Research on Full-Cover Fixed Ultrasonic Inspection Technology for AP1000 Control Rod
-
摘要: 控制棒组件是燃料组件中控制堆芯反应性的部件，因此需要及时对其状态进行评估，以确保核电站运行安全。本文针对AP1000控制棒结构、尺寸，研究了全覆盖式固定超声检查技术，并开发了专用检查装置。经过缺陷模拟棒的测试可知，本技术的缺陷轴向测量精度≤1 mm，壁厚测量精度<0.01 mm。本装置已成功应用于AP1000机组现场大修中，且发现了若干磨损缺陷和肿胀缺陷。应用结果表明，全覆盖式固定超声检查技术可对控制棒包壳的缺陷进行直观显示，并给出缺陷的位置、轴向长度、周向跨度、最大磨损深度等信息。Abstract: The control rod assembly is the component inserted into the fuel assembly to control the reactivity of the reactor core, so its status needs to be evaluated timely to ensure the safety of the plant operation. According to the structure and size of AP1000 control rod, the full-cover fixed ultrasonic inspection technology is studied in this paper, and the special inspection device is developed. Through the test of the mock-up flaw rod, it is known that the axial measurement accuracy of the flaw is ≤1 mm and the wall thickness measurement accuracy is <0.01 mm. The device has been successfully applied in the field overhaul of AP1000 unit, and several wear and swelling defects have been found. The application results show that the full-cover fixed ultrasonic inspection technology can visually display the defects of the control rod cladding, and give information such as the position, axial length, circumferential span and maximum wear depth of the defects.
-
Key words:
- Control rod /
- Fixed ultrasonic inspection technology /
- Full-cover
-
图 2 固定超声检查方法原理示意图
S—探头与包壳外壁间距离的理论值；S1、S2—探头与包壳外壁间距离的测量值
Figure 2. Schematic Diagram of Fixed Ultrasonic Inspection Method
表 1 控制棒尺寸
Table 1. Size of Control Rod
类型 长度/mm 包壳外径/mm 包壳厚度/mm 黑棒 4496.8 9.677 0.470 灰棒 4496.8 9.677 0.648 
下载: 导出CSV
表 2 模拟缺陷类型和尺寸
Table 2. Types and Sizes of Simulated Defects
缺陷编号 A B C 缺陷类型 环槽 环槽 轴向裂纹 深度/% 20 50 20 长度/mm 20 20 12.7 深度—壁厚损失的百分比
下载: 导出CSV
表 3 缺陷模拟棒检查结果
Table 3. Test Results of Rods with Simulated Defects
检查次序 A1 A2 A3 B1 B2 B3 最小轴向位置/mm 411 412 411 342 342 342 最大轴向位置/mm 430 432 430 361 362 361 轴向长度/mm 19 20 19 19 20 19 轴向误差/mm 1 0 1 1 0 1 剩余壁厚/mm 0.38 0.38 0.37 0.24 0.24 0.24 磨损百分比/% 19.15 19.15 21.28 48.94 48.94 48.94 壁厚误差/mm 0.004 0.004 0.006 0.005 0.005 0.005 A1~A3—缺陷A扫查3次的结果；B1~B3—缺陷B扫查3次的结果
下载: 导出CSV
-
[1] 周红,肖志,陶书生,等. 运行核电厂控制棒组件及其驱动机构异常事件的经验反馈[J]. 核安全,2013(1): 19-22, 35. doi: 10.3969/j.issn.1672-5360.2013.01.005 [2] MATSUOKA T, YAMAGUCHI Y, YONEZAWA T, et al. Cladding tube cracking caused by absorber swelling for PWR RCCA rodlets[J]. Journal of Nuclear Science and Technology, 1999, 36(7): 584-595. doi: 10.1080/18811248.1999.9726242 [3] 陈军. 田湾核电站控制棒组件检测系统科研项目风险管理[D]. 长春: 吉林大学,2011. [4] 蔡家藩,陈增武,乔维,等. 核电站反应堆控制棒束组件自动检查[J]. 无损检测,2013, 35(5): 71-74, 77. -
计量
- 文章访问数: 93
- HTML全文浏览量: 26
- PDF下载量: 43
- 被引次数: 0
