Cargo Tanks Research Articles

Improving the quality of produced water discharged in open waters by incorporating a microbiological treatment on operating offshore platforms

Produced water is the water that comes along with oil during the reservoir extraction and is the main subproduct of the petroleum industry, accounting for 3 to 5 times the global production of oil. The produced water separated from the oil still contains some oily fractions in its composition, making it necessary for some treatment before its discard (most common practice adopted on offshore platforms) or reuse. The traditional method of treatment is based on the physical separation of oil and water, driven by their density difference. This type of treatment is unable to remove dissolved or small diameter particles dispersed, which turned out to be an issue in face of some new legislation worldwide that lowered the maximum amount of total oil and grease (TOG) the water can have for its discharge. Biological treatment is a widespread method for treating wastewater in several different industries due to its relative simplicity and low operational costs. Nevertheless, as it is a treatment that normally requires large-volume vessels, it is not used on offshore platforms due to a lack of space for such high dimension equipment. The objective of this research was to carry out a literature review using the article and patent search bases to find technical options that allow the use of biological treatment for water produced on offshore oil production platforms. Next, propose a model to incorporate biological treatment and estimate the performance of this produced water treatment model. An arrangement was proposed to convert a cargo tank of an operating offshore oil platform into a microbiological reactor. The conversion could be useful to treat the produced water that has a concentration of oil above the maximum limit allowed to discharge or to promote the additional extraction of a fraction of oil that could not be removed by the conventional treatment plants. The objective of this research was to perform a literature review to find technical options that could allow the use of biological treatment for the produced water in offshore oil-producing platforms, to propose a model to incorporate the biological treatment, and to estimate the performance of this model treating produced water. After researching articles and patents in the literature, it was seen that the Upflow Anaerobic Sludge Blanket (UASB) was the best type of reactor to be incorporated into an offshore platform. The reactor was chosen since it had good performance in treating produced water anaerobically and low sludge production. The UASB reactor most resembled the arrangement of a cargo tank, which was a paramount factor for the feasibility of the process's success. It is expected that the cargo tank converted to an UASB could remove at least an extra 30% of the total oil and grease (TOG) when compared to the traditional physical removal process existent for the produced water. However, it is still necessary to perform some laboratory tests to better predict the removal rate that would be observed in using this microbiological treatment with the high salinity-produced water from pre-salt Brazilian fields.

Kinerja Inert Gas Generator Untuk Mendapatkan Oksigen Konten 3% Pada Gas Lembam

Inert Gas System is a machine that functions as a security system to prevent explosions on tankers. Explosion prevention is carried out by introducing inert gas into the cargo tank with the aim of reducing oxygen levels in the cargo tank atmosphere so as to prevent the formation of a flammable gas mixture. Inert gas contains very little oxygen, namely 1-2% by volume. The device that produces the inert gas is called the Inert Gas Generator (IGG). The purpose of this study was to determine the factors that cause high oxygen content contained in the inert gas and the efforts made related to the factors mentioned so that the inert gas generator can work optimally. The research method used by the author is descriptive qualitative with Fishbone data analysis techniques and SWOT analysis. The results of the study stated that the factors causing oxygen content of more than 3% were dirty fuel filter, too much combustion air supply, oxygen analyzer that was rarely calibrated, flow sampling was too large, fuel quality was not good, lack of crew knowledge. to PMS (Plan Maintenance System) IGG. Efforts have been made to clean the fuel pump filter, close the air capacity valve a little, calibrate the oxygen analyzer according to the PMS schedule, reduce the sampling valve flow into the oxygen analyzer, add fuel oil treatment (additives) to the fuel, pay attention to the IGG maintenance schedule according to PMS, restore the maintenance implementation system based on the PMS inert gas generator schedule.

Biological regulation on synovial fibroblast and the treatment of rheumatoid arthritis by nobiletin-loaded tetrahedral framework nucleic acids cargo tank

The hyperplasia and destruction of synovial tissue have an important impact on the development of rheumatoid arthritis (RA), the abnormal proliferation and migration of synovial fibroblast in synovial tissue is similar to tumor cells. Targeting anomalous synovial fibroblast and designing a high bioavailability nano drug delivery system can reduce the dosage for the treatment of rheumatoid arthritis and it is of great significance to reduce toxic and side effects and improve curative effect. In this experiment, the nobiletin-loaded tetrahedral framework nucleic acids cargo tank was established, carrying anti-inflammatory small molecule monomer drug nobiletin with minimal bioavailability. Both in vitro cell experiments and in vivo animal studies proved the nano cargo tank enhance the role of nobiletin in reducing the invasiveness of pathological synovial fibroblast and promote their apoptosis, effectively alleviate the disease development of rheumatoid arthritis.

Equivalent linear roll damping of a FPSO coupled with liquid sloshing in a pair of two-row tanks

The increased risk of reduced transverse stability by free surfaces in cargo tanks in floating vessels such as Floating Production Storage and Offloading (FPSO) units, is well known. Roll decay testing remains the most common method for determining roll damping characteristics. Few works evaluating roll characteristics coupled with the effect of liquid motion exist. In this paper, a series of roll decay tests are carried out for a FPSO model with a pair of two-row prismatic tanks. The four compartment tanks are filled to different levels, and the equivalent linear damping is obtained using the Quasilinear (Logarithmic Decrement) method and the Froude Energy method. The effect of draft change for each loading condition is analyzed based on the average equivalent linear damping coefficient and the effect of the liquid cargo sloshing is also discussed. The results show that an increase in liquid cargo, the location of cargo load, and the geometry of the cargo tank affect the damping of the vessel.

Weight distribution algorithm for global ship analysis in preliminary design stage

Abstract Structural analysis, based on a global ship model, is vital for examining the structural strength and safety of a hull. In the “NASTRAN” global ship model, only the structural members and cargo tank of a ship are modeled and the outfit, electric system, and other tanks and liquid are omitted from the model. The additional weight of these omitted elements, however, constitutes part of the light weight of the ship and must be considered in conducting an accurate structural analysis of the ship. Generally, the weight of these omitted elements is calculated using the trim and stability information of the ship and is then added to the model. In such cases, the center of gravity of the global ship model, which now includes the weight of these omitted elements, must be adjusted to the target center of gravity required for the analysis. In this study, an algorithm was developed to satisfy the target center of gravity while distributing the weight of these omitted elements to the global ship model using Gaussian elimination. The algorithm was developed using C#, and its accuracy was verified by applying it to the global ship models.

Reduced energy losses during transportation of drilling fluid by Platform Supply Vessels

The object of research is the process of drilling fluid transportation by Platform Supply Vessels. The subject of research is the energy losses when pumping drilling fluid from a platform supply vessel to an oil platform. The research was carried out on a vessel with deadweight of 3840 tons. It has been experimentally established that for a drilling fluid with an initial density of 1272 kg/m3 for transportation within 6–48 hours, the following changes in rheological characteristics occur: – a layer with a density of 1235–962 kg/m3 is formed on the surface of the cargo tank; – a layer with a density of 1283–1422 kg/m3 is formed in the bottom part of the tank; – sedimentation resistance decreases by 3.89–47.82 %. A variant of modernization of the drilling fluid transportation system by installing additional circulation pumps providing forced circulation of the drilling fluid between cargo tanks is proposed. Additional circulation of the drilling fluid with an initial density of 1272 kg/m3 for transportation within 6–48 hours ensures that the rheological characteristics are maintained in the following range: – density on the surface of the cargo tank 1270–1232 kg/m3; – density in the bottom of the tank 1288–1338 kg/m3; – decrease in sedimentation resistance 1.42–7.92 %. Similar results were established for drilling fluid with an initial density of 1323 kg/m3 and 1188 kg/m3. To reduce energy losses, the process of unloading the fluid onto the oil platform is proposed to be performed at the completion of the technological process of unloading the vessel. At the same time, due to a decrease in draft and an increase in the height of the freeboard of the vessel, the static component of the pressure and hydraulic losses of the cargo pump decrease. A set of studies for drilling fluids with different initial density (1272 kg/m3, 1188 kg/m3, 1323 kg/m3) confirmed that when using additional X-shaped drilling fluid circulation: – relative performance of cargo pumps increases from 37–57 % to 88–96 %; – the time of pumping the drilling fluid from the vessel to the oil platform is reduced from 7.1–8.5 to 3.3–3.8 hours. The presented results confirm the expediency of using additional X-shaped circulation of the drilling fluid to reduce energy losses during transportation by Platform Supply Vessels.

A novel design approach for estimation of extreme responses of a subsea shuttle tanker hovering in ocean current considering aft thruster failure

The subsea shuttle tanker (SST) is an innovative 33 600-ton underwater cargo tanker designed to transport CO2 to marginal fields. During offloading, the SST will approach and hover in the vicinity of the subsea well. A remotely operated vehicle (ROV) will carry and connect a flexible flowline from the subsea well to the SST. CO2 is then offloaded via this flexible flowline. The offloading process takes four hours. During this time, the SST is subjected to time-varying current load effects, and it will dynamically keep its position using its ballast tanks, propeller, and thrusters. Knowing the extreme positional responses is essential. The extreme heave motion determines the maximum depth and corresponding the maximum hydrostatic loading; hydrostatic loading is a dominating load and drives the collapse design of the SST hull. Further, the extreme surge motion determines the flowline length required to avoid snap loads. In this paper, the extreme positional responses of the SST when the aft thruster fails during offloading is investigated for mean current velocities of 0.5 and 1.0 m/s using the averaged conditional exceedance rate (ACER) method. The empirical data is generated using time-domain simulations with a 2D planar Simulink model. The proposed methodology provides an accurate bivariate extreme value prediction, utilizing all available data efficiently. In this study, the estimated vessel response 5 years return level values and contours, obtained by ACER 1D and 2D methods. It is shown that the extreme responses with return periods of 5 years are, in general, higher than the maxima of the 4 h response by a factor of two. Further, it is seen that the response at the aft where the thruster fails is 1.3–2.6 times larger than the response at the fore of the SST. Based on the overall performance of the proposed method, it was concluded that the ACER 1D and 2D methods could provide robust and accurate both univariate and bivariate predictions based on accurate dynamic vessel motion numerical simulations.

Creation of an innovative robot with a gripper for moving plant microshoots from the in vitro transport tank to the working tank with soil ground at the stage of their adaptation in soil ground during microclonal reproduction

The industrial development of cities is the main cause of the destruction and degradation of natural resources around the world. Urbanization negatively affects the species composition of plants, the atmosphere and soil cover of areas of populated areas of large cities of the World. Tree plantations are the main mechanism for stabilizing the ecological situation in large cities and arid territories of the countries of the World. In this regard, in order to obtain a large number of genetically identical plants using their micropropagation, it is necessary to automate the main stages of this technological process. The result of the study is the creation of an adaptive phalanx gripper of a robotic complex for automating the technological process of handling operations. That will have a positive effect on solving the urgent problem of planting greenery in large cities and areas of arid territories not only in the Republic of Kazakhstan, but also in other countries of the World and represents a fundamentally new approach to solving the environmental problems of the Earth. The article substantiates various options for structural-kinematic schemes of the robot gripper, taking into account the stochastic conditions of its interaction with the overloaded object. Mathematical methods have been created for the selection and justification of the geometric, structural-kinematic and dynamic parameters of grippers for overloading plant microshoots and their computer 3D models. Software has been developed for modeling the functioning of a remotely controlled physical prototype of a mobile robot with an adaptive gripper for reloading microshoots from a transport tank to a cargo tank.

Control and regulation of the density of technical fluids during their transportation by sea specialized vessels

The object of research is the process of transporting drilling slurry through specialized marine vessels of the Platform Supply Vessels class. The subject of research is the sedimentation stability of the drilling slurry along the height of the cargo tank, which is proposed to be defined as a relative change in vertical density near the surface and bottom of the cargo tank. The studies were carried out on a specialized sea vessel with a displacement of 7320 tons. The design of the vessel provided for the reception and transportation of drilling slurry in four cargo tanks located on the port and starboard sides of the vessel. It has been experimentally established that during the 48-hour transportation, the density of the drilling slurry in the bottom part increases to 19.7 %; decrease in density on the surface – up to 7.8 %; decrease in the sedimentation resistance of the drilling slurry along the depth of the cargo tank – up to 29.85 %. A variant of modernization of the drilling slurry transportation system by installing additional circulation pumps providing forced circulation of the drilling slurry between cargo tanks is proposed. By using programmable microcontrollers (performing turning on/off the circulation pumps), it is possible to provide the following conditions for transporting the drilling fluid: an increase in the density of the drilling fluid in the bottom part up to 0.3 %; decrease in density on the surface – up to 0.25 %; decrease in the sedimentation resistance of the drilling slurry along the depth of the cargo tank – up to 8.01 %. It has been experimentally established that the creation of additional circulation and automatic support of the sedimentation resistance of the drilling fluid in the range of 2–7 % contributes to: – increasing the relative performance of cargo pumps from 38–55 % to 92–96 %; – reducing the time of pumping drilling slurry from cargo tanks to the drilling platform from 7.1 to 3.2 hours; – maintaining the technical condition of equipment, pipelines and elements of the drilling slurry transportation and pumping system.

PRESSURE-IMPULSE DIAGRAM OF THE FLNG TANKS UNDER SLOSHING LOADS

Sloshing impact loads can cause severe structural damage to cargo tanks in liquefied natural gas floating production storage offloading units (LNG-FPSOs or FLNGs). Studies of sloshing can be classified into two types, namely, hydrodynamics-related and structural mechanics-related studies. This study is a sequel to the authors’ previous studies (Paik et al. 2015; Lee et al. 2015), but is more related to issues of structural mechanics. In this study, a new method for probabilistic sloshing assessment, which has been previously developed by the authors, is briefly explained. The nonlinear impact structural response characteristics under sloshing impact loads are examined by a nonlinear finite element ANSYS/LS-DYNA method. An iso-damage curve, representing a pressure-impulse diagram, is derived for the self-supporting prismatic-shape IMO B type LNG cargo containment system of a hypothetical FLNG. The insights developed from this work can be useful for the damage-tolerant design of cargo tanks in FLNGs.

RELIABILITY OF DETERIORATED MARINE STRUCTURES BASED ON MEASURED DATA

Reliability assessment of a corroded deck of a tanker ship subjected to non-linear general corrosion wastage is performed, accounting for an initial period without corrosion due to the presence of a corrosion protection system, and a non-linear increase in wastage up to a steady state value. The reliability model is based on the analysis of corrosion depth data. Two types of uncertainties are accounted for. The first one is related to the corrosion degradation trend as a function of time, which is identified by a sequence independent data analysis. The second uncertainty is related to the variation of the corrosion degradation around its trend, which is identified as a stochastic process, and is defined based on the time series analysis. The time series determines the autocorrelation and spectral density functions of the stochastic process applying the Fast Fourier transform. The reliability estimates with respect to a corroded deck of cargo tank of a tanker ship is analysed by a time variant formulation and the effect of inspections is also incorporated employing the Bayesian updating formulation.

Numerical approach to analyze fluid flow in a type C tank for liquefied hydrogen carrier (part 1: Sloshing flow)

The demand for clean energy use has been increasing worldwide, and hydrogen has attracted attention as an alternative energy source. The efficient transport of hydrogen must be established such that hydrogen may be used as an energy source. In this study, we considered the influences of various parameters in the transportation of liquefied hydrogen using type C tanks in shipping vessels. The sloshing and thermal flows were considered in the transportation of liquefied hydrogen, which exists as a cryogenic liquid at −253 °C. In this study, the sloshing flow was analyzed using a numerical approach. A multiphase sloshing simulation was performed using the volume of fluid method for the observation and analysis of the internal flow. First, a sloshing experiment according to the gas-liquid density ratio performed by other researchers was utilized to verify the simulation technique and investigate the characteristics of liquefied hydrogen. Based on the results of this experiment, a sloshing simulation was then performed for a type C cargo tank for liquefied hydrogen carriers under three different filling level conditions. The sloshing impact pressure inside of the tank was measured via simulation and subjected to statistical analysis. In addition, the influence of sloshing flow on the appendages installed inside of the type C tank (stiffened ring and swash bulkhead) was quantitatively evaluated. In particular, the influence of the sloshing flow inside of the type C tank on the appendages can be utilized as an important indicator at the design stage. Furthermore, if such sloshing impact forces are repeatedly experienced over an extended period of time under cryogenic conditions, the behavior of the tank and appendages must be analyzed in terms of fatigue and brittle failure to ensure the safety of the transportation operation.

Economic Evaluation of an Ammonia-Fueled Ammonia Carrier Depending on Methods of Ammonia Fuel Storage

This study proposed two concepts for ammonia fuel storage for an ammonia-fueled ammonia carrier and evaluated these concepts in terms of economics. The first concept was to use ammonia in the cargo tank as fuel and the second concept was to install an additional independent fuel tank in the vessel. When more fuel tanks were installed, there was no cargo loss. However, there were extra costs for fuel tanks. The target ship was an 84,000 m3 ammonia carrier (very large gas carrier, VLGC). It traveled from Kuwait to South Korea. The capacity of fuel tanks was 4170 m3, which is the required amount for the round trip. This study conducted an economic evaluation to compare the two proposed concepts. Profits were estimated based on sales and life cycle cost (LCC). Results showed that sales were USD 1223 million for the first concept and USD 1287 million for the second concept. Profits for the first and second concepts were USD 684.3 million and USD 739.5 million, respectively. The second concept showed a USD 53.1 million higher profit than the first concept. This means that the second concept, which installed additional independent fuel tanks was better than the first concept in terms of economics. Sensitivity analysis was performed to investigate the influence of given parameters on the results. When the ammonia fuel price was changed by ±25%, there was a 15% change in the profits and if the ammonia (transport) fee was changed by ±25%, there was a 45% change in the profits. The ammonia fuel price and ammonia (cargo) transport fee had a substantial influence on the business of ammonia carriers.

Numerical Study of the Action of Convection on the Volume and Length of the Flammable Zone Formed by Hydrogen Emissions from the Vent Masts Installed on an International Ship

International ships carrying liquefied fuel are strongly recommended to install vent masts to control the pressure of cargo tanks in the event of an emergency. However, the gas emitted from a vent mast may be hazardous for the crew of the ship. In the present study, the volume and length of the flammable zone (FZ) created by the emitted gas above the ship was examined. Various scenarios comprising four parameters, namely, relative wind speed, arrangement of vent masts, combination of emissions among four vent masts, and direction of emission from the vent-mast outlet were considered. The results showed that the convection acts on the volume and length of an FZ. The volume of an FZ increases when there is a reduction in convection reaching the FZ and when strong convection brings hydrogen from a nearby FZ. The length of the FZ is also related to convection. An FZ is elongated if the center of a vortex is located inside the FZ, because this vortex traps hydrogen inside the FZ. The length of an FZ decreases if the center of the vortex is located outside the FZ, as such a vortex brings more fresh air into the FZ.

Регулирование плотности бурильной суспензии при её транспортировке судами класса Platform Supply Vessels

Annotation – The issues of maintaining the drilling fluid density during its transportation from shore to the oil drilling platform by the Platform Supply Vessels were considered. The research was carried out on the vessel of 5650 deadweight tons, which made 2 ... 2.5 day voyages from port to drilling platform with possible waiting for direct approach to the platform for 1 ... 1.5 days. The drilling fluid was transported in four tanks of equal-size, arranged in pairs on each side of the vessel. It was found that during this period of time there is a latent stratification of drilling fluid along the depth of cargo tank, causing stratification of its density. The density of the drilling fluid was measured at depths corresponding to 10, 50 and 90 % of the total tank depth. The drilling fluid density stratification is defined as the relative density change in the upper (at 10 % depth) and lower (at 90 % depth) parts of the cargo tank. The hydrometer was used to measure density, allowing measurements in the range of 650 ... 1630 kg/m3 with an accuracy of 1 kg/m3 while controlling the temperature. Density measurements were taken at 6-hour intervals. It has been experimentally proved that during the 48-hour transportation of the drilling fluid with the density of 1295 kg/m3, the density value at the indicated depths is 1163 and 1524 kg/m3 respectively, while the density stratification reaches 31 %. It is offered to prevent the density stratification by creating a forced X-shaped circulation of the drilling fluid between cargo tanks which stand side by side. It is offered to regulate and maintain automatically the drilling fluid density in the range of 2 ... 7 % by using programmable controllers. When the density stratification reaches 7 %, the controller switches on the circulation pumps and circulates the drilling fluid between tanks which stand side by side. This increases the drilling fluid uniformity and helps to reduce the density stratification along the depth of the cargo tank. The process of additional circulation of the drilling fluid is rationally ensured until the density stratification reaches a value of 2 %. Fulfilment of the above-mentioned conditions will ensure that the drilling fluid maintains its operational properties and the energy consumption associated with the additional operation of the circulation pumps is minimised.

Quantitative failure analysis for static electricity-related explosion and fire accidents on tanker vessels under fuzzy bow-tie CREAM approach

Cargo operations on tanker vessels involve high risks to crew and the marine environment. At the time of loading and unloading of cargoes and tank cleaning operations, consequences of accidents may be severe such as loss of lives, property loss and marine pollution. One of the most critical accidents is an explosion which may advance to a large fire. An explosion may occur due to flammable and combustible materials, electric arcs, dangerous operations, like hot work on deck, or static electricity. This study focuses on the issue of static electricity, which is one of the serious threats onboard and can cause large explosions under hazardous conditions if a discharge is in contact with nearby flammable gases or air mixture. In a bow-tie structure, static electricity-related explosion and fire accident was determined as the top event. In the fault tree diagram, intermediate events were considered as the flammable atmosphere in a tank, operational failures, technical failures, and unsafe practices which cover direct human errors. Fuzzy logic and Cognitive Reliability and Error Analysis Method (CREAM) were used for quantitative failure analysis, and the probability of accident risk was found as 6.31E-02. Findings show that the most critical contributions to the top event are minimal cut sets of lack of monitoring cargo tank atmosphere, inadequate actions for reducing the O2 level in tank, failure to understand safety data sheets, failure to follow procedures, non-bonded ullage & sample apparatus. The research provides a significant contribution to the literature and gives information regarding static electricity risks to ship officers, tanker safety superintendents and other maritime authorities to improve the safety of cargo operations.

Burst pressure design of the cargo tank used in a novel large subsea freight-glider

This paper presents the burst pressure design of the cargo tank used in the University of Stavanger (UiS) Subsea Freight-Glider (USFG). The USFG is an innovative large underwater cargo glider drone that is 50 m long and has a DWT of 1500 ton. It uses variable-buoyancy propulsion instead of traditional propellers for movement. This is an extremely efficient propulsion method and allows the USFG to achieve an average energy consumption of less than 10 kW. Structural weight is a premium as the USFG is required to be neutrally buoyant in water. Therefore, the design of the cargo tank which is the largest component in the USFG needs to be optimal for minimal structural weight. One approach used in design optimisation is to utilise design codes and/or methods that are more precise and therefore allow for lower safety margins. This approach will be investigated in this paper for the burst pressure design of the cargo tank. The different parts of ASME BPVC codes will be compared. The sensitivity of the codes to changes in design parameters is also investigated. Lastly, some comments on the use of reliability methods to further optimise the design are also presented.

Indoor accelerated controlled corrosion degradation test of small- and large-scale specimens

The work presented here is a part of a long-term project analysing the structural behaviour of ageing marine structures. An accelerated corrosion degradation set-up was developed to reproduce corroded marine structural specimens of different degrees of degradation, controlling various natural factors, i.e., temperature, oxygen content, salinity, and flow velocity. The nine stiffened plates of 1.2 m length and 30 small scale specimens made of mild steel of three different thicknesses have been corroded. The mean corrosion depth and rate have been controlled during the degradation process for all specimens. The corrosion degradation characteristics have been measured and analysed. In the case of small-scale specimens, microscope scanning, and for the stiffened plates, ultrasonic thickness measurements were performed. The obtained corrosion surfaces are highly non-uniform. During the corrosion degradation, a number of measurements were performed to satisfy a confidence level of 95% and an error of 10%. The developed corrosion degradation is compared with a real corrosion depth measurement of ship deck plates of ballast and cargo tanks, showing a very good similarity in the trend and the corrosion acceleration, concluding that the developed corrosion degradation controlled experimental set-up is efficient in reproducing marine structural specimens of different degree of degradation for further mechanical testing.

Evaluation of the ventilation system in an LNG cargo tank construction platform (CTCP) by the AHP-entropy weight method

Evaluation of the ventilation system in an LNG cargo tank construction platform (CTCP) by the AHP-entropy weight method

Data transformation technology of 3D ship structure model for approval

Objectives Chinese ship design and approval institutions usually use different 3D design platforms, which can cause the problems of unsmooth model transfer and ineffective data conversion. This paper addresses the data conversion techniques of 3D ship structure models to ascertain whether a converted model can be directly used by classification societies for approval. Methods By analyzing the model data of the CAD and CAE systems, the required data for generating an approval-oriented 3D hull structure model is summarized. The storage format of the required data and the interface between the stored data and common 3D software platforms are introduced. Taking a cargo tank section of a ship as an example, the required data of the 3D model of the target section is stored in an XML data file. Based on this data file, the design model and FE analysis model of the target section are reconstructed through CATIA and Patran software, and equipped with a secondary developed interface. Results The reconstructed model has been submitted to Bureau Veritas (BV) for direct approval of the structural design. Conclusions The data conversion method proposed in this paper simplifies model transfer among different platforms, and can provide valuable references for realizing the paper-free approval of 3D ship models.