Design and Sealing Performance Verification of Graphite Seal Assembly of CRDM
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摘要: 控制棒驱动机构(CRDM)检修及堆芯换料时都需要多次拆卸CRDM的耐压壳体,为解决现有耐压壳体Ω密封焊缝泄漏以及不能多次拆卸的问题,本文采用螺母压紧石墨环方案,利用石墨环的压缩回弹性能防止冷却剂泄漏,并设计一种石墨环密封组件实现快速拆卸;通过开展密封环压缩回弹测试、应力松弛测试以及密封组件泄漏率等密封性能测试试验对石墨环密封组件的密封性能进行验证。结果表明,本文设计的石墨环密封环组件满足设计要求,可以实现高温高压环境下的密封性能。
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关键词:
- 控制棒驱动机构(CRDM) /
- 可拆式密封结构 /
- 石墨环 /
- 石墨环密封组件 /
- 密封性能试验
Abstract: The pressure housing of CRDM needs to be disassembled many times during the maintenance of control rod drive mechanism (CRDM) and core refueling. In order to solve the leakage of Ω sealing weld of the existing pressure housing and the problem that it can not be disassembled many times, the scheme of pressing graphite ring with nut is adopted in this paper, the compression resilience of graphite ring is used to prevent coolant leakage, and a kind of graphite ring sealing assembly is designed to realize rapid disassembly. The sealing performance of graphite ring sealing assembly is verified by carrying out sealing performance tests such as compression rebound test of sealing ring, stress relaxation test and leakage rate of sealing assembly. The results show that the graphite ring sealing ring assembly designed in this paper meets the design requirements and can achieve sealing performance under high temperature and high pressure environment. -
表 1 石墨环性能指标
Table 1. Performance Index of Graphite Ring
参数 指标值 压缩率/% 10~25 回弹率/% ≥35 应力松弛率/% <10 泄漏率/(Pa·m3·s−1) 1×106 表 2 石墨环压缩率及回弹率试验数据
Table 2. Test Data of Compression Ratio and Rebound Rate of Graphite Ring
石墨环类型 石墨环厚/mm 压缩量/mm 回弹量/mm 压缩率/% 回弹率/% 内圈石墨环1 5.59 0.91 0.40 16.28 56.04 内圈石墨环2 5.58 0.93 0.41 16.67 55.91 外圈石墨环1 5.60 0.96 0.47 17.14 51.04 外圈石墨环2 5.59 0.99 0.57 17.71 42.42 表 3 泄漏率试验结果
Table 3. Leakage Rate Test Results
测试参数 第一组 第二组 第三组 I0/(10−8 Pa·m3·s−1) 3.50 3.35 2.10 I1/(10−8 Pa·m3·s−1) 4.94 5.00 3.73 反应时间/s 34 35 34 Qs/(10−8 Pa·m3·s−1) 1.32 1.32 2.60 γ/% 16 13 15 n倍反应时间/s 102 105 102 I2/(10−8 Pa·m3·s−1) 3.89 3.57 2.60 Q/(10−8 Pa·m3·s−1) 2.68 1.35 3.15 -
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