共查询到19条相似文献,搜索用时 125 毫秒
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燃料棒真空电子束焊机能对两种规格的燃料棒进行环焊,其一次性装料量大,焊接速度快,自动化程度高;本文对设备(机械部分)的结构和工作过程作了详细介绍,对设备的主要部件和系统进行了分析和研究。 相似文献
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针对辐照后燃料棒棒间距数据获取和处理困难的问题,基于燃料棒几何特性及其在压水堆燃料组件中的排列方式,本文提出一种基于机器视觉的高效、可靠的燃料棒棒间距数据测量方法。该方法首先采用Retinex算法对水下燃料棒的采集图像进行增强预处理;然后,针对燃料棒阵列的前后成像干扰问题,采取边缘增强和逐行灰度特征处理方法实现待测燃料棒与背景燃料棒的有效分离,并进一步提升图像清晰度;最后,对燃料棒图像的单行灰度值进行二次曲线拟合,获得各个燃料棒的亚像素边缘点坐标。乏燃料组件的现场实验验证结果表明,该方法可一次性实现16个燃料棒棒间距测量,且测量精度达±0.32 mm,可为燃料性能分析提供高效、可靠的数据支持。 相似文献
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在核电厂正常运行过程中,由于一回路杂物的存在或燃料操作失误,出现了少量燃料棒损伤的情况,通过采用哑棒替换损伤燃料棒可修复损伤燃料组件并回堆使用,可避免降低核电厂运行经济性。本文通过模拟采用不锈钢和锆合金哑棒替换破损燃料棒对燃料组件进行修复,分析修复后燃料组件中子学特性及修复燃料组件对堆芯运行核特性参数的影响机理,评估采用哑棒修复燃料组件并回堆使用对堆芯运行安全的影响,对采用哑棒修复燃料组件建立了完整的核设计分析方法和流程。该方法对采用哑棒修复燃料组件的核设计分析具有广泛的适用性,对采用修复燃料组件的堆芯换料设计具有实际的指导意义。该分析方法和流程的建立在国内反应堆物理分析领域尚属首次,目前该技术已应用于恰希玛一期核电厂堆芯换料设计的工程实践。 相似文献
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破损燃料组件修复后再次入堆使用是必须进行安全评估,以确保核安全。本文以采用AFA3G燃料组件的CPR1000机组为研究对象,对装入反应堆后的正常燃料组件和修复燃料组件的核物理和功率分布进行分析评估。结果表明:燃料组件内更换一根燃料棒对燃料组件反应性的影响很小,该影响可以忽略。更换不锈钢棒的数量越大,燃料组件反应性变化幅度越大。随着燃耗的加深,燃料组件反应性变化幅度也增大。修复的燃料组件虽然在换棒位置局部区域发生功率畸变,相对功率略微的升高,但离换棒位置较远的燃料棒的相对功率没有变化,换棒不会导致组件内功率峰发生象限的偏移。 相似文献
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欧美等国在燃料棒制造中大都采用TIG法,而我国则采用了电子束焊接方法。电子束焊是一种在高真空中进行的机械熔化焊方法,特别适用于燃料棒的焊接。目前生产中使用了两种专用真空电子束焊机。ES1-2型焊机,它采用自动焊接夹具,在真空中完成上料—焊接—冷却—下料,每次100根。HD-60型焊机,它仅将焊接处局部密封在真空室中,该机的动作和参数均由计算机控制。燃料棒电子束焊接中出现的成形差是由电子束焦点畸变,飞溅,灯丝老化等造成,采用对中电子枪,电子束扫描,选择合理规范来解决;未焊透是由焦点功率密度变化所致,采用调整焦点大小及位置,或改进接头结构,提高加速电压来消除;气孔产生的原因较特殊,可能是飞溅,表面清洁度,配合间隙中残留气体等引起,一般采用严格清洗工件,电子束扫描或改进端塞结构等措施来避免。 相似文献
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欧美等国在燃料棒制造中大都采用TIG法,而我国则采用了电子束焊接方法。电子束焊是一种在高真空中进行的机械熔化焊方法,特别适用于燃料棒的焊接。目前生产中使用了两种专用真空电子束焊机。ES1-2型焊机,它采用自动焊接夹具,在真空中完成上料—焊接—冷却—下料,每次100根。HD-60型焊机,它仅将焊接处局部密封在真空室中,该机的动作和参数均由计算机控制。燃料棒电子束焊接中出现的成形差是由电子束焦点畸变,飞溅,灯丝老化等造成,采用对中电子枪,电子束扫描,选择合理规范来解决;未焊透是由焦点功率密度变化所致,采用调整焦点大小及位置,或改进接头结构,提高加速电压来消除;气孔产生的原因较特殊,可能是飞溅,表面清洁度,配合间隙中残留气体等引起,一般采用严格清洗工件,电子束扫描或改进端塞结构等措施来避免。 相似文献
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脉冲堆燃料元件表面温度测量用的铠装热电偶,其端头部分的套管外径仅为0.25mm。通过对焊接形式、封头工艺及热电偶与燃料元件表面的焊接工艺进行研究比较,采用了脉冲氩弧焊封头、激光点焊焊接的方法。对焊后模拟件进行的各种检验表明,所采用的方法是可行的。 相似文献
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Jong-Youl Park Tae-Hyung Na Tae-Hyuk Lee Bo-Young Lee Jae-Sung Kim 《Journal of Nuclear Science and Technology》2013,50(5):748-757
The welding of zirconium alloy components is one of the most critical processes in the fabrication of nuclear fuel rods used in pressurized water reactors. For this, various welding processes, such as gas tungsten arc welding, electron beam welding, laser beam welding, and resistance pressure welding (RPW), are used around the world. In Korea, the RPW process is being used to fabricate nuclear fuel assembly fuel rods. This study investigated changes in the weldment shape owing to welding conditions such as welding current, welding force, and overlapping. The welding soundness of the weldment was evaluated by hydraulic burst test. The welding temperature of the weld zone was measured using a thermal infrared method. Discontinuous black spots in the weld line, regarded as a non-bonding defect, were confirmed as spots caused by the carbide precipitation of zirconium during welding. 相似文献
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S. V. Pavlov 《Atomic Energy》2011,110(4):241-247
The effect of fuel burnup in VVER-1000 fuel elements on the utilization effectiveness of ultrasonic detection of leaky fuel
elements is examined. It is determined that the limitations of this method are due to the interaction of fuel-element cladding
with the fuel pellets. Threshold for fuel burnup in VVER-1000 fuel elements with E-110 alloy cladding, determining the application
limits of ultrasonic detection of leaky fuel elements in fuel assemblies, is determined. 相似文献
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I. I. Fedik S. S. Gavrilin V. P. Deniskin V. I. Nalivaev V. S. Konstantinov N. N. Ponomarev-Stepnoi N. E. Kukharkin I. I. Konovalov Yu. G. Dragunov S. B. Ryzhov V. P. Spasskov V. I. Subbotin 《Atomic Energy》2004,96(4):250-259
The results of development work on a new generation of fuel elements based on microfuel for VVÉR reactors using the basic data from post-reactor investigations and bench tests in experiments simulating LOCA for existing fuel elements with ceramic fuel are presented. It is shown that cermet fuel elements will make it possible to realize most fully the advantages of such fuel, specifically, to develop a sealed first loop and to simplify and reduce the cost of safety, automatic control, radiation protection, coolant puification, and other systems. For example, cermet fuel elements in VVÉR-1500 reactors can improve safety under various operating conditions, maneuverability, vibrational strength, fuel assembly lifetime, and geometric stability of fuel elements. 相似文献
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A. V. Vatulin A. V. Morozov V. B. Suprun Yu. I. Petrov Yu. I. Trifonov 《Atomic Energy》2006,100(1):37-46
The results of radiation tests are discussed and the character of the failure of fuel compositions and the operability of
fuel elements is analyzed as a function of the type of fuel and the irradiation conditions. The intense interaction of the
fuel with the matrix material is considered as the main factor limiting the operability of fuel elements in power-dense high-flux
nuclear reasearch reactors. It is concluded that low-enrichment high-density uranium—molybdenym fuel can provide reliable
operation of dispersion fuel elements in low-and medium-power research reactors. Such fuel can be used in power-dense high-flux
research reactors if the fuel load is decreased below the maximum admissible amount, the compatibility of the uranium—molybdenum
alloy with an aluminum matrix is radically improved, or fuel elements with a different construction, for example, monolithic,
are used.
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Translated from Atomnaya énergiya, Vol. 100, No. 1, pp. 35–44, January, 2005. 相似文献
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A. I. Bobylev S. N. Elsukov S. I. Rovnyi A. V. Ryakov I. A. Shkabura V. A. Astaf'ev 《Atomic Energy》2003,95(4):715-719
The results of fabrication of fuel elements with mixed uranium–plutonium oxide fuel are presented. The experimental fuel assemblies assembled from the fuel elements were tested in BN-350 and -600 reactors. Postreactor investigations of the fuel elements showed that there was no substantial difference in the behavior of the fuel cores consisting of the mixed fuel as compared with UO2 fuel. Solid and liquid radioactive wastes are produced during the fuel fabrication process. A classification of the wastes and methods for handling them is given. It is shown that the off-grade sintered pellets should be pulverized and returned to the beginning of the mixed-fuel fabrication process. 相似文献