膜盒变送器故障原因分析

通过采用气相色谱、气质联用、扫描电镜-EDS能谱联用、傅立叶变换-红外光谱、模拟蒸馏、热重-质谱-红外联用等分析方法,对发生严重鼓包的膜盒变送器膜盒内的气体及硅油进行了分析,综合比较后可知,二甲基硅油发生的裂解是导致膜盒鼓包及产生黑色固体的主要原因,并进一步确定了二甲基硅油起始裂解温度为170℃左右,至300℃时裂解失重已达总重的2.9%。

Analysis of the Failure Cause of Membrane Box Transmitters

By using several analysis methods,such as GC,SEM-EDS,GC-MS,TG-MS-FT-IR,FT-IR,simulated distillation,the gas and silicon oil in the membrane box with serious bulge were analyzed.Comprehensive comparison shows that the pyrolysis of the dimethyl silicon oil is the main cause of the membrane box bulge and the occurrence of black solid,and the dimethyl silicon oil initial pyrolysis temperature is about 170℃.When it reaches 300℃,the pyrolysis weight loss of the silicon oil is up to 2.9% of the total weight.