挂舵臂结构裂纹的修理

文章通过对船舶挂舵臂处裂纹产生的原因进行分析,对挂舵臂处结构进行了改进,为局部受力过大处的结构设计提供参考;并对修理过程中焊接变形的控制以及修理过程中施工困难的具体情况,提出了控制变形的措施及相应修理工艺。     

32万吨原油船挂舵臂铸造检验

32万吨挂舵臂是目前中国船级社检验的最大船用铸钢件,具有产品结构复杂、体积庞大、检验标准高、生产工艺难度大的特点。目前该挂舵臂已经完工,符合产品检验要求,在这里通过建造过程,对其检验的要点进行总结。     

无损探伤与船舶检验

在船舶建造和检验中,无损检测已经成为船厂、船东和验船师保证船舶质量和设备安全运行的重要手段。CCS《钢制海船入级规范》(2006)及《材料与焊接规范》(2006)对无损检验也有大量涉及,如船舶在建造开工前,船厂、验船师应对无损探伤图、无损检测人员资格记录,无损探伤工艺文件进行确认;舵     

挂舵臂的管极电渣焊工艺

我厂为了将约15吨自重以及承受37.7吨·米的扭矩和相当弯矩的玛琳纳舵固定悬挂在1～4号肋位的船艉处,采用了挂舵臂结构。布置情况如图1所示。为了减轻挂舵臂的自重和降低造船成本,仅在上下舵钮处采用了ZG25铸钢板组合焊接结构。     

船用铸钢件的焊补

现代造船用钢除了钢板、型材、棒材等轧钢件外,还要用一定数量的铸钢件.船体用的艉柱、舵叶、螺旋桨和挂舵臂等多采用的铸钢件.这些铸钢件是保证船舶航行的重要构件,必须具备良好的铸造性能、切削性能和一定的力学性能.     

挂舵臂外形改进

为消除钢板挂舵臂的制造困难点,提出一种新的挂舵臂外形,即折线型外形,侧板的外表面由平面、圆弧面和圆柱面连接而组成。相对于常规外形,该折线型外形的优势是:能在建造过程中减少工作量,从而降低生产成本;对挂舵臂的强度和船体阻力无不利影响。     

挂舵臂弹性支撑的舵-舵杆系统直接计算分析

大型船舶半悬挂舵的舵—舵杆系统设计中,应考虑挂舵臂对其弹性支撑作用进行直接计算分析。介绍了采用挪威船级社(DNV)3D-BEAM软件对挂舵臂弹性支撑的舵—舵杆系统的力学模型进行受力计算和分析。     

舵杆直径的选择及其与挂舵臂的匹配分析

单舵销半平衡舵的舵杆与挂舵臂的匹配设计需要提取的数据量较大，计算及优化过程也较为复杂。依据该舵系的力学模型所建立的电算方法，对舵杆与挂舵臂的强度匹配及其影响因素作较深入的分析，并从舵系的安装、舵杆的变形等角度提出了对舵杆直径的选择建议，得出的方法和结论可供参考。     

双舵销舵系实用计算

按ABS／DNV规范，对挂舵臂支撑的双舵销舵系需用直接计算法计算各支撑点的受力。以确定相应构件的材料和尺寸。本文提供了挂舵臂支撑的双舵销舵系的实用力学计算模型及其线性方程组解，并对其作了简要介绍和分析。采用本计算模型编制程序电算所得结果已应用于实船设计并为船级社所认可。     

船舶舵装置结构三维有限元仿真研究

在船舶舵装置结构系统的强度分析中,以往采用解析法进行计算分析,在计算中必须引入大量的简化假设,导致其结果精度较低。现针对某船舵装置系统结构采用三维有限元进行离散,通过选取适当单元,使用内部多点约束和接触算法、建立包括舵杆、舵板、半悬挂舵臂和船体舵机舱结构的完整有限元模型;使模型与结构的相似度较传统方法有很大的提高。最后通过施加流体软件计算的水动力载荷分析舵装置系统各部分的应力和变形,从而对结构的强度作出评价。     

舵系直接计算法设计

为了在项目设计初期快速准确地对舵装置进行设计和确定主要构件尺寸,对几个主要船级社规范中对舵系的相关计算要求进行研究和对比,总结其共性要求,并得出结论:需要通过直接计算方案进行舵装置的设计。根据结构力学的模型分解和规范校核等方法,验证可直接用于舵装置设计和确定主要构件尺寸的直接计算方法。     

挂舵臂支撑的半悬挂平衡舵舵杆的受力计算

大型船舶上的舵除了上、下舵承外，还设置有挂舵臂，各国船级社认为悬挂在船体上的挂舵臂应视为弹性支座对舵杆进行直接计算。本文介绍了这种类型平衡舵舵杆的受力计算方法。     

Practically applicable devices for blocking the gap flow of a horn rudder to reduce rudder cavitation and their verification through numerical simulations

Rudder cavitation causes serious damage to the rudder and affects the safety and cost-effectiveness of a ship. In recent applications, a semicircular prismatic bar protruding beyond the concave surface of the horn facing the gap, located along the center-plane of the rudder, has been used to lessen the gap flow between the horn and the movable portion of the rudder system. Previous numerical studies with this single bar indicate that it can noticeably reduce rudder cavitation. In the present study, a pair of bars for blocking the vertical gaps, which are attached symmetrically to the center-plane on opposite convex surfaces of the movable portion, is suggested for circumventing the difficulties that arise in the practical application of single centre bars. Placed near the outer edges of the gap, the bars are are easily accessible at the maximum rudder angle to allow simple installation during routine ship maintenance. An additional blocking disk is inserted on top of the pintle block, blocking the horizontal gaps. Three-dimensional computations are conducted with these combined devices and the results show that the devices are remarkably efficacious in reducing rudder gap cavitation.     

对IACS《散装货船共同结构规范》中有关舵设备的几点意见

对《散装货船共同结构规范》（2006）舵设备部分有关舵面积,有舵杆筒悬挂舵的计算模型,锥形连接器的锥面预加压力及其许用压力以及半平衡舵强度校核等提出了作者的看法,望能获得IACS和船级社的关注。     

40600dwt散货船舵的直接设计

在舵的设计过程中,为了使舵满足规格要求,使舵与船能更好地匹配,采用了直接计算法确定半悬挂平衡舵的构件尺寸,并对其强度进行校核。     

A suggestion of gap flow control devices for the suppression of rudder cavitation

This paper presents the numerical analysis of rudder cavitation in propeller slipstream and the development of a new rudder system aimed for lift augmentation and cavitation suppression. The new rudder system is equipped with cam devices which effectively close the gap between the horn/pintle and movable wing parts. A computational fluid dynamics code that solves the Reynolds-averaged Navier–Stokes equations is used to analyze the flow field of various rudder systems in propeller slipstream. The body force momentum source terms that mimic flow field behind a rotating propeller are added in the momentum equations to represent the influence of the propeller and its slipstream. For detailed explication of the new rudder system’s lift augmentation and cavitation suppression mechanism, three-dimensional flow analysis is carried out. Simulations clearly display the mechanism of the lift augmentation and cavitation suppression. The computational results suggest that the Reynolds-averaged Navier–Stokes-based computational fluid dynamics reproduces the flow field around a rudder in propeller slipstream and that the present concept for a cavitation suppressing rudder system is highly feasible and warrant further study for inclusion of the interaction with hull and mechanical design for manufacturing and operations.     

单舵销挂舵臂支撑舵受力计算

根据ABS和GL规范提供的单舵销挂舵臂支撑舵的计算模型，运用平面弯曲绕曲线近似方程式和弯曲变形的叠加原理推导出舵的剪力、弯矩和轴承反力的直接计算公式，并整理出计算程序。通过举例计算，证明本计算方法是可行的。