核电厂BOSS焊缝在线堆焊修复相控阵超声检验技术

核电厂反应堆换料水池与乏燃料水池冷却和处理系统（PTR）及设备循环冷却系统（RRI）中含有大量管座接头（BOSS）焊缝,其安全性和可靠性直接影响所存储核燃料的安全状态,对其进行缺陷排查和在线修复是核电厂在役检查监督的重点和难点。本文针对BOSS焊缝在线堆焊修复的特殊要求和检验难点以及射线检验的局限性,设计了一套专用的相控阵超声探头和检验工艺,试验验证结果满足堆焊修复要求,并制订了核电厂BOSS焊缝堆焊修复无损检验的方法和在役检查监督的策略。     

EPR核电厂CRDM耐压壳焊缝缺陷信号分析

核电厂控制棒驱动机构（CRDM）长期处于高温、高压和高辐射环境中,其耐压壳异种金属焊缝容易出现裂纹等缺陷,是大修期间在役检查的关注重点。针对该焊缝役前超声检查中发现的疑似缺陷显示,通过补充目视、射线、超声相控阵和破坏性试验,验证了此类显示信号为不完全再结晶的奥氏体硬化晶粒造成的冶金显示,不影响耐压壳焊缝的质量,并总结了核电厂核岛设备超声疑似缺陷信号分析验证的方法。      

核电厂CRDM耐压壳焊缝超声检验工艺设计

控制棒驱动机构（CRDM）耐压壳属于核电厂主回路,其连接焊缝是整个放射性回路压力边界的薄弱环节,其安全性和可靠性直接影响反应堆的安全运行状态。针对CRDM耐压壳焊缝附近空间狭小、壁厚薄、可达性差等特点,本文采用仿真技术设计了一套专用的扁平型双晶聚焦超声探头和检验工艺,试验验证结果满足规程要求,解决了核电厂在役检查的监督难点,并获得了核电厂主回路Ⅰ级部件类似焊缝检验的工艺设计和验证方法。      

快堆P91钢主蒸汽管道焊缝超声相控阵检测工艺研究

快堆的主蒸汽管道使用P91钢材料,与压水堆主蒸汽管道的材料不同。通过对P91钢的声学特点、主蒸汽管道及焊缝的结构、可能存在的焊缝缺陷类型和分布位置进行分析,使用超声相控阵仿真软件进行声线覆盖仿真模拟,设计了P91钢主蒸汽管道焊缝超声相控阵检测的工艺流程。设计并制作了模拟试块对超声相控阵检测工艺参数进行验证,验证结果表明,设计的超声相控阵检测工艺流程对不同类型、尺寸、方向和位置的缺陷有较高的检出率,可以满足现场实际需求。     

核电站关键部件在役检查可靠性分析

基于可靠性概率统计模型和超声检测数值模型,对在役检查的可靠性进行计算与分析.以核电厂反应堆压力容器环焊缝超声检测为例,计算不同检测参数下环焊缝中裂纹类缺陷及横孔的检出率曲线和95％置信下限.结果表明,可靠性分析方法的引入可以实现在役检查工艺方法及结果的定量评估.     

核岛安装管道对接环焊缝的检测方法

介绍了X射线技术和超声波技术在核岛管道对接环焊缝检测中的应用。优势和适用范围对比分析表明这两种方法能够有效地检测环焊缝缺陷。随后对全自动相控阵超声波检测技术的原理、特点和应用及射线检测的发展趋势进行了分析,全自动相控阵超声波检测技术和机器人检测技术不久将会在核岛管道安装乃至核电服务市场的质量控制上得到应用。     

核电厂阀杆超声相控阵检测技术

某核电厂1117-600-Э-M3型阀门阀杆出现过2次阀杆越程槽断裂事件。为防止此类事件再次发生,影响核电机组安全稳定运行,有必要对同类型阀门进行全面检查,查找缺陷。该类型阀门体积庞大,解体检查工作量大,针对该类型阀门和阀杆的结构特点开发专用超声波相控阵检测工艺,并于大修期间对同类型阀门阀杆实施检查。检查结果表明,超声相控阵检测技术可以实现对阀杆断裂敏感部位的有效检测,同时大大减少阀门解体所需要的人力物力。     

反应堆压力容器入口接管焊缝超声不可达区域非线性研究

压水反应堆压力容器入口(Inlet)接管与筒体对接焊缝具有复杂的几何体特征,且焊缝超声检查区域在多种在役检查规范中定义不一致,这些因素导致其不可达区域呈非线性变化。为研究该区域的特殊变化规律,建立了Inlet接管与筒体焊缝参数模型,分析坡面特征导致的不可达区域仿真方法和分类判别法则。基于该法则,结合美国机械工程师学会(ASME)规范与核电厂相关参数,运用三维仿真软件采集接管组件不可达区域体积离散数据集,求取出左、右不可达区体积占比-超声折射角关系图,并介绍占比指标在相控阵和常规超声工艺的应用和优化方法。本研究以减少不可达区域并提高缺陷发现概率为目的,特别适用于相控阵和常规超声工艺在此类焊缝的不可达性和分布规律的数理研究。     

国内在役核电厂首例电气贯穿件更换改造

核电厂电气贯穿件作为安全壳上的关键设备,承担着核岛内外各种电力和信号传输以及保证安全壳压力边界完整性的重要功能。通过秦山核电厂一期工程30万千瓦机组第18次大修期间国产在役DDG-1型电气贯穿件更换改造项目的实施,分析了秦山核电厂一期工程在役电气贯穿件设备现状和改造的必要性;针对在役核电厂更换改造工期短和贯穿件密封性能验证难等问题,通过优化检验工序、制作专用检漏工装的方法,缩短了贯穿件改造的工期并验证了贯穿件密封性能。     

M310核电机组BOSS焊缝作业辐射防护控制

BOSS焊缝为管道与支管管座的连接焊缝,核电厂放射性系统管道BOSS焊缝处进行分支与变径导致容易沉积高辐射水平粒子,另由于检修空间有限,其相关作业具有很高的辐射风险。文章结合BOSS焊缝作业主要步骤,分析了作业过程存在的外照射风险与放射性污染风险,并根据各辐射风险提出切实可行的辐射防护措施。作业过程中的经验反馈和实践,为M310核电机组BOSS焊缝作业的辐射防护控制提供参考。     

Steam generator small bore piping socket weld inspection using the phased array ultrasonic technique

As nuclear power plants age, the likelihood of failures in the small bore piping used in those plants caused by exposure to mechanical vibrations during plant operations increases. While small bore piping failures rarely cause plant shutdown, the management of small piping has been a keen area of interest since their repair or maintenance requires a reactor trip. Steam generator (SG) drain pipe socket welds are small diameter piping connections (nominal pipe schedule 3–4 inches) susceptible to mechanical vibration. SG drain pipe socket weld failures have caused coolant leakage. Therefore, more reliable inspection technologies for small bore piping need to be developed to detect problems at an early stage and prevent pipe failures. This research aims to improve the reliability and accuracy of small bore piping inspections through the design, manufacture and application of a new phased array ultrasonic testing technique and inspection system for SG drain line socket welds.     

New applications using phased array techniques

In general, the application of phased array techniques used to be limited to heavy components with large wall thicknesses, such as those in the nuclear power industry. With the improvement of the phased array equipment, including phased array search units, other application areas are now accessible for the phased array inspection technique, e.g. the inspection of turbine blade roots, weld inspection with a wall thickness ranging from 12 to 40 mm, inspection of aircraft components, inspection of spot welds and the inspection of concrete building components. The objective for the use of phased array techniques has not significantly changed since their first application, e.g. instant adjustment of the sound beam to the geometry of the test object by steering incidence angle, skew angle and/or sound field focusing. Because some new phased array technique applications are still in the experimental (laboratory) stage, this article will focus on some examples for practical, real-weld applications.     

Availability study of a phased array ultrasonic technique

A phased array ultrasonic testing method is expected to be applicable to nuclear power plants for electrical ultrasonic beam control and real time B-scope image display. The availability of the phased array ultrasonic technique has been investigated and it has been verified that the sound beam is electrically steered to the intended angle and is electrically focused at the intended position. From the results of experiments, the dynamic aperture sizing technique was established as a practical method and this technique was demonstrated for artificial flaws.     

关于核电站在役检查标准的探讨

基于我国核工业的发展和核电站的建设，指出了编制在役检查标准的重要性和可行性，从分析核电站在役检查的特点探讨了标准的基本内容。     

Development of an ultra sonic phased array system for nondestructive tests of nuclear power plant components

A phased array ultrasonic inspection (PAULI) system is being developed to obtain electronically scanned ultrasonic images of the inside of nuclear power plant components for nondestructive evaluation. The development strategy of PAULI system was the modification of a medical ultrasound imaging system that had 64 individual transceiver channels. Optimization of array transducers has been also pursued based on the systematic investigation of the radiation beam field simulated by the use of the boundary diffraction wave models. 7.5 MHz phased array transducers was, then, fabricated and tested with the carbon steel specimen having side-drilled holes. For the nondestructive tests on power plant component, a sample mockup of turbine blade root with EDM notches was fabricated and the detection capability was demonstrated. The developed system can provide electronically scanned ultrasonic images in real time fashion and greatly enhance the efficiency and reliability in the flaw detection and location in comparison with the classical ultrasonic testing (UT) using A-scan signals. For the flaw classification, the analysis of the electronically scanned ultrasonic images was not sufficient at this moment but analysis of features obtained from A-scan signals of flaws at the various steering angles showed the potential capability.     

Crack detection and sizing technique by ultrasonic and electromagnetic methods

Improvements in defect detection and sizing capabilities for non-destructive inspection techniques have been required in order to ensure the reliable operation and life extension of nuclear power plants. For the volumetric inspection, the phased array UT technique has superior capabilities for beam steering and focusing to objective regions, and real-time B-scan imaging without mechanical scanning. In contrast to the conventional UT method, high-speed inspection is realized by the unique feature of the phased array technique. A 256-channel array system has developed for the inspection of weldment of BWR internal components such as core shrouds. The TOFD crack sizing technique also can be applied using this system. For the surface inspection, potential drop techniques and eddy current techniques have been improved, which combined the theoretical analysis. These techniques have the crack sizing capability for surface breaking cracks to which UT method is difficult to apply. This paper provides the recent progress of these phased array and electromagnetic inspection techniques.     

压水堆核电厂核岛机械设备在役检查规则研究

压水堆核电厂核岛机械设备在役检查规则研究是修订和编制我国相关核电在役检查标准的基础和前提。本文简介了在役检查规则研究目标、方法、主要内容和结果以及在役检查规则制定依据,简述了规则研究相关主要问题的处理方法和结果,对比分析了依据研究结果编制的NB/T 20312标准与EJ/T 1041标准在役检查规则的主要不同点,给出了准确理解和正确应用NB/T 20312标准有关在役检查规则的提示和说明,为有效应用该标准在役检查规则提供重要参考。