微内压储罐罐顶与罐壁连接结构有限元分析

采用有限元应力分析的方法对4种不同的罐顶罐壁连接结构进行了详细应力分析,并进行了对比,达到了结构设计优化的目的。得出如下结论:罐壁承受液压与否对拱顶与罐壁的连接结构应力分布不会产生明显影响,可不考虑罐壁所承受的液压;相同条件下,c型结构与g型结构在4种结构中应力相对最小,二者差别不大,最大相差不足3%;b型结构各应力指标居中;k型结构应力最大。最终分析结果以美国ASMEⅧ-2《压力容器建造—另一规则》规范为依据进行了应力评定。     

成品油罐应力分析及加固技术问题探析

本文将油罐边缘板和全部罐壁看作一个整体进行应力分析,避免了将两者分开而忽视下节点与罐壁变截面互为影响的缺点。并对转移油罐罐壁与罐底结合点附近边缘应力的受力措施进行了分析研究。     

3000立方LNG储罐整体结构有限元静力分析

介绍3000m~3LNG单容式储罐结构特点,使用ANSYS软件分别对内罐和外罐不同工况进行了应力分析,根据应力分布对结构进行了优化,展示了有限元应力分析在解决此类问题的优势。     

溶液罐封头偏置接管应力有限元分析

为了分析带偏置接管的溶液罐封头局部区域的应力分布,对该特殊结构进行三维有限元分析,并且采用分析设计方法对该封头进行强度评定。计算结果显示,最大应力发生在封头接管的边缘焊缝处,在此基础上分别在不考虑焊缝结构和增大局部载荷的条件下进行计算和分析,并对结果进行比较,得到相应情况下的应力分布,为工程设计和应力分析提供参考。     

黄磷集装箱罐检验技术的研究

通过对10英寸黄磷集装箱罐进行有限元应力分析计算,找出了常温环境下装满货物的该罐承受惯性力时的最大应力发生部位;对腐蚀模拟试样进行失重研究,分析腐蚀对黄磷集装箱罐的影响,找出了其易腐蚀部位;对黄磷集装箱罐失效形式的统计,找出了其易失效模式;为黄磷集装箱罐的检验提供了技术依据,从而确保黄磷集装箱罐的安全使用。     

天然气球形储罐开裂原因分析及防治

对天然气球罐的开罐检验中发现一组裂纹,通过对开裂区域的硬度测试、开裂内部腐蚀产物分析及结合天然气气质分析报告。该开裂是有湿硫化氢介质引起的应力腐蚀开裂。针对该开裂产生的原因提出了安装时的要求和开罐检验中的重点检查部位。     

干气压缩机入口缓冲罐接管焊缝泄漏分析及处理

研究了某公司干气回收装置干气压缩机入口缓冲罐接管焊缝开裂泄漏的问题，通过对开裂的接管焊缝进行了切割取样，进行化学成分分析、宏观观测、拉伸试验、冲击试验、金相检验和裂纹附近各区域的硬度检测，结果表明接管材质满足标准。结合活塞式压缩机工作原理，确认该压缩机正常运行中气路管线振动较大，泄漏点的开裂是受应力引起的疲劳裂纹。裂纹部位存在交变应力，这种振动和交变应力促使缓冲罐接管角焊缝开裂。针对管道振动形态采取了多种手段进行减振处理，处理后振动幅值下降了56%，大大降低了干气泄漏着火的风险，满足了装置安全平稳运行的要求。     

喷放罐进料口的应力分析

利用Ansys 12.0对喷放罐进料口进行了有限分析，得到了其受力特性和应力分布规律，并对其进行了应力强度评定。     

大型LNG双燃料动力散货船燃料舱有限元分析

LNG动力船舶的应用已经进入快速发展阶段，其燃料罐的应力分析对保障船舶安全稳定运行起着至关重要的作用。以大型散货运输船LNG供气系统为例，采用ANSYS软件，考虑了船舶运动荷载、温度载荷、压力载荷等因素，在不同载荷工况下对其燃料罐进行了应力分析校核，得出较大应力点，为燃料罐的规范设计提供了理论依据。     

硫化氢罐开裂失效分析

硫化氢罐发生开裂,对该罐开裂原因进行了失效分析。该罐存在三种开裂：容器内硫化氢产生氢原子向钢中扩散并聚集形成氢鼓泡;不同层面上的相邻氢鼓泡裂纹在内压下相互连接,形成氢致开裂;在内压下鼓泡位置产生拉应力,在拉应力和湿硫化氢环境下发生应力腐蚀开裂。介绍了检验方法和通过改善材料和防腐工艺避免开裂方法。     

SOME FACTORS INVOLVED IN THE PREHEATING OF GLASS POTS WITH SPECIAL REFERENCE TO MOISTURE CONTROL1

The moisture content of the atmosphere of a pot arch preheating covered pots is a very important factor. Heating in a humid atmosphere tends to equalize the rate of removal of moisture from the inside and the outside surface of the pot at temperatures above 212°, decreasing mechanical strains set up in this process.     

基于ANSYS的侧加热锌锅厚度选择与温度控制模拟

利用ANSYS热应力分析模块对侧加热锌锅均匀加热时的锅壁进行稳态热分析,得到应力等值线分布图,通过对产生热应力原因的分析,得出不同厚度下侧加热锌锅外侧壁在允许屈服应力强度下所能承受的最大加热温度。为热镀锌生产线上延长锌锅寿命提供理论依据,同时也为锌锅制造厂家选择锌锅厚度与铸造锌锅时选择焊接位置提供参考。     

Effect of oxidation and residual stress on mechanical properties of SiC seal coated C/SiC composite

The effect of oxidation and thermal residual stress on mechanical properties of SiC seal coated C/SiC composite at ambient temperature and high temperature were studied. The oxidation of SiC seal coated C/SiC composite at 1300 and 1500 °C resulted in carbon fibres burn area near through thickness micro cracks in the SiC seal coating. With the increase in exposure time, the formation of SiO₂ layer in SiC matrix near carbon fibres burns area was found. Residual mechanical properties of SiC seal coated C/SiC composite after exposure in air show significant degradation. First time, a continuous measurement of Young's modulus with temperature of C/SiC composite was carried out using an impulse excitation technique. The effect of relaxation of thermal residual stress on mechanical properties was observed with the help of continuous measurement of Young's modulus as a function of temperature in an inert atmosphere.     

加氢反应器裙座支撑区的机械应力分析

加氢反应器是石油产品加工的重要设备,由于其工作在高温高压的场合下,机械应力很大,所以对其裙座支撑区的机械应力分析就尤为重要,在设计时不应忽略.利用ANSYS软件建立了加氢反应器裙座支撑区有限元模型,并对其进行机械应力分析.     

高聚物黏结炸药的力学性能研究进展

从材料的力学行为特性、实验方法、本构模型和强度理论4个方面对高聚物黏结炸药(PBX)的力学性能特征进行了归纳和评述。指出应变率和温度对材料应力状况的影响及动态力学性能分析是目前PBX研究的热点和难点。认为可以借鉴研究混凝土和高聚物的一些方法来建立PBX的本构模型和失效准则。指出选择和改进现有测试技术时,须考虑PBX的含能敏感性、大变形等特性。对PBX力学性能的理论研究、实验技术及数值模拟等方面需要开展的工作提出了一些看法。认为复杂环境下的力学响应和细观建模模拟应是今后研究的重点方向。附参考文献93篇。     

Kinetics of property change associated with atmospheric humidity changes in alumina powder granules with PVA binder

A microcompression testing machine was used on single Al₂O₃ powder granules to study their stress–strain behavior as a function of relative humidity. The test granules were prepared by spray-drying slurries containing 3 mass% poly(vinyl alcohol) and Al₂O₃ powder. The stress–strain curves and granule strength were determined at regular time intervals, after step changes in atmospheric humidity. When stress was applied, deformation increased rapidly with the stress. This stress corresponded to the fracture strength of the granule. In a dry atmosphere, the granules deformed linearly with increasing stress, and a rapid change in strain was noted above a certain critical value of increased stress. In a wet atmosphere, the granules deformed continuously at lower stress. The mechanical properties of the granules changed rapidly with time when the atmospheric relative humidity was changed. Within 3 min of exposure to a new atmosphere, the mechanical properties of the granules reached equilibrium values. The change in properties with humidity was controlled by moisture diffusion in the granules and was reversible.     

Mechanical Degradation of MgO by Water Vapor

The effect of exposure to the laboratory atmosphere on the fracture stress and Young's modulus of poly crystalline magnesium oxide was studied. The observed degradation of mechanical properties was attributed to chemical attack by atmospheric water vapor. The rate and extent of degradation depended on the amount and nature of porosity in the specimens.     

Investigation of mechanical behavior of CPC/bone specimens by finite element analysis

Calcium phosphate cement (CPC), as an important injectable biomaterial, is extensively used for bone repair in clinical application. If mechanical properties of CPC match well with that of bone tissue, it can create an appropriate mechanical environment for bone repair. In our study, the objective was to investigate the responses of bone tissue to CPC in different series of elastic modulus combinations. Finite element analysis (FEA) was applied to calculate the stress/strain on CPC-bone specimens and to further forecast the potential risky area. The predicted results indicated that CPC materials and bone tissue had different stress distribution patterns under the same loading condition. For CPC material, the Von Mises Stress peak occurred in the bone–cement joint area; while for bone tissue, the risky area was located at the bridge area among trabecular bones. The porous and loose structure of cancellous bone induced a greater Von Mises Stress in bone tissue. Quantitative analysis indicated that stress/strain distribution was directly correlated with the elastic modulus of material. When Young's modulus of bone and CPC was 1 GPa and 6.10 GPa respectively, the optimal stress matching between bone and CPC was achieved. In sum, this work confirmed that FE modeling was the ideal method for predicting fracture behavior of bone–CPC specimen both qualitatively and quantitatively.     

Grain size effects on the electric and mechanical properties of submicro BaTiO3 ceramics

In this study, a group of submicro BaTiO₃ ceramics ranging from 330 nm to 1.05 μm was successfully prepared by a two-step sintering process and the dependence of electric and mechanical properties on grain size was investigated. By dynamic mechanical analysis (DMA), phase transitions and grain size effects on modulus and internal friction were clearly detected. A clear low-frequency relaxation behavior induced by Debye relaxation was characterized in orthorhombic phase for fine BT ceramics. Furthermore, Arrhenius relationship was applied to theoretically analyze the relaxation peak, for which 90° domain wall motion was considered to be responsible. Another anomaly peak around 70 °C became more obvious after annealing in oxygen atmosphere, which was caused by the surface charge release, the interaction between domain walls and stress, and size effect.     

基于三维地应力场反演的冲击危险区域评价研究

为了提高矿井冲击危险区域评价精度,基于三维地应力场反演技术开展了相关研究。以集贤煤矿9号煤层西二采区为研究对象,在地质构造特征分析、煤岩物理力学性质和矿井地应力实测的基础上,根据多元线性回归原理对三维地应力场进行数值模拟反演,获得了研究区域内三维地应力场的相关信息,在综合考虑构造应力和采动应力影响的情况下,实现了对9号煤层西二采区冲击危险的宏观评价和对局部范围内冲击危险的精确评价,指导矿井的安全生产。