【作者】 甄亮；

【导师】 高金吉； 黄汉雄；

【作者基本信息】 华南理工大学 ， 机械设计及理论， 2012， 博士

【摘要】 整体多层夹紧式高压容器是一种使各包扎层板纵、环焊缝均错开的新型多层结构,它除具有多层包扎式容器所具有的优点外,另一突出优点是避免了对容器的制造质量和安全有重要影响的深环焊缝,极大的减少了高压容器的薄弱环节,提升了容器的承载能力和安全系数,同时还具有机械化程度高,加工制造方便的优势。由于整体多层夹紧式高压容器的安全性和制造的方便性,它受到国内外的高度重视,但其在包扎制造过程中产生的预应力及预应力对容器使用过程的影响研究还很不完善,迄今为止,包扎制造过程中产生的预应力并没有得到很好地利用。因此,开展整体多层夹紧式高压容器预应力的研究和建立相应的设计方法对其工程应用具有重要的意义。本文以弹塑性理论为基础,构建了整体多层结构压力容器内筒与层板的力学模型,深入分析并提炼得到影响预应力的主要因素,研究包扎夹紧力与预应力的关系,揭示多层包扎容器预应力分布的一般规律；通过数值模拟和对整体多层包扎容器的水压试验和爆破试验研究,探讨了超水压试验与层间预应力的关系,为整体多层夹紧式高压容器预应力的合理应用建立完整的理论体系。本文的主要工作和结论如下：1)建立了整体多层夹紧式压力容器的包扎夹紧力学模型,研究得到该结构压力容器预应力沿壁厚的分布规律,内壁面为压缩应力,外壁面为拉伸应力,且内壁面的压缩应力逐步阶梯式上升为包扎层板的拉伸应力,径向应力在环向应力为零的区域达到最大值。2)通过内圆筒、层板力学模型为基础分析,提炼得到了多层结构参数此参数是一个仅与多层包扎容器结构有关参数,能直接表征多层包扎容器的预应力情况,当多层包扎结构压力容器的包扎层板超过6层时,容器壁厚可减少12%以上。3)得到容器层板包扎夹紧应力的上、下限约束条件。上限约束条件是确保层板夹紧应力集中部位不出现屈服；下限是确保第一层包扎层板始终保持拉伸预应力，以使层板不出现滑移。4）层板与内圆筒的接触是预应力的源头，在不改变本质力学关系前提下简化接触面情况，得到了局部接触力学模型，并计算获得了接触压力和接触半径的解析解。5）由于预应力及层间间隙的存在，常规水压试验不能达到预应力均匀分布的预期目标。论文通过理论与试验，分析验证了多层包扎结构容器的超水压试验的最佳压力范围为1.9-2.0倍设计压力；超水压试验不仅调整了整体多层夹紧式高压容器的预应力分布，同时还有提升容器承载能力的作用。6）论文建立了整体多层夹紧式高压容器的局部接触、整体接触和多层结构超水压试验的数值模拟计算模型，通过数值模拟获得的了接触压力与接触半径的数值解，与接触压力和接触半径的解析解误差分别为5%和11.9%；整体接触模型的接触压力数值解与解析解误差在3%以内；超水压试验数值模拟计算显示内圆筒应力水平下降7%左右，当超水压达到2.0倍设计压力，整体多层夹紧式高压容器内圆筒及第一层包扎层板将出现屈服。7）通过对整体多层夹紧式试验容器分别以1.25，1.3，1.6，1.75倍设计压力进行超压试验，并进行了内外壁的应力测试，内壁实测应力与解析解有较好的符合性和再现性，1.45倍水压时内壁局部点发生屈服，进行超水压试验范围使容器内外壁应力得到了调整，应力分布趋于均匀；外壁应力有较多的储备能力，容器的安全可靠性提高。另外，高压容器密封泄漏可以采用环氧树脂胶进行补救。8）容器爆破试验证明整体多层夹紧式高压容器有较高承载能力，实测爆破压力值与解析值都大，其爆破安全系数为3.16，爆破压力实测值与解析计算值相比的最大误差是第三强度理论，为26.7%。其他公式获得的爆破理论值与实测值之间最大误差均不超过15.4%。更多还原

【Abstract】 The integrated multilayer clamping high pressure vessel is a new kind multilayer structure that the longitudinal&circumferential welded seams of the layers are staggered. The deep circumferential welded seams are avoided, and it is very important for the vessel quality and safety. The other advantages of this type of pressure vessel are as follows:less thickness, higher manufacture efficiency, and easy to fabricate.The research of the integrated multilayer clamping high pressure vessel is emphasiazed, but the preload stress of the layer clamping&wrapping is seldom studied. The study and the design method of the preload stress of integrated multilayer clamping high pressure vessel have great significance.The dissertation establishes the mechanics model of the inner shell and the layer based on the elasto-plasticity theory, and the main influence factor is deduced to study the relationship between the clamping force and the preload stress. The mechanics model shows the general rule of the preload stress distribution. The numerical&experimental studies are employed to research the hydrostatic experiment and the blast test, and the super hydroastatic test and the layers preload strss are also studied. The main work and the conclusion are as follows:1) The mechanics model of integrated multilayer clamping high pressure vessel is built, and the preload stress distribution along the vessel thickness is obtained. The inner wall preload stress is compression stress and the outer wall preload stress is the tensile stress. The compression stress is steped increasing to the tensil stress through the vessel thickness, and the radial stress reachs the maximum value when circumference stress is zero.2) The multilayer structure parameter,, is deduced from the mechanics model, and it is a parameter only related with the multilayer structure. The parameter indicates the multilayer pressure vessel preload stress distribution. The thickness ofthe multilayer vessel decreases12%, taken into account the multilayer structureparameter, when6layers are wrapped to the inner shell.3) The restriction condition of the layer wrapping&clamping. The upper limitof the layer wrapping&clamping stress is that the layer is not yielded, and the1stlayer maintains the preload tensile stress to avoid the layer slipping is the lower limit.4) The contact between the layers and the inner shell is the source of the preloadstress. The local contact mechanics model of the layer are built with the simplifiedboundary condition, and the formulas of the contact pressure&contact radius arededuced.5) The traditional hydrostatic test cannot adjust the preload stress adjustmentbecause of the preload stress and the gaps between the layers. The dissertationdeduces that the optimization hydrostatic pressure is1.9-2.0times design pressure,and the super hydrostatic test can redisreibute the preload stress, and the loadingcapacity of the pressure vessel is also improved.6) The local contact Finite Element Analysis (FEA) model, the integratedcontact FEA model and the multilayer structure super hydrostatic test FEA medoel arebuilt. The local contact FEA model result shows that the contact pressure errorbetween the analytic value and the numerical value is5%, while the contact radiuserror between the analytic value and the numerical value is lower than11.9%. Theintegrated FEA model obtain the numerical contact pressure has3%error withanalytic contact pressure. The super hydrostatic test FEA model shows that inner wallstress decrese7%, and the inner shell and the1stlayer yields when super hydrostaticpressure is2.0times of design pressure.7) The super hydrostatic test is performed with integrated multilayer clampinghig pressure vessel in1.25,1.3,1.6,1.75times design pressure, and the inner&outerwall stress are measured. The measured inner wall stresses have good agreement withthe analytic solution. The local point of inner wall yields in1.45times design pressure.The preload stress is adjusted with the hydrostatic test, and the outer wall stress haslots of loading potential to enhance the pressure vessel safety. The epoxided resin can be used in the high pressure sealing leakage.8) The blast test shows that the integrated multilayer clamping high pressurevessel have higher loading capacity. The measured blast pressure is higher than theanalytic solution, and the blast safety factor is3.16. The largest error between themeasured blast pressure and theanalytic blast pressure is26.7%with the3rdstrengththeory, and other errors are lower than15.4%.更多还原