Table of Content

    25 August 2018, Volume 5 Issue 4 Previous Issue    Next Issue
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    Development Status and Prospects of Remotely Operated Vehicles
    LIAN Lian, WEI Zhao-yu, TAO Jun, REN Ping, MA Xia-fei
    2018, 5 (4):  223-231.  DOI: 10.12087/oeet.2095-7297.2018.04.01
    Abstract ( 567 )   PDF (3209KB) ( 225 )  
    Human beings cannot explore and exploit the deep ocean resources without the help of submersibles. Among all kinds of submersibles, the remotely operated vehicles (ROVs) have been widely deployed since they have strong working ability and are free from power constraints. In this work, we first present and summarize the definition, basic classification, system composition, developing history and status, application demanding and national strategic importance for the ROVs. Then, some key technologies for the current design and development of ROVs are presented and discussed. Finally, some possible developing directions and the characteristics of the future ROVs are summarized, which can be referenced to develop and design the new generation ROVs.
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    Design and Analysis for the Butt Locking Mechanism of ROV Tool Library
    WU Yu, JIAO Hui-feng, ZHANG Kang, LI Xiao-xiao, ZHANG Lin-dan
    2018, 5 (4):  232-236.  DOI: 10.12087/oeet.2095-7297.2018.04.02
    Abstract ( 319 )   PDF (4114KB) ( 84 )  
    The operating efficiency of remotely operated vehicle (ROV) could be improved by replacing its tool library quickly.The butt locking mechanism of ROV tool library is the key device for the replacing operation.We design such a butt locking mechanism according to the ISO 13628-8 (2002) standard. The principle of cylinder locking mechanism is introduced, as well as the locking force calculation formulas.Meanwhile, the hydraulic force is reduced through optimizing the structural parameters of the locking finger.
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    Application of Virtual Instrument Technology in Insulation Detection of Manned Submersible
    QI Hai-bin, DING Zhong-jun, ZHANG Yi, YANG Yi-fan, LIU Xiao-hui
    2018, 5 (4):  237-241.  DOI: 10.12087/oeet.2095-7297.2018.04.03
    Abstract ( 266 )   PDF (3763KB) ( 74 )  
    The insulation fault of “JIAOLONG” manned submersible during its experimental application stage is introduced. Based on the insulation detection equipment of “JIAOLONG” manned submersible, we develop an insulation fault detection system using MCGS embedded virtual instrument technology to acquire the grounding detection data and deal with them in real time, which greatly improves the accuracy and efficiency of the insulation detection and provides the most effective assistant for the pilot to detect and find the underwater ground fault in real time. With good application prospect and development potential, this technology can be widely used in the field of insulation grounding detection of underwater vehicles.
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    Case Study and Enlightenment of the Development of Stones Deepwater Offshore Oilfield
    DU Qing-gui, TAN Guo-rong, LIU Cong, ZHANG Peng, FU Dong-ming
    2018, 5 (4):  242-247.  DOI: 10.12087/oeet.2095-7297.2018.04.04
    Abstract ( 292 )   PDF (2220KB) ( 84 )  
    The Stones Oilfield is the deepest offshore oilfield developed independently in the world. The deep high-pressure high-temperature (HPHT) reservoirs with low permeability bring unprecedented challenges to the development. The Stones Oilfield is introduced in detail, including the location, reservoir characteristics and project schedule. The main production facilities are summarized, and the project experience and results are analyzed. The research results may provide reference for the development of deepwater oil and gas fields.
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    Localization Prototype Design of Dual-Fuel Direct-Fired Inert Gas Generator for FPSO
    SUN Jing, WANG Chun-sheng, SHANG Chao, ZHENG Xiao-peng
    2018, 5 (4):  248-251.  DOI: 10.12087/oeet.2095-7297.2018.04.05
    Abstract ( 282 )   PDF (1920KB) ( 44 )  
    Inert gas system can provide safe and stable oil storage environment for the cargo oil tank of floating production, storage and offloading unit (FPSO). The localization of inert gas equipment has great significance for breaking the overseas technical monopoly and reduce oilfield development investment.We introduce the structural design, numerical simulation and key technologies of dual-fuel inert gas generator localization and list the successful practice of the equipment prototype, which was jointly developed by CNOOC and equipment manufacturer. The manufacturing of this prototype is a big promotion for the localization of inert gas generator.
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    Fatigue Analysis of Truss Tubular Joints of a New-Type Production and Storage SPAR
    MA Wang-kou, LIU Jun
    2018, 5 (4):  252-258.  DOI: 10.12087/oeet.2095-7297.2018.04.06
    Abstract ( 407 )   PDF (1150KB) ( 66 )  
    Spectral fatigue analysis method for truss tubular joints is studied and used to analyze the truss tubular joints of a new-type production and storage SPAR based on the sea condition of South China Sea. The results show that the fatigue strength of truss tubular joints of the new-type SPAR satisfies design requirement, and the fatigue strength of columns is worse than that of braces. Contributions to fatigue damage by axial force,in-plane bending moment and out-of-plane bending moment of braces are analyzed individually as well. The results show that the fatigue damage at diagonal braces is mainly caused by axial force of braces,the fatigue damage at horizontal braces is mainly caused by in-plane bending moment,while out-of-plane bending moment has little effect on fatigue damage at all braces.
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    Calculation of Horizontal Wave Impact Loads and Its Application to Local Structure Design of Column Stabilized Units
    WU Xin-yi, CUI Jin, NIE Yan, HUO Fa-li, WANG Ning
    2018, 5 (4):  259-265.  DOI: 10.12087/oeet.2095-7297.2018.04.07
    Abstract ( 330 )   PDF (9032KB) ( 38 )  
    When the air gap of the column stabilized units turns out to be negative, the evaluation for the consequences of the negative air gap is needed, which includes the calculation of horizontal wave impact loads. According to the method of engineering design and the related international codes, a practical method is proposed for the engineering design of the column stabilized units. As a demonstration, the forward bulkhead of a certain column stabilized unit is analyzed. The wave impact loads on the local structure is calculated and the transient simulation is performed by means of the finite element method (FEM). Finally, the strain and deformation in the forward bulkhead under the horizontal wave impact loads are obtained. The results show that the effect of horizontal wave impact loads on the vertical surface of deck box cannot be ignored. Thus, once the air gap of the column stabilized units is negative, the horizontal wave impact loads on the vertical surface of deck box must be fully considered. The local structure should be reinforced and re-analyzed based on the simulation results until the design meets the rules and standards.
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    SCR Strength Study for the Application of SCR to Semi-Submersible Platform in the South China Sea
    ZHANG Xue-hui, XU Ai-jin, CHENG Yong-ming, ZHANG Wei, WEN Yan
    2018, 5 (4):  266-273.  DOI: 10.12087/oeet.2095-7297.2018.04.08
    Abstract ( 339 )   PDF (4808KB) ( 66 )  
    Semi-submersible platform is a new type of deepwater floating platform, which can be used for oil and gas exploration, development and production in the South China Sea. Steel catenary risers (SCRs) are widely used in deepwater applications due to the relatively simple structure, economy and reliability. The strength of SCR is usually influenced by environmental load and platform movement. Whether the strength meets the requirements is related to the production safety of the platform, so the study of riser strength is crucial. We mainly introduce the layout and configuration of riser, as well as the design method and key technologies of riser, and study SCR strength for the application of SCR to semisubmersible platform in the South China Sea. The strength analysis results of 18-inch riser are given as an example, which provides a good reference for the engineering design of riser.
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    Application of Three-Dimensional Coordinate System to Dimensional Control of Large-Scale Modules
    LIU Rong-kun, YANG Qing-feng, LI Jia-jun, CAO Hong-tao, WANG Xin, WANG Tian-yi, JING Peng
    2018, 5 (4):  274-277.  DOI: 10.12087/oeet.2095-7297.2018.04.09
    Abstract ( 249 )   PDF (1554KB) ( 40 )  
    For large-scale ocean engineering modules, the construction method is usually pre-fabricating in pieces and field-assembling on site. About the dimensional control, there are more control points for the structure and stricter tolerance for attached pipe docking because of the complicated structure and huge overall size. Taking Ichthys liquefied natural gas (LNG) land terminal project which was built on COOEC Qingdao yard as an example, dimensional control is applied to structure pieces and the best-fit center line is marked on them in the pre-fabrication process. Three-dimensional coordinate system control network is established on the final assembly site. According to the system, the positioning and dimensional control of structure pieces, as well as those of the pipe docking, are achieved using the best-fit center line. The three-dimensional coordinate system can effectively ensure the accuracy of the module in the field-assembly process and control the error accumulation, which provides experiences for the dimensional control of large-scale modules in the future.
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    Research on Allowable Deflection Envelope of Barge/Yard Skidway During the Skidded Loadout of Jacket
    HUANG Huai-zhou, LIU Zhao, LIU Yu-xi
    2018, 5 (4):  278-282.  DOI: 10.12087/oeet.2095-7297.2018.04.10
    Abstract ( 305 )   PDF (2414KB) ( 62 )  
    Skidded loadout is the most common loadout method for deepwater jackets. During the skidded loadout of jackets, it is very important to keep the elevation of the barge skidway as close as possible to that of the fabrication yard skidway. Otherwise, large deflection and shear force will be induced in the jacket. Based on the strength requirements of the jacket, barge and yard skidway, the allowable deflection between barge and yard skidway is analyzed for every step of the jacket skidded loadout operation. Finally, the allowable deflection envelope of barge/yard skidway is produced, which will be the guideline for the development of the ballasting scheme of barge loadout. This research will provide reference for similar jacket skidded loadout projects.
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    New Solution to Low-Temperature Refrigeration Air Conditioner in Electric Room of Bohai Sea Platforms: Refrigeration Liquid Pump Energy-Saving Technology
    LU Cun-cai, TU Yu-qiang, LI Xiao-guang, YU Guo-jie
    2018, 5 (4):  283-287.  DOI: 10.12087/oeet.2095-7297.2018.04.11
    Abstract ( 332 )   PDF (1702KB) ( 44 )  
    On the oil platforms in the Bohai Sea, when air-cooling air conditioners run at low temperature, problems such as hard to start, hard to run in steady condition and high energy consumption etc. may appear. Although fresh air duct type air conditioners can solve the problem of low-temperature refrigeration in room, they also have some problems such as large area occupation, high indoor temperature fluctuation and poor comfortableness. We introduce the system composition, working principle and technical features of low-temperature refrigeration liquid pump energy-saving technology, and analyze its energy-saving principle. This technology could provide a new solution to the low-temperature refrigerating problem in electric room of Bohai Sea platforms.
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    Research on Ship Intelligent Coating Production Line
    QIN Hao-ran, WANG Yi, ZHONG Qing-wei, DONG Hao
    2018, 5 (4):  288-292.  DOI: 10.12087/oeet.2095-7297.2018.04.12
    Abstract ( 290 )   PDF (4184KB) ( 56 )  
    At present, there are many problems in China's ship coating production, such as the low level of intelligence and information technology, high manual management costs, low operating efficiency, and low energy utilization. Aiming at these issues, we carry out the research on intelligent coating equipment, coating data integration processing, refined production management system and energy management system. Through the research of intelligent coating, a complete set of shipbuilding intelligent coating production line is established, with field bus control technology and advanced wireless communication technology being the core of control. This production line can be duplicated and popularized. The research results are piloted at Shanghai Waigaoqiao Shipbuilding and Offshore Co., Ltd.
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    Contents of Vol.5, No.4, 2018
    OEET Editorial Office
    2018, 5 (4):  4001-4002. 
    Abstract ( 98 )   PDF (199KB) ( 41 )  
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