低温绝热容器氦质谱检漏方法探讨

摘要

Leakage is one of main technical parameters of insulated cryogenic vessel.Using leak testing technology of helium mass spectrometer to locate and test can be used to control the quality of the products.At first,two leak testing systems of he-lium mass spectrometer for insulated cryogenic vessel were compared and analyzed.In the same testing condition, if the posi-tion of the reference leak is different in the system,it will have an influence on the minimum detectable leakage rate、response time and leakage rate calculated value.Based on the analysis of the influence,the article puts forward some suggestions on the leak testing work.Secondly ,the selection principle of shunt leak testing method and no shunt leak testing method were discussed.The leak testing method of the fillet weld、butt weld、jacket leak、valve and the entire tank for 53 m3 LNG storage container were described.Attentions in the leak testing process were provided at last.%漏率是低温绝热容器产品的主要技术参数之一，利用氦质谱检漏技术对漏孔进行定位、定量检测可以起到控制产品质量的目的。文章首先对低温绝热容器用两种氦质谱检漏系统进行了比较和试验分析。结果表明：在测试条件一致的情况下，标准漏孔安装在系统中的不同位置，将对系统最小可检漏率、系统反应时间、漏率测算值产生影响。在对影响结果进行分析的基础上，对实际检漏工作提出相应建议。其次对分流和无分流两种检漏方法的选择原则进行了探讨。然后以53 m3液化天然气储运容器为例，对容器制造过程中的角焊缝、对接焊缝、夹层内存在的漏孔、阀门及容器整体的检漏方法进行了详述。最后对检漏过程中应注意的事项进行了说明。