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石油钻柱无损探伤检测技术现状和展望 总被引:2,自引:0,他引:2
简述了石油钻柱无损探伤检测的必要性和重要性,较系统地介绍了钻柱无损探伤技术方法、标准、仪器设备和检测现状,叙述了钻柱无损探伤检测技术进一步发展的前景。提出了几点预防和减少钻柱事故的无损探伤检测措施。 相似文献
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无损探伤技术无损探伤技术作为检验产品质量、降低成本的重要手段之一,其范围包括有:目视,渗透,腐蚀,射线,磁力,压力,超声,挽救等八种,前四种方法在轻合金生产中已得到广泛应用,几乎所有车间、库房、试验室都有无损探伤设备,几乎所有零件工程图纸都有要求无损探伤检查裂纹,对大而复杂的铸件在热处理前后要作几次无损探伤,对补焊区域则要进行100%无损探伤。其方法有目视、腐蚀、渗透、射线检查等,随着非磁性材料在宇航中越来越多地 相似文献
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在分析影响无损探伤结果可靠性的众多因素的基础上,阐述发定量评估无损探伤能力的Bayes方法,分析了误检参数和结构质量参数对探伤物影响程度,并对有关检测结果作了定量评估,指明了提高无损探伤能力的主要途径。 相似文献
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The principle of the stretch reducing process is analyzed and three models of pass design areestablished. The simulations are done about variables, such as, stress, strain, the stretches betweenthe stands, the size parameters of the steel tube, and the roll force parameters. According to itsproduct catalogs the system can automatically divide the pass series, formulate the rolling table,and simulate the basic technological parameters in the stretch reducing process. All modules areintegrated based on the developing environment of VB6. The system can draw simulation curvesand pass pictures. Three kinds of database including the material database, pass design database,and product database are devised using Microsoft Access, which can be directly edited, corrected,and searched. 相似文献
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随着北极航行的发展及极地资源开发的需要,如何提高极地海洋环境服役材料的摩擦学性能愈发重要。在极地海洋环境中,碎冰、冰层和海水中的腐蚀性物质会使材料受到摩擦磨损、腐蚀及其耦合的影响;低温潮湿环境会增加材料的脆性、使材料表面覆冰、改变材料的摩擦磨损机理;强紫外线会加速涂层老化;这些因素都会降低材料的耐磨性能,最终导致材料失效。因此,极地海洋环境服役材料的摩擦学与材料的性能、服役寿命息息相关。本文介绍了极地探索所面临的摩擦磨损问题;阐述了极地温度、极地海洋大气及海水成分、海冰运动和极地微生物等极地海洋环境特点及其对材料摩擦学性能的影响;重点介绍了金属材料、无机非金属材料、高分子材料在极地海洋环境下的摩擦学进展;探讨了提升材料在极地海洋环境下的耐磨防腐技术,如改性、表面修饰等;最后,结合极地海洋环境服役材料摩擦磨损研究中所面临的问题及发展趋势,对未来极地海洋服役材料的摩擦学研究工作进行展望。 相似文献
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Carl Christoph Stahr Sabine Saaro Lutz-Michael Berger Jiri Dubský Karel Neufuss Mathias Herrmann 《Journal of Thermal Spray Technology》2007,16(5-6):822-830
A phase change from α-alumina (corundum) in the feedstock powder to predominantly other alumina phases, such as γ-alumina
in the coating normally takes place, as a result of the spray process. It is expected that the prevention of this phase transformation
will significantly improve the mechanical, electrical, and other properties of thermally sprayed alumina coatings. The results
regarding the possibility of stabilization of α-alumina through addition of chromia published in the literature are ambiguous.
In this work, stabilization using different spray processes (water-stabilized plasma (WSP), gas-stabilized plasma (APS), and
high-velocity oxy-fuel spray (HVOF)) was studied. Mechanical mixtures of alumina and chromia were used, as were prealloyed
powders consisting of solid solutions. The investigations focused on mechanical mixtures with both APS and WSP and on prealloyed
powders with WSP. The coatings were studied by x-ray diffraction, including Rietveld analysis, and analysis of the lattice
parameters. Microstructures were investigated by optical microscopy using metallographic cross-sections. It was shown that
in the case of the mechanically mixed powders, the stabilization predominantly depends on the applied spray process. The stabilization
of the α phase by use of the WSP process starting from mechanical mixtures was confirmed. It appears that stabilization exhibits
a complex dependence on the spray process, the process parameters (in particular the thermal history), the nature of the powder
(mechanically mixed or prealloyed), and the chromia content.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
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G.H. Liu G.S. Ren C.G. Xu 《金属学报(英文版)》2007,20(5):380-384
Basing on the analysis of the traits of the roll forging process, a system-model of computer simulation has been established. Three-dimensional rigid-plastic FEM has been used for the simulation of the deformation process in the oval and round pass rolling, including the entering, rolling, and separating stages. The analysis was conducted using the Deform-3D ver.5.0 code. The important information concerned with the deformation area characteristic, material flow, and velocity field has been presented. Otherwise,the location of the neutral plane in the deformation area was shown clearly. 相似文献
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M.-F. Zhu W. Cao S.-L. Chen C.-P. Hong Y. A. Chang 《Journal of Phase Equilibria and Diffusion》2007,28(1):130-138
Driven by industrial demand, extensive efforts have been made to investigate microstructure evolution and microsegregation
development during solidification of multicomponent alloys. This paper briefly reviews the recent progress in modeling of
microstructures and microsegregation in solidification of multicomponent alloys using various models including micromodel,
phase field, front tracking, and cellular automaton approaches. A two-dimensional modified cellular automaton (MCA) model
coupled with phase diagram software PanEngine is presented for the prediction of microstructures and microsegregation in the
solidification of ternary alloys. The model adopts MCA technique to simulate dendritic growth. The thermodynamic data needed
for determining the dynamics of dendritic growth are calculated with PanEngine. After validating the model by comparing the
simulated values with the prediction of the Scheil model for solute profiles in the primary dendrites as a function of solid
fraction, the model was applied to simulate the microstructure and microsegregation in the solidification of Al-rich ternary
alloys. The simulation results demonstrate the capabilities of the present model not only to simulate realistic dendrite morphologies,
but also to predict quantitatively the microsegregation profiles in the solidification of multi-component alloys.
This article was presented at the Multi-Component Alloy Thermodynamics Symposium sponsored by the Alloy Phase Committee of
the joint EMPMD/SMD of The Minerals, Metals, and Materials Society (TMS), held in San Antonio, Texas, March 12-16, 2006, to
honor the 2006 William Hume-Rothery Award recipient, Professor W. Alan Oates of the University of Salford, UK. The symposium
was organized by Y. Austin Chang of the University of Wisconsin, Madison, WI, Patrice Turchi of the Lawrence Livermore National
Laboratory, Livermore, CA, and Rainer Schmid-Fetzer of the Technische Universitat Clausthal, Clauthal-Zellerfeld, Germany. 相似文献
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Georg Mauer José-Luis Marqués-López Robert Vaßen Detlev Stöver 《Journal of Thermal Spray Technology》2007,16(5-6):933-939
Wear at the electrode surfaces of a one-cathode plasma torch changes the characteristic fluctuation pattern of the plasma
jet. This affects the trajectory of the particles injected into the plasma jet in a non-controllable way, which degrades the
reproducibility of the process. Time-based voltage measurements and Fourier analysis were carried out on a one-cathode F4
torch at different wear conditions to determine the evolution of wear dependant characteristics. A significant correlation
is observed between increasing torch wear and decreasing voltage roughness and high frequency noise. Furthermore, by means
of particle diagnostic systems, the change in the particle velocity and temperature has been measured. The variations of the
particle characteristics are significant and thus an influence on the sprayed coating microstructure is to be expected.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
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通过激光合金化技术在45钢基体上制备Mo1B9Crx合金化涂层,研究了Cr含量对涂层组织性能的影响。结果表明,Mo1B9Cr1.1涂层最佳激光合金化工艺为激光功率3.3 kW,扫描速度900 mm/min,搭接率30%;在此工艺条件下,涂层与基体呈良好的冶金结合,无孔洞和裂纹,合金化区组织为Fe-Mo、Fe2B、Fe-Cr、Cr2B、CrxFey固溶体和化合物;随Cr含量从1.1%增加到23.3%,涂层硬度、摩擦因数、磨损率逐渐减小;当Cr含量为1.1%时,涂层硬度最大,为1005 HV0.1;当Cr含量为23.3%时,其耐磨性能最好,摩擦因数为0.475,磨损率为0.574×10-14m3/(N·m),涂层磨损形式主要是磨粒磨损和粘着磨损结合的形式。 相似文献
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Z. Sun S.L. Zheng Y. Zhang 《金属学报(英文版)》2007,20(3):187-192
Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process. 相似文献
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Recently, there has been a rapid development in computer technology, which has in turn led to develop the fully robotic welding system using artificial intelligence (AI) technology. However, the robotic welding system has not been achieved due to difficulties of the mathematical model and sensor technologies. The possibilities of the fuzzy regression method to predict the bead geometry, such as bead width, bead height, bead penetration and bead area in the robotic GMA (gas metal arc) welding process is presented. The approach, a well-known method to deal with the problems with a high degree of fuzziness, is used to build the relationship between four process variables and the four quality characteristics, respectively. Using these models, the proper prediction of the process variables for obtaining the optimal bead geometry can be determined. 相似文献
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针对卡箍模具冲压成形后,成形件因弹性变形消失而发生回弹的问题,利用ABAQUS对模具成形过程进行数值模拟,研究卡箍模具表面不同摩擦特性的分布对成形件回弹的影响。首先根据卡箍模具的特征结构对卡箍模具表面进行区域划分,并以卡箍成形件的回弹量为优化目标。采用单因素与均匀设计相结合的方法,确定当卡箍模具表面的最佳摩擦特性分布为:μ5=0. 12,μ6=0. 13,μ7=0. 14,μ9=0. 16,μ10=0. 18,μf=0. 11,其他区域摩擦系数为0. 12,此时卡箍成形件的回弹量最小。并在数值模拟的基础上进行试验验证,试验结果表明卡箍成形件的回弹得到了改善。 相似文献