Radar level gauge
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The level of chloromethane is measured by a radar level gauge (LR-400). When feeding chloromethane begins, the readings for the first 3 cubic units are normal, but after that the display stays unchanged. Upon visiting the site, it was observed that vaporization inside the tank was quite severe, and the pipes were vibrating greatly. The volume display remained at 3 cubic units, and the liquid level stayed at 3.2%; from the second day on it showed 100% without any change. All settings were checked and found to be correct. I believe it’s a loss of wave signal issue, caused by the vaporization of chloromethane, which prevents the wave signals sent by the level gauge from being reflected back or makes it impossible to receive those reflected signals. I suggest that the company switch to a radar level gauge equipped with a cable. Everyone, could you also help check whether my approach is correct? I also hope to receive better suggestions and opinions.
Try to avoid using radar if possible. It’s easy to go crazy when there are ghosts.
Guided wave radar + guide rod does indeed make a big difference
If the tank is not very tall, it’s best to use a rigid rod radar.
It turns out that this phenomenon occurs quite often; it’s not just our family that experiences it, which shows that radar level gauges are unreliable. We also experienced exactly the same phenomenon with one of our liquefied gas cylinders, just as described by the original poster.
Radar level gauges all have blind zones, which can be adjusted; the reading doesn’t change once the liquid level exceeds that blind zone
In such operating conditions, how can a contactless solution be chosen? Not to mention the interference caused by the curved bottom of the tank, the dielectric constant of liquefied chloromethane is extremely low, allowing electromagnetic waves to penetrate the interface; as a result, the signals received by the instruments are always false echoes reflected from the tank bottom. The signals reflected at the interface are weaker than those reflected from the tank bottom, so the readings will certainly be inaccurate. A contact-based guided-wave radar with a cable connection yields much better results