using FLACS taking safety barriers into consideration. Then, the structural analysis was carried out applying DAL for the ALS evaluation at detailed design. Through the ALS evaluation on the explosion at shale shaker room, the importance of the risk based safety design was described.

When floating platform or drilling unit is located at operating station during its design life, it has to have the sufficient stability considering external environment. To evaluate whether offshore structure is complied with the required design criteria for intact stability, the factors which decrease the righting moment have to be considered. Wind heeling moment is one of main factors because the direction is opposite to the righting moment. According to 2009 MODU CODE (Code for the construction and equipment of Mobile Offshore Drilling Units, 2009), wind heeling moment derived from wind tunnel test on scale model of offshore structure enables to apply as alternative given formula and method in 2009 MODU CODE. However, there is no the specific method for applying data derived from wind tunnel test. Based on the following reasons, this paper presents that the calculation method of wind heeling moment utilizing non-dimensional coefficient relative to wind loads (wind forces and moments) and the comparison with each method applying an example.

A BC-B type bulk carrier is rarely built, so the structural characteristics is not reported and familiar so far. The biggest difference between BC-B and BC-A type vessel is applying alternate cargo loading, which density is over $1.0ton/m^3$. In this paper, 150K DWT class BC-B type bulk carrier is calculated and compared with BC-A type vessel, which has same condition such as main dimension and deadweight, about prescriptive rule and FEA based on CSR. And aspect ratio of target vessel is smaller than typical capsize bulk carrier, so 150K and 180K bulk carrier, which applied BC-A type, are also compared to find feature of wide beam vessel.

In general, when ships are designed, structural strength and fatigue strength must be verified based on the relative rules respectively. In case of Slurry Iron Sand Carrier designed to carry Iron-Sand saturated at water content, there is no special consideration of fatigue strength analysis. However, this vessel is similar to Ore Carrier in consideration of the overall characteristics of loaded cargo and the shape of cargo hold. Therefore we verified fatigue strength based on fatigue analysis procedure of ore carrier in DNV Rules and carried out the study for improving of fatigue strength of Slurry Iron Sand Carrier.

In case of crude oil tanker, loading condition must be satisfied MARPOL damage stability criteria (Reg.28). But some specific demands are hard to content the criteria. So, it takes a lot of time and efforts to make loading condition reflecting these demands. In this study, PSO (Particle Swarm Optimization) is used to make loading condition to be satisfied the criteria. Study result is applied 'CROSSWAY (160,000 DWT Crude Oil Tanker)' in NAPA. The result shows that satisfy the criteria and other constraints and limitation.

Norwegian Continental Shelf(NCS) is known as rich oil & gas reservoir and takes one third(1/3) of total continental shelf of Europe.(As of year 2013, Norway ranked third in the world in terms of exporting natural gas.) Until recent low oil price stream, development of oil & gas in NCS was active and perceived as profitable business. This paper describes study of living quarter fire protection for PSA AoC to prepare for likely increasing demands of offshore projects in NCS field.