Discussion on Design Philosophy of Minimal Platform for Marginal Oil Field Exploration

 

XIE Bin，TAN Yue，WANG Chun-sheng

（CNOOC Research Institute, Beijing 100027,China）

 

Abstract: Minimal platform is created and developed with a specific historic background where oil and gas industry has been expanding quickly. As offshore engineering technologies are developing, it is necessary to reacquaint the core concept of minimal platform. This paper introduces the definition of minimal platform and unmanned platform, and proposes the basic principles for the general design and the structural design. After analysis, it points out that minimal platform does not merely mean the structure simplification and weight reduction, but also mean a shortened construction period and a low cost offshore installation, and the latter two are the real value coming from.

Key words:marginal oil field; minimal platform; main; design; structure

 

 

 

Key Factors for Design of the Object Towed Underwater

 

WANG Zhi-bo

(Shanghai Ship and Shipping Research Institute, Shanghai 200135, China)

 

Abstract: According to the engineering requirements for the design of the object towed underwater, this paper summarizes the essentials in design of the object towed underwater and the system integration, including structural strength, hydrodynamic performance, dynamic stability, design standardization, transportation, corrosion resistance, towing safety, mass property, and system assembly and testing. The key factors of the above essentials are fully discussed, and the major problems to be solved during design, construction and examination are pointed out.

Key words:design of the object towed underwater; structural strength; hydrodynamic performance; dynamic stability

 

 

Research and Development of Ro-Ro Ships

 

ZHANG Wen-bin，ZHANG Min-jian

（Shanghai Merchant Ship Design and Research Institute, Shanghai 201203, China）

 

Abstract: Both the shipping market and shipbuilding market of Ro-Ro ships are studied with the conclusion that the top seven Ro-Ro ship operators are mainly located in the costal countries of the Mediterranean, the Baltic Sea and the North Sea, whose aggregate lane meters account for 60% of the statistical fleet. The top three Ro-Ro shipbuilding yards are the FSG from Germany, JINLING Shipyard from China and the Hyundai Mipo Shipyard from Korea. Then, the technical features of the Ro-Ro ship operating in the Mediterranean, the Baltic Sea and the North Sea are analyzed based on the differences in ship breadth, maximum drafts, number of deck levels, activities decks, springboards, service speeds and etc. As a result, a new generation of Ro-Ro ship to operate in the Mediterranean is developed with 2700m lane length and duel fuel propulsion engine, which meet the requirement for convenient transportation of ro-ro cargos, the phase II of EEDI (Energy Efficiency Design Index) Ro-Ro rules, the low SO_xemission regulations and IMO Tier III NO_xemission standard.

Key words:ship and naval architecture; Ro-Ro ship; research; research and development

 

 

 

Development and Design of a Double Acting Ice Breaking Tanker Operating in the Polar Area

 

TANG Guo-min

（Shanghai Honghua Offshore Oil & Gas Equipment Co., Ltd., Shanghai 201206, China）

 

Abstract: A double acting ice breaking Aframax crude oil tanker is designed in accordance with the climate and ice condition in the Arctic area. At the same time, a northeast route is specially designed for the ship to transport crude oil from the oil fields at British North Sea and Russian Siberia to East Asia during the three months in summer and autumn. For the rest of the year, the ship is operated as a shuffle tanker or a conventional Aframax tanker in the North Sea and Baltic Sea region. This paper elaborates the details of the route, the design concept and the main characteristics of the double acting tanker, as well as its operational efficiency.

Key words:arctic route; northeast route; ice breaking tanker; double acting; design concept

 

 

 

An Active Wave Compensation Method

for the Gangway of Wind Turbine Maintenance Vessel

 

SU Chang-qing，ZHENG Wen-bin，ZENG You-bing，DING De-fu

（Jiujiang Institute of Precision Measurement and Testing Technology, Jiujiang 332000, China）

 

Abstract: This paper introduces a gangway designed with active compensation to meet the requirement of wind turbine maintenance in high seas. The structural design of the gangway is analyzed, and then the computational analysis of the compensation model is carried out. High speed digital signal processor is used as the core of the compensation control system which measures the real-time attitude and heave motions of the maintenance vessel with the motion reference unit, calculates the required stroke of the hydraulic cylinder according to the compensation model, and controls the hydraulic system to realize roll, pitch and heave compensation. It is in this way to maintain the relative distance between the end of the gangway and the base of the wind turbine, and to ensure the safe embarkation of the wind turbine maintainers. Mooring experiment of the maintenance vessel at the quay shows that the system can effectively compensate for the wave influence on the vessel, which well satisfies the embarkation requirement in high seas.

Key words:accessing gangway; accessing gangway system; active wave compensation; motion reference unit

 

 

 

A Research on the Acoustic Fish Herding Technology

 

YIN Yong-qin，LYV You-lin，ZHAO Chuan-da，PENG Wen-lin

（1. CSIC No.726 Research Institute, Shanghai 201108, China;

2. Shanghai Ruiyang Marine Technology Co., Ltd., Shanghai 201108, China）

 

Abstract: In order to solve the problem of mutual interference between human and marine creatures, a highly efficient and environment-friendly fish herding device is developed, which can temporarily herd fishes away from human activity areas, eliminating the potential dangers to offshore operation and protecting fishes from injury. Fishes are sensitive to sound, they will react to displeasing sound and swim away, so the acoustic method is chosen for fish herding, of which the simplest way is to use electro-hydraulic effect to produce broadband composite sound waves to ensure the herding effect.

Analysis on the Combustion Characteristics of

Dual Fuel Engine Under Overload Conditions

 

GE Yue-feng，GONG Xi-wu，ZHANG Heng

（School of Naval Architecture and Ocean Engineering, Zhejiang Ocean University, Zhoushan 316022,China）

 

Abstract: Overload is one of the important loading conditions to be considered in the design and operation of marine diesel engines. In this paper, Chemkin-pro program is used to analyze the combustion characteristics of the dual fuel engine under overload conditions to improve the dynamic property and economic efficiency of the engine, and to make the engine more environmental friendly. It is found that the maximum temperature and the maximum pressure inside the cylinder are decreased and delayed when the methane replacement rate is 70% under overload conditions, but the variation of the temperature and pressure inside the cylinder is almost the same as that with diesel when the methane replacement is 50%. So the conclusion is that 50% methane replacement is more reasonable than 70% replacement under overload conditions, which is beneficial for the dynamic property, economic efficiency and environmental friendliness of the engine.

Key words:dual fuel; diesel engine; overload; combustion characteristics

 

 

 

Analysis on the Engine Propulsion Characteristics of Yacht

Based on VGT Technology

 

GUAN De-liang¹，XIA Qing-liang¹，GAO Zhan-bin^1,2

(1. Marine Engineering Institute, Jimei University, Xiamen 361021, China;

2. Harbin Engineering University, College of Power and Energy Engineering, Harbin 150001, China)

 

Abstract: A complete model of OED483Q variable geometry turbo-charge diesel engine is established with GT-Power simulation software based on the relative engine parameters. The main parameters are validated and calibrated in the model experiment. On this basis, the propulsion characteristics of the OED483Q diesel engine are studied and analyzed along with the experiments, and the effects of Variable Geometry Turbo-charge (VGT) and ordinary waste gas turbo-charge on the diesel engine are compared. The result shows that variable geometry turbo-charge can effectively increase the pressure under low loadings to reduce effective fuel consumption rate and to increase economic benefit. Moreover, it can avoid the overheating of the exhaust gas from the turbo-charge due to the excessive pressure, and thus to guarantee the operation life of engine.

Key words:GT-Power; type OED483Q diesel engine; VGT; propulsion characteristics;experiment

 

 

 

Analysis and Comparison of Main Propulsion Units

for LNG Carrier

 

SONG Dan¹，GUO Qiang²

（1. MAN Diesel & Turbo Shanghai Office, Shanghai201203, China;

2. Shaanxi Provincial Transport Department, Xi’an 710003, China）

 

Abstract: Based on a 174000m³Liquefied Natural Gas (LNG) carrier, this paper studies the functions of propulsion units to find out the most efficient one for the dual fuel engine of LNG carriers. It compares and analyses the efficiency of two popular modern propulsion forms for the dual fuel engines of LNG carrier, i.e. mechanical propulsion and electrical propulsion, with the initial investment cost and operational cost into consideration to provide references for the design and construction of LNG carriers. The result shows that the two-stroke dual fuel mechanical propulsion unit has more advantages over the four-stroke dual fuel electrical propulsion unit in terms of propulsion efficiency, operational cost and initial cost.

Key words:LNG carrier; dual fuel engine; operation cost; initial investment cost

 

 

A Reason Analysis for the Malfunction of Main Engine Fuel

Limiter on an Ore Carrier

 

LIU Yong-xin，KE Xiao-lei，LIU Qing-jiang，WANG Jia-zhi

（Dalian Shipbuilding Industry Co., Ltd., Dalian 116021, China）

 

Abstract: As it is quite difficult to raise the speed of engine at the maximum rpm during the sea trial of an ore carrier and it is frequently trigger the alarm of the monitoring system in the engine room, this paper studies the composition of the fuel limiter of the main engine according to the malfunction phenomenon, the relevant theories of marine diesel engine and the propeller characteristics. When the comparison is carried out between the bench test of main engine and the sea trial, the limitations of the bench test and the multi-factorial influences of the sea trial are exposed, and the reasons behind the engine fuel limiter malfunction are found. Thus the problem is solved and some countermeasures are proposed for the reference of other ships.

Key words:main engine fuel limiter; load indicator; fuel restriction range

 

 

 

Simulation of AIS in Inland Waterway Ship Handling Simulator

 

CONG Lin，REN Hong-xiang，ZHANG Xin-yu

（Key Laboratory of Maritime Dynamic Simulation and Control of Ministry of Transportation, 

Dalian Maritime University, Dalian 116026, China）

 

Abstract: Automatic Identification System (AIS) offers real-time navigation information of a ship and its surrounding ships in inland waterway transportation so it provides strong support for safe navigation. As inland waterway ship handling simulator is commonly used in crew training nowadays AIS simulation equipment becomes even more important. This paper analyzes the functional requirements of Type B AIS for inland waterway applications, in which VC-MFC software is used to establish the AIS simulation software platform, Dynamic Link Library (DLL) is used to design the AIS simulation software framework and some key technologies such as memory share, multiple input switch, distance calculation between two ships and brightness and contrast adjustment achieved by translucent method are used to realize the AIS simulation in the inland waterway ship handling simulator.

Key words:inland waterway ship; AIS; simulation; ship handling simulator

 

 

Design Analysis on the Power Distribution System for

Reefer Containers of Very Large Container Vessel

 

FU Xiao-hong，XIE Song-qing，ZHOU Yi-long，XIA Jun

（Marine Design & Research Institute of China, Shanghai 200011, China）

 

Abstract: This paper analyzes three power distribution systems i.e. radial type, inner-ring type and outer-ring type for the reefer containers onboard containerships, and elaborates the characteristics of each reefer power distribution system from three aspects of reliability, efficiency and installation dimensions. The concept of bus-way technology is introduced, and comparisons between bus-way and cables are made in terms of weight, voltage drop, heat loss, ability to withstand short circuit and installation. It is a prospective study on the feasibility of bus-way application in reefer container power distribution system.

Key words:very large container ship; reefer containership; power distribution system; bus-way

 

 

 

Design and Manufacturing Method for

Welding Pressing Die of Special Hyperbolic Plate

 

WU Zhao-hui，WU Yi-zhong，YU Feng，YIN Qun，QIAN Chun-jun

（Jiangnan Shipyard (Group) Co., Ltd., Shanghai 201913, China）

 

Abstract: Cold-forming by welding compressing die is not only an effective way to shape the hyperbolic plates for special hull regions, but also an effective method to ensure plate forming quality and to realize batch manufacture and takt manufacture. This paper proposes the design optimization method and manufacturing requirements for the mould according to the structural characteristics and welding factors of thick and thin plates made of special material, and presents the manufacturing method of welding compressing die for conventional saddle shape and sail shape hyperbolic plates. The feasibility and reliability of the method is proved when the finite element calculations are combined with manufacturing practice, and the aim of reducing cost and shortening mould manufacturing period is achieved when the key technologies for the design and manufacturing of welding compressing die are summarized. This study provides technical support and technical preparation for the agile construction of high-tech large products.

Key words:hyperbolic plate; cold pressing forming; welding pressing die; manufacturing method

 

 

 

SHAO Guo-qing，ZHAO Yin-ni，SHI Ping，LI Chong-jian

（Dalian Shipbuilding Industry Outfitting Co., Ltd., Dalian 116013, China）

 

Abstract: This paper elaboratesthe flange pre-rotation angle calculation for the pipes welded before bendingbased on trigonometric computing method and normal vector computing method, and suggests to use the sample rod simulation method to verify the result of flange pre-rotation angle calculation according to the pipe bending process of the NC pipe bending machine. In this way, the study lays the foundation for the processing technology of the pipes welded before bending, and improves the quality of the products.

Key words:pipe; flange; welding before bending; pre-rotation angle; calculation; verification; method

 

 

 

Selection and Application of Chinese Branded Small Stud Welding

Machine for the Cargo Tank Construction of LNG Carrier

 

WENG Hong-bing，JIN Ge-tian，WANG Sen

（Hudong-Zhonghua Shipbuilding (Group) Co., Ltd., Shanghai 200129, China）

 

Abstract: In order to reduce the construction cost and to realize the localized supply of equipment for the construction of Liquefied Natural Gas (LNG) carrier, Hudong-Zhonghua Shipbuilding (Group) Co., Ltd. analyzes and investigates the function of the imported stud welding machines to select a welding machine made in China according to the GTT standards. After a series of welding tests and verifications, a Chinese branded stud welding machine is chosen, which meets the actual shipbuilding requirements of the cargo containment system of LNG carrier.

Key words:LNG carrier; stud welding machine; brand selection