大型原油储罐腐蚀的原因分析及防护对策

对大型外浮顶原油储罐发生腐蚀的原因进行了简要分析，针对原油储罐不同部位的腐蚀情况提出了防腐对策，特别指出在浮盘支柱底板上的对应处增焊不锈钢板，罐底板应采用涂料与阴极保护的联合保护。     

Structural integrity evaluation for corrosion in spherical pressure vessels

Corrosion is typical of the damage that occurs in ageing pressure vessels and pipelines used in industrial processes as a result of reactive products inside or harsh environmental conditions on the outside. Structural integrity of such components needs to be evaluated periodically to establish the continued suitability of the vessels under operating conditions. The present paper develops a method for Level 2 (as categorized by API 579) fitness-for-service (FFS) evaluation of spherical pressure vessels with localized corrosion. The decay lengths for spherical shells subject to different sizes of corroded areas are calculated based on elastic effects in shells so as to identify the reference volume participating in plastic action. Lower bound “remaining strength factors” of spherical pressure vessels containing corrosion damage are formulated by the application of Mura's variational formulation and the m-multiplier method. Three alternative design recommendations are given. The effectiveness of the proposed methods is evaluated and demonstrated through illustrative examples and comparison with Level 3 inelastic finite element analyses.     

Effect of Tank Size and Geometry on the Flow Induced by Circular Bubble Plumes and Water Jets

Ambient flow field and circulation patterns induced by circular bubble plumes and water jets in tanks of different sizes were studied in rectangular and square water tanks. A nonstationary nature of the flow was observed in all experiments and its dominant oscillation frequency was found to directly relate to the tank size. The flow circulation patterns were similar for bubble plumes and water jets, but changed significantly with tank size and geometry. Strong three-dimensional effects were observed in a rectangular tank, resulting in flow entraining in the longer plane and flow detraining in the shorter plane, especially for the bubble plume tests. A relationship was developed to relate the tank size to the patterns of circulation cells. Nearly isotropic turbulent flow conditions were obtained in all experiments, but the effect of tank size and geometry on the magnitude of the turbulent stresses was more pronounced in the bubble plume tests.     

Spherical dendritic particles formed in cavitation erosion

Micro spherical particles were found in a vibrating cavitation erosion experiment. Examination of the spherical particles reveals the dendritic pattern on the surface and the hollow structure of the interior. The surface and interior structures of the particle are also related to the particle’s size. For smaller particle, the dendritic structure is replaced by the fine cell and the interior becomes solid. Such special structures are considered to be the result of particle’s solidification from molten state at a rapid cooling rate, which happens in a special transient environment with transient high temperature and high pressure provided by cavity collapsing. The specific area and surface tension force are the main reasons for the different structures of the particles in different size.     

北盘江大桥12000t转体球铰的研制与应用

介绍了北盘江大桥用 12 0 0 0t转体球铰的材料研究、球铰制造、安装及转体运行。万吨荷载下 ,球铰以低于 0 .0 18的摩擦系数平稳转体 ,开创了大桥转体施工中应用填充聚四氟乙烯复合夹层滑板 /钢摩擦副球铰的先河。补充了万吨级球型桥梁支座模型试验数据 ,检验了万吨级球型桥梁支座摩擦副的可靠度     

Predictive power for life and residual life of the zinc rich primer coatings with electrical measurement

Zinc rich primers with lamellar and spherical shaped zinc pigments and their combinations were formulated. These zinc rich primers were used to measure the electrical conductance and subjected to the corrosion analysis for 3000 h. The lamellar shaped pigments at lower PVC were found to be better than spherical shaped pigments, whereas the typical combination of spherical and lamellar zinc was the best in providing corrosion protection. A set of equations were developed to predict the life and residual life for pigment of both shapes using PVC, conductance and corrosion resistance for 3000 h in salt spray as parameters. Finally the influence of zinc particle shape on the flow and orientation behavior was evaluated using rheological measurements.     

Surface modification of spherical magnesium oxide with ethylene glycol

The surface of spherical magnesium oxide has been modified with ethylene glycol in the presence of basic aqueous solution. Fourier transform infrared spectra have shown the presence of the graft group ethylene glycol on the surface of spherical magnesium oxide. In addition, this conclusion can also be drawn from appearance of new diffraction peak in X-ray diffraction pattern. Although magnesium oxide microspheres can directly react with ethylene glycol in 373 K for 24 h, owing to Lewis acid and alkali interaction, product derived is colloidal and difficult to filter so that their morphology is easy to be destroyed. However, in the presence of basic aqueous solution, their morphology still retains. The modified magnesium oxide illustrates a specific surface area of 55.9 m²/g and a narrow pore size distribution centered at 8.96 nm.     

大型原油储罐用钢的焊接热模拟试验

用焊接热模拟的试验方法研究了大型原油储罐用钢在大线能量焊接条件下焊接热影响区的冲击韧性，热模拟试验结果表明：大型原油储罐用钢在焊接线能量为100kJ／cm条件下，焊接热影响区的冲击韧性能够满足设计要求。     

Carbon dioxide capture with dolomite: A model for gas-solid reaction within the grains of a particulate sorbent

This work describes a mathematical model for a gas-solid reaction taking place within reactant particles made up of very small spherical grains, which grow during the reaction process due to solid product formation around the grain inner core, so that the particle void-fraction is reduced as the reaction proceeds. The structural changes in the spherical grains are taken into account in the proposed model by the inclusion of a variable diffusion coefficient of the gaseous reactant through the developing product layer. This progressively increasing transport resistance leads to a marked reduction in both reaction rate and sorbent capacity, as observed in practice in the carbonation of calcined dolomite, a process of importance in hydrogen production by means of coal or biomass gasification.     

10000m~3天然气球罐用WEL-TEN610CF钢焊接工艺试验研究

对37mm厚WEL-TEN610CF天然气球罐用钢的化学成分和力学性能进行分析,对其焊接性能进行了研究,制定出一套可行的焊接工艺,其焊接质量完全能够满足工艺规定及使用要求。