延庆Matters needing attention in daily management and maintenance of mass flowmeter

① According to the requirements of JJG1038-2008 verification regulation, the mass flowmeter shall be verified by the verification institution authorized by the state with verification qualification, obtain the verification certificate and be used legally within the verification validity period. The verification cycle of mass flowmeter for trade measurement is 1 year.

② The mass flowmeter used for trade handover measurement should have stable performance and reliable operation, and the accuracy class should be greater than or equal to 0.2. The repeatability of the flowmeter should not exceed 1/2 of the absolute value of the allowable error specified by the accuracy and other accuracy class.

(3) In the metering terms of the trade handover contract, the metering method of mass flowmeter, the tolerance index of flow meter and the handling method in case of dispute should be clearly defined.

(4) Before the mass flowmeter is used, the working state of the mass flowmeter should be checked first, the color of the light should be checked, and the information should be alarm. The operation can only be continued after the relevant information is checked and confirmed.

⑤ In the loading process, the online temperature and density of each flowmeter should be recorded, and compared with the experimental standard density, so as to discover the abnormal flowmeter in time.

⑥ There are three ways to zero mass flowmeter, using ProlinkⅡ software, transmitter panel and manual zeroing, it is recommended to use ProlinkⅡ software and manual zeroing can accurately obtain zero. Adjust zero for 3 times consecutively and capture a good zero for storage. Zeroing should not be done at night and in bad weather to prevent errors. When the flowmeter is in normal use, the number of zeroing should not be too much. If the sensor zero adjustment is not appropriate, the measurement error will be introduced, leading to inaccurate measurement results.

⑦ To the flowmeter installation requirements: connect its flange pay attention to concentricity, verticality, levelness, to ensure that the installation does not produce additional stress. The flow meter is firmly supported to prevent vibration. The sensor shall be installed stress-free on the same axis of the pipe, and the sealing gasket shall not protruding into the pipe. Installation site should be away from large motor or magnetic field.