In the sewage treatment industry, the probes of ultrasonic flowmeters are easily contaminated by impurities and oil in sewage, resulting in weakened signals and reduced measurement accuracy. The following 4-step cleaning and protection plan can be adopted:
Step 1: Clean the probe regularly. It is recommended to clean the probe once a week (the frequency can be adjusted according to the sewage pollution degree). Before cleaning, turn off the equipment power and remove the probe. Gently brush off the scum and impurities on the probe surface with a soft brush (such as a toothbrush), then soak the probe in a neutral cleaning agent (such as diluted detergent solution) for 5-10 minutes, wipe it clean with a rag, and finally rinse the residual cleaning agent with clean water and dry it before installation. Note that strong acid and strong alkali cleaning agents should be avoided to prevent corrosion of the sensor on the probe surface.
Step 2: Install protective devices. For sewage pipelines with severe pollution, a protective cover can be installed outside the probe. The protective cover is made of corrosion-resistant materials (such as 316L stainless steel and polytetrafluoroethylene). A signal transmission hole is reserved on the protective cover to ensure that the ultrasonic signal is not affected. At the same time, a filter screen is installed upstream of the flowmeter (the filter screen aperture is determined according to the size of sewage impurities, generally 1-5mm) to reduce impurities flowing to the probe and reduce the pollution frequency.
Step 3: Adjust the probe installation angle. Tilt the probe installation angle slightly (at an angle of 10-15° with the horizontal direction of the pipeline) to avoid the probe facing the sewage flow direction directly, thereby reducing the direct impact of impurities on the probe surface. At the same time, ensure that the probe installation position avoids the bottom of the pipeline (sewage impurities are easy to deposit at the bottom). It is recommended to install it at a height of 1/2-2/3 of the horizontal diameter of the pipeline to reduce impurity adhesion.
Step 4: Calibrate the signal regularly. After cleaning the probe, the equipment signal needs to be recalibrated. Enter the “signal calibration” interface of the equipment and select “automatic calibration” or “manual calibration” to ensure that the signal strength is within the range required by the equipment (usually the signal strength value is greater than 80). If the signal strength is still low, check the coupling between the probe and the pipeline, reapply the coupling agent, or adjust the probe installation spacing until the signal is stable.
Post time: Oct-21-2025