It’s fun to exchange ideas on techniques with those who only have a superficial understanding of instruments!

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A few days ago, I was on night shift when I suddenly received a call saying that the level of the stabilizer tank was not appropriate and needed to be addressed! Upon arriving at the site to inquire about the process conditions, it was said that the instruments kept showing 100%. They thought it was correct, but their supervisor said that if the liquid level should be 0, then we need to come and take a look! Checking the trend, it was 98% 30 minutes ago and has been rising slowly to 100%. The on-site gauge showed 110%; no signs of silicone oil leakage were detected, and the 475 communication range remained unchanged! The medium is clean and stable gasoline at 200 degrees, so negative pressure blockage is impossible! The on-site glass panel also shows it’s full! Based on the above assessment, the instrument is functioning normally. Return to the control room and inform the operator that the instrument is fine; please check the process I gave a random phone report to the supervisor (who was at home), confirming that the instruments were working properly. Then the supervisor asked me how I had carried out the checks, so I explained what had happened. And that’s when something interesting happened: the process supervisor began to explain to me the working principle of double flanges! After all, he’s an experienced worker, so we should listen carefully to him. There’s nothing wrong with that. Later on, he started asking me what my double-flange *sealing oil* was, whether there was a leak, and asked me to fill it up! I said that the technology involved in filling with silicone oil is very complex; it’s difficult for many instrument manufacturers to ensure that there are no bubbles inside. Asking me to do this on-site? Are you joking? Besides, there’s no leakage of silicone oil at all! Then he asked what the range of your double flange was, and I said -33 to -7. He then said how could it be negative? Positive pressure is greater than negative pressure, so how can it be negative? At that moment I was completely speechless and replied, Do you even know what negative migration means? He stopped talking and asked me what density value I had set. I said it wasn’t a set value but needed to be calculated, so I did a quick calculation and got 0.72. He then said that was the density at temperatures below room temperature; ours should be around 0.68, and he asked me to change it. I replied that my reading was 110%, while he said it was zero, and wondered if such a 0.04 error could have such a big impact He had nothing more to say; he then asked whether the negative pressure was blocked, and asked someone to take it apart and check it for him. I said you’re the supervisor – don’t you know what condition your media is in? Do you think it might be blocked? I was so angry at that point that I just hung up the phone! It seems his analysis is sound, but he presents each point in such a ridiculous way! They kept calling me, but I didn’t answer! After a while, they just called and reported me to the dispatcher! The scheduler asked me directly; I repeated the exact words: The instruments are normal, check the process! The scheduler instructed the process to open the valves for discharging the material; after about ten minutes, the liquid level could be seen (the valves were not opened at first because it could affect the temperature in the downstream sections, and the process team did not dare to do so without authorization). It was the same as that on the glass panel! I said it’s okay, nothing’s wrong – I’m going to bed now! Encountering people who seem to understand but actually don’t is really amusing yet frustrating