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Are you maintenance after the rainy season?

Flowmeter maintenance issues:
(1) The probe of the vortex flowmeter should be cleaned regularly. It has been found in the inspection that the individual probe detection holes have been blocked by dirt and even wrapped in plastic cloth, which affects the normal measurement.
(2) Since the determination of the K-factor is very important in the whole process of the vortex street, the accuracy of the K-factor directly affects the accuracy of the loop, the replacement of the parts and the wear of the process piping, etc., may affect the K-factor. . However, the chemical plant lacks the means and ability to calibrate. It can only be sent to the calibration. Due to the influence of the process operation, it is necessary to remove the vortex from the pipeline and send it for 5 or 6 days. The process is difficult to meet, so it is impossible to determine K. coefficient. This year, through the transformation of flow meters, although there are already vortex calibration conditions with smaller calibers, there is still no way for large-diameter vortex streets. In the future, we should pay attention to the use of vortex street calibration methods, using standard frequencies and portable ultrasonics. Flowmeter, measure the instantaneous flow in the pipeline and the pulse output frequency of the sensor, calculate the K factor on site
(3) Installation of a humid probe. It should be dried once a day or as moisture-proof. Since the probe itself is moisture-proof, it will affect the operation after damp.
(4) Regularly check grounding and shielding to eliminate external interference. Sometimes the problem is indicated as a result of interference.

(5) The management of the data of the instrument should be given enough attention to facilitate future work.

So what do you need to pay attention to in daily maintenance?
1: Manual zero adjustment method: refers to the manual zero adjustment of the differential pressure gauge with a multimeter. This method can be used when the differential pressure transmitter has a slight drift. The method is as follows: the differential pressure transmitter has positive , negative two signal lines, remove one of them, the multimeter is adjusted in the 4-20mA DC gear position, the multimeter is stringed in, the differential pressure transmitter has a zero adjustment screw (the zero is the zero adjustment button) When the hour hand is adjusted, the current increases, and the counterclockwise direction decreases. When the multimeter displays 4 mA, the zero point is adjusted at this time.
2: Valve switching sequence during condensation (mainly for steam): In normal operation, the three-valve intermediate valve is closed, and the two-side valve is open. If it is necessary to drain or recondense, first close the two valves and then open the intermediate valve. After that, the root drain valve is opened for sewage discharge. If the condensation is completed, the intermediate valve is closed, and then the two sides of the valve are slowly opened, the system is in normal operation.
3: When the measuring medium is steam, the on-line zero adjustment should be performed because there may be a slight difference in height between the condensing discs during installation. When the measured fluid flow rate is small, the height difference has a greater influence on the flow rate. (100Pa for 1cm water column)

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