Review of Anti-Sway Control Algorithms for Bridge Cranes

 

LU Fengjiao¹, LIU Haijiang², YOU Lei³, SUN Yuguo¹

(1. School of Optical-Electrical and Computer Engineering,

Universityof Shanghai for Science and Technology, Shanghai 200093, China;

2. TongJi-Taicang Institute of High Technology, Taicang 215400, China;

3. Rainbow-Cargotec Industries Co., Ltd., Shanghai 200120, China)

 

Abstract: Based on the domestic and foreign researches concerning anti-sway control technologies for cranes, this paper gives a systematic summary on the development of anti-sway control technologies for cranes. The design principles of commonly used control algorithms are introduced along with the brief analysis and comments. The advantages and disadvantages of different control algorithms as well as their applicable conditions are compared and the future research directions of anti-sway control algorithms for bridge cranes are proposed. This provides the theoretical reference for the research in the field, and is helpful for the crane system to face more complex working environment and to serve the industrial development.

Key words:bridge crane; anti-sway control; control algorithm; mathematical model

 

 

 

Jackson Submarine Hull Complying with Hydrostatic Regulations

 

QI Xiang¹, TANG Xiao², QI Huan^3,4

（1. China Ship Research and Design Center, Wuhan 430064, China;

2. Early Warming Institute of Air Force, Wuhan 430012, China;

3. Naval University of Engineering, PLA , Wuhan 430032, China;

4. Wuchang Shouyi University, Wuhan 430064, China）

 

Abstract: This paper analyzes several representation models of control equation for Jackson submarine hull, where two of the shape factors can be obtained by solving a set of simultaneous equations for the required displacement volume and longitudinal center of buoyancy, while the other two can be obtained through an optimization method. The feasibility of the method is validated by a practical example. The result shows that the method can be used to establish the mathematical hull lines, and can be further used for multi-disciplinary design optimization.

Key words:Jackson hull line control equation; submarine shape; hydrostatic conditions; SUBOFF submarine model; optimization method

 

 

 

Design of Self-Propelled Hyperbaric Lifeboat for Saturation Diving

 

LYU Wenya^1,2, CHEN Xinquan^1,2, YANG Qi^1,2,3, HAN Jie⁴, ZHAO Jianguo⁴

(1. a. State Key Laboratory of Ocean Engineering; b. School of Naval Architecture, Ocean & Civil Engineering,

ShanghaiJiao Tong University, Shanghai 200240, China;

2. Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240, China;

3. Shanghai Jiao Tong University Underwater Engineering Institute Co., Ltd., Shanghai 200231, China;

4. Qingdao Beihai Shipbuilding Heavy Industry Co., Ltd., Qingdao 266520, China)

 

Abstract: The Self-Propelled Hyperbaric Lifeboat (SPHL) used in saturation diving is a dedicated vehicle for the evacuation of divers under high pressure. The paper discusses its main design features according to the rules and regulations, and analyses its intact stability and flooded stability. The self-righting features and the Motion Sickness Incidence (MSI) of SPHL are investigated based on the characteristics of enclosed hull, large draft and high gravity center. It is found that the self-righting time is only influenced by the height of gravity center in case the hull shapes are similar. The high MSI in heavy waves can be reduced effectively by reducing speed.

Key words:saturation diving; hyperbaric lifeboat; self-righting; flooded stability; MSI

 

 

 

Numerical Simulation of Leg Section Falling

on the Helicopter Deck of a Jack-up Platform

 

ZHANG Xiaoying^a, HU Zhe^a, LIN Guozhen^a,b, KANG Jieyu^a, CHEN Wu^a,b

（a. Marine Engineering Institute;

b. Key Laboratory of Naval Architecture and Ocean Engineering of Fujian Province,

Jimei University, Xiamen 361021, China)

 

Abstract: Objects falling incidents often occur in the lifting operation of platform installation, which poses a great threat to the safety of both personnel and property. Based on nonlinear finite element theory and the collision contact algorithm, this paper establishes the helicopter deck model of a jack-up platform to simulate the collision of a leg section falling onto a helicopter deck during the lifting process, and to study the pattern of stress distribution, structural damage, system energy, collision depth and collision force. The variations of collision force and system energy under different impact velocities are discussed, and the critical impact velocity with no plastic deformation of the helicopter deck is obtained, providing reference for the lifting operations of leg sections.

Key words:Jack-up platform; collision problem; finite element analysis; ANSYS/LS-DYNA

 

 

 

Fatigue Risk Existed in the Design of

Traditional Marine Scupper and Its Improvement

 

ZHAO Wenbin, GAO Feng, HUA Kang

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

 

Abstract: Finite element method is used to calculate the hot-spot stress concentration factor (SCF) of the scupper nodes designed in the traditional way. It is found after calculation that the scupper nodes have extremely high SCFs, which are unfavorable for the fatigue strength. This means that the traditional scupper nodes are not properly designed. To solve the problem of high hot spot SCF, an improvement scheme for scupper nodes is proposed. The result of finite element analysis shows that the improvement scheme can effectively reduce the scupper hot spot SCF, thus reducing the fatigue damage risk.

Key words:hot spot stress concentration factor; scupper; fatigue strength

 

 

 

Design and Strength Analysis of Inclined Ladder Hole

in VLCC Cargo Hold

 

ZHU Peipei, JIAO Lingling, SHENG Lixian

（Shanghai Waigaoqiao Shipbuilding Co., Ltd., Shanghai 200137, China)

 

Abstract: Ladders and ladder holes should be properly arranged in the ship channel design to make maintenance and repair convenient and to comply with the structural strength regulations. Focusing on the design of inclined ladder hole on a Very Large Crude Carrier (VLCC), this paper carries out preliminary studies on how to properly arrange the inclined ladders and holes, how to determine the dimensions of the ladder holes, how to evaluate the ladder hole’s strength based on the finite element method and how to strengthen the structures accordingly. This study provides reference for the design of inclined ladder hole and the analysis of the opening structural strengthening for subsequent ships of similar types.

Key words:ladder hole design; strength analysis; finite element method

 

 

 

On-deck Container Lashing Design for

Large Domestic-trade Container Vessel

 

LI Feng, LIU Xiangdong, SHEN Lining

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

 

Abstract: This paper studies the on-deck container lashing design of large domestic-trade container ships based on a 4200 TEU domestic-trade container vessel. Three lashing arrangements are proposed. Lashing calculations are conducted for 20ft and 40ft container stacks of the three lashing arrangements under various conditions including five container bays, two GM values, and with or without wind pressure. Distributions of the maximum achievable stack load along ship length and the container weight distributions of 20ft and 40ft inner container stack under the ultimate maximum stack load condition of each lashing arrangement are obtained. The stack-calculation results are analyzed to ensure enough loading capacity and two of the lashing arrangement are confirmed to be feasible. Comparison of the container weight distributions under the ultimate maximum stack load condition of each lashing arrangement proves that the lashing bridge has beneficial influence on the loading flexibility. Meanwhile, the advantages and disadvantages of the two lashing arrangements are compared in terms of economic performance and lashing operation workload.

Key words:domestic-trade container ship; lashing arrangement; lashing calculation; stack load; container weight distribution

 

 

 

Force Analysis of the Anchor Winch Drum and

Its Brake Mechanism Based on NX NASTRAN

 

LI Wenzhao

（Shenhua Huanghua Harbour Administration Co., Ltd., Cangzhou 061113, China)

 

Abstract: A 3D assembly model for the anchor winch and its brake mechanism of a tugboat is established using the NX software, then the finite element analysis on the backward towing and the load holding conditions are performed using the pre/post processing modules in the software. The result shows that the brake mechanism may deform and fail under the load holding condition and the conclusion of software analysis is basically consistent with that of real ship. In addition, the paper points out the validity of NX software in modeling of equipment components, and puts forward optimization suggestions for fault analysis.

Key words:tugboat; anchor winch; finite element analysis

 

 

 

Power Station Configuration for Very Large Container Vessel

 

FU Xiaohong, XIA Jun, ZHOU Yilong

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

 

Abstract: As the main engine and electrical power station on very large container vessels are of large capacity and the global awareness of marine and atmospheric environment protection is increasing, the power station configuration has to be optimized to save energy and reduce emission. This paper elaborates the hybrid power station consisting of diesel engine generator, Power Take-Off (PTO) generator and Power Take-In (PTI), steam turbine generator and exhaust gas booster generator. The control logic of power management system for this type of power station is analyzed, and the design of such hybrid power stations provides a more energy efficient option for very large container vessels.

Key words:very large container vessel; green ship; hybrid power station; power management system

 

 

 

Rules and Regulations for Ships Sailing

in the Arctic Northeast Route

 

XIA Dengzhu

（Shanghai Waigaoqiao Shipbuilding Co., Ltd.,Shanghai 200129, China)

 

Abstract: This paper studies the rules and regulations applicable for ships sailing in the Arctic Northeast Route, and elaborates the concept of the Polar Code, the rules of navigation in the water area of the Northern Sea Route, the requirements concerning Polar Class and the guidelines for ships operating in polar waters. The study provides effective guidance on the design, construction, inspection and operation of ships sailing in the Arctic Northeast Route, which is helpful for the understanding of the relationships among the relevant rules and regulations.

Key words:Arctic Northeast Route; polar class; polar code

 

 

 

Strength Analysis of the Jack-up Platform Helideck Based on CAP 437

 

SUN Yuanzhang¹, Ou Shubo¹，YUE Xinghua², GONG Qingtao¹, GUO Xinqiang¹

（1. China Merchants Jinling Shipyard (Weihai) Co., Ltd., Weihai 264200, China;

2. China Classification Society Dalian Branch, Dalian 116013, China）

 

Abstract: This paper takes a 121.9m jack-up platform as the example to explain the helideck designed according to  Sikorsky S-92 helicopter whose maximum take-off weight is 125.859kN and the distance between the two landing gear action-points is 3.84m. Using Det Norske Veritas (DNV) structural analysis software Sesam and based on the British Civil Aviation’s Offshore Helicopter Landing Areas - Guidance on Standards (CAP 437) which is more stringent than the classification societies’ requirements, the finite element analysis and computation are performed for the helideck structure under the combined loading conditions closest to the actual situation. The process and method provide reference for the design and operation of jack-up platform helidecks.

Key words:jack-up platform; helideck; structure strength; finite element analysis; CAP 437

 

 

 

Meticulous Dispatching Management of

Ship Painting and Sandblasting Operation

 

WANG Dong^1,2, CHEN Songpei², LIU Jianfeng²

(1. School of Naval Architecture and Ocean Engineering, Jiangsu University of Science and Technology,

Zhenjiang 212003, China; 2. Shanghai Waigaoqiao Shipbuilding Co., Ltd., Shanghai 200063, China)

 

Abstract: Sandblasting operation is an important step of ship painting operation. In order to realize meticulous dispatching management of painting operation and improve painting efficiency, this paper studies the meticulous dispatching management of ship painting and sandblasting operation. The influencing factors on the compartment subdivision of hull block sandblasting operation are studied based on the analysis of sandblasting operation to properly divide the regions and set the quotas. A practical application to a typical hull block has been validated, and proposals for painting design improvement are put forward to provide reference for the meticulous dispatching.

Key words: block painting; sandblasting; meticulous dispatching

 

 

 

Application of Factor Sensing Technology

in Shipbuilding Production Management

 

CAI Kaiqian, ZHANG Yi, SHEN Han

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

 

Abstract: This paper elaborates the development of factor sensing technology and its application in production management. Taking the management of welding machines in Shanghai Jiangnan Changxing Shipyard as the example, it analyses the issues related to the existing production control mode of the leading domestic shipyards. The factor sensing network for ship production process is discussed in accordance with the layout of ship production factors to enhance the factor information collecting ability and to establish the new intelligent management and the control mode of “factor sensing - intelligent decision making - precise execution” to make ship production management and control in the construction more convenient and leaner.

Key words:intelligent manufacturing; production management and control; factor sensing

 

 

 

Application of Dijkstra Algorithm in Ship Evacuation Analysis

 

LIU Chenming¹, CHEN Miao², DU Shixin², LIANG Yuanhua¹

（1. ChinaClassification Society, Beijing 100007, China;

2. HarbinEngineering University, Harbin 150001, China)

 

Abstract: In order to determine ship evacuation capability efficiently and accurately, this paper analyzes in detail the modelling and calculation methods of the fluid mechanics model specified in MSC.1/Circ.1533, and applies them to the ship evacuation capability assessment according to MSC.1/Circ.1533. The calculation program is developed by coupling Dijkstra algorithm with the fluid mechanics model in MSC.1/Circ.1533. A passenger ship is taken as the example, and Dijkstra algorithm is used to evaluate the ship’s evacuation capability. The result shows that the evacuation capability calculation based on Dijkstra algorithm can increase the efficiency of evacuation capability calculation, and effectively analyze the rationality of the general arrangement.

Key words:evacuation capability assessment; Dijkstra algorithm; MSC.1/Circ.1533; simplified fluid mechanics method; general arrangement optimization