Issues regarding the selection of absolute pressure transmitters
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Our company has a reaction vessel that operates under vacuum conditions during production (with a vacuum level of around 90%). The liquid medium inside is dimethyl phosphite, while the gas mixture contains chloromethane, hydrogen chloride, and other substances. During normal operation, the temperature is generally between 50 and 70 degrees; however, when the process is stopped, the temperature can rise to around 100 degrees. The reactor is currently equipped with absolute pressure transmitters of the EJA510A series; the material used for the part in contact with the liquid is Hastelloy C. However, only half a year after installation, inaccuracies began to occur, with a deviation of around 5 KPa from the actual pressure. Many such pressure transmitters in similar operating conditions have experienced this issue, but when the same transmitters are used in another type of reactor (with conditions otherwise identical except for a temperature range of 30–50 degrees), they can function properly for a long time. I’m not sure if it’s because of the high temperature, but such a temperature isn’t that high, really. Please, experts, advise if there are any good solutions. Thank you. (The voltage transformer is in contact only with the gas medium)
If you think it’s caused by high temperatures, you can try a remote-controlled type with a capillary: lol
It’s likely that the temperature used is too high. Although the temperature of the diaphragm can theoretically exceed 100 degrees, in practice problems tend to arise.