纵观世界工业的发展趋势,从批量流水定型生产方式向适应多元变型的柔 性生产方式转变已成定局;再看我国船舶行业的发展,沿海和内河中小型船厂 造船模式的改造已迫在眉睫。 一种极为灵活的修造船企业模式正在悄悄地取代 传统的修造船企业模式而引起造船生产组织的一场变革,而气囊下水正是在这 场变革中应运而生的高适应能力的“柔性下水技术”。 目前,船用气囊下水工艺技术已非常成熟,两项船用气囊标准:《船舶上排、 下水用气囊》CB3795-1996 和《船舶用气囊上排、下水工艺要求》CB3837-1998 的颁布,更是为船用气囊下水工艺提供了理论依据。但随着采用气囊下水船舶 尺度的增大,下水过程中的不确定因素增加,船用气囊下水的风险也随之增大, 因此要解决下水安全问题这一发展瓶颈,就必须不断提高气囊的承载能力和制 定更加合理的下水方案。为此,本文围绕气囊的力学计算和下水工艺方案的制 定展开讨论,并对现有气囊技术水平下的下水船重界限做出预估,以期达到提 高气囊的下水能力,增加这种柔性下水方式的经济性和安全性的目的。 本文首先以自由状态下气囊受压前后主应力变化为依据,讨论内压的变化 规律,研究单个气囊的技术参数和各参数间的相互关系,并采用有限元方法对 气囊的强度理论研究进行了初探,为后续下水计算做准备。 其次,讨论气囊下水工艺两个阶段的实际操作和技术要求,研究气囊下水 第二阶段船体的运动和受力情况,并分别采用传统静力学方法和改进后的弹性 计算方法,解决尾浮时艏部气囊的超负荷承压的计算。 再次,是本文的重点:在前两章研究的基础上,以15800t 散货船实船为 例,设计不同的下水工艺方案,并从安全性、经济性、合理性三个方面对不同 方案进行比较,进行方案选优。 最后,总结本文研究的主要结论,提出研究中存在的不足之处,并指出进 一步研究的发展方向。
关键字:柔性下水技术,船用气囊下水工艺,承载能力,有限元分析,弹性计 算方法,优化方案
Abstract
Lets look at the developing trend of the world industry,the diversified soft mode of production must be instead of the batch flowline production.The small and medium shipyards must transforn the shipbuilding mode along the coast and river in the internal ship industry of our country.The conventional shipbuilding mode has being changed by an new flexible mode which will arousing a transform of shipbuilding production organization.Ship launching with airbag which is a flexible technology of high adaptability emerges as the times require along with the transform. Although the technology of ship launching with airbag is perfect at present,it has higher risk of dangerous along with the augment of launching ship's weight and the increasing of the indeterminate factors.We must advance the loading carrying capacity of airbag and make more reasonable launching project to settle the safety problems which restrict the development of this flexible technology.So this paper discusses the airbag's mechanic calculation and how to make the launching project. For the intent of improving the launching carrying capability and the economical efficiency it also estimates the highest launching weight under the technical level in existence. First according as the main stress changing when the airbag is impressed under the freedom station,this paper discusses the changing rule of the inner pressure and research airbag's limited strength by the finite element analysis method.It also analyzes the technology factors and correlations of the technology factors of the single airbag to prepare for the later calculations. Secondly this paper discusses fact operations and technology requirements during the two steps of the launching courses.It also analyzes the movements and forces of the hull during the second step and calculates the exceeding loading of the airbag under the stem when the stern is floating by two manners of the traditional static calculation and improving elastic calculation.
Thirdly this paper designs different process programs for the 15800T Bulk Carrier and optimizes the project considering the safety and the economical efficiency in the base of two before chapters.It is also the emphasis of the paper. Finally summarize the conclusions and the defects of the research and indicates the development direction of the further research.
Key words: flexible launching technology,ship launching with airbag technology, loading carrying capacity,finite element analysis,elastic calculation method, optimize project
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