摘要
对HL环流器系列装置,开发了蒽-丙酮荧光液渗透检漏用于真空内衬的零部件检漏,灵敏度可以达到10-9Pa.m 3.s-1,示漏位置分辨小于0.5mm;对大容器真空检漏,采用四极质谱计和氦质谱检漏仪相配合的检漏法;对压力容器检漏,开发了真空罩吸枪-氦质谱检漏系统,还研制了适于抽除大量水汽的检漏真空机组。对氘氚放电的JET,使用普通的氦质谱检漏仪(扇形磁体型)受到真空室壁释放所吸留的氢同位素的、尤其是氘的严重干扰,因为示漏气体氦(4H e,4.0026u)与氘(D2,4.0282u)的质量数十分相近。在氦质谱检漏仪入口处串接选择性抽气泵——用液氮冷阱来抽除可凝气体、用分子筛泵或10K低温泵来抑制氢同位素本底,并前置一个涡轮分子泵来压缩加强采样气流等。这种加强组合能使原先的氦质谱检漏系统灵敏度提高3个量级以上。
For HL tokamaks, a anthracene-acetone liquid fluorescent leak detection was developed for parts of liners,possessing a sensitivity of 10^-9 Pa·m^3·s^-1 and a leak position resolving power of a better than 0.5 mm; a QMS was cooperated with a helium leak detector for high vacuum leak detection; a sniffer with a vacuum cover-helium leak detector set was developed for pressured vessels detection and some vacuum pumping sets suitable for pumping huge water vapor were developed also. In JET with a D-T plasma, a conventional helium leak detector （sector magnet type） is suffered severely interference, because the first wails retained D particles release D2, and the released D2 （4.028 2 u） confuses the leaked ^4He（4.002 6 u） due to the near identical masses. A selective pumping set, including a liquid nitrogen cooled trap to pump all condensable gases and a getter pump or a 10 K cryopump to pump off hydrogen and its isotopes, is in series at the entrance of the helium leak detector, and a compression pump for exammple, a molecular drag pump or a compound molecular pump is placed in front of the pumping system to enhance the sampling gas flow through it. The enhancements have made it possible to detects leaks at least three orders of magnitude smaller than previously practical.
出处
《真空与低温》
2006年第2期63-67,共5页
Vacuum and Cryogenics
关键词
泄漏检测
选择性抽气机组
综述
压缩采样泵
四极质谱计
回旋质谱计
leak detection
selective pumping set
summarize
compression sampling pump
QMS
omegatron mass spectrometer
