Mass flow meter calibration issues

In the calibration regulations of "JJG 1038-2008 Coriolis Mass Flow Meter", the standard devices of mass flow meters include mass method device, volume method device and standard table method standard device. Common verification methods include static weighing method, static volume density meter method, standard volume tube density meter method and standard table comparison method. Among them, the static weighing method requires a pool, water pump, weighing container, electronic scale, telescopic device, corresponding pipelines and calibration control system ； The static volumetric density meter method requires a pool, water pump, standard metal measuring instrument, telescopic device, corresponding pipelines for the online density meter and a calibration control system ； The standard volume tube plus density meter method requires a pool, water pump, standard volume tube expansion joint, corresponding pipelines for the online density meter, and a calibration control system ； The standard table comparison method requires oil pumps, oil tanks, standard mass flow meters, expansion joints, corresponding pipelines and calibration control systems ； Characteristics of the four verification methods: a. The static weighing method directly reads the quality. The error mainly comes from the electronic scale and commutator. The system has the highest accuracy level. It has loose requirements for the calibration environment. The calibration is less time-consuming and is not affected by the calibration medium and pipeline fluid pressure. However, on-site calibration is difficult. b. The static volume accelerometer method must measure the density of the calibration medium while reading the volume, which has additional errors. It has strict requirements on the calibration medium and calibration environment. The calibration is less time-consuming and is not affected by the calibration medium and pipeline fluid pressure. However, on-site calibration is difficult. c. The standard volume tube plus densitometer method also has additional errors. It has strict requirements on the calibration medium and calibration environment. The calibration takes a long time and requires the introduction of a pressure correction coefficient. However, the vehicle-mounted standard volume tube plus densitometer method is more convenient for on-site online verification. d. The error of the standard table comparison method mainly comes from the standard mass flow meter. It does not have high requirements for the calibration environment and calibration medium, but the investment is high.

If it cannot be calibrated at the production site, it can be sent to Shanghai Emerson for calibration, but it can be zeroed on site.

You can only mark the zero point on site. If you want to know whether it is accurate, you have to disassemble it and send it for inspection.

According to regulations, the calibration of mass flow meters must be sent to a qualified measurement department for completion. The description on the second floor is already very complete. Our measurement here uses the water mark method.

Although this answer is relatively comprehensive, some issues have not been noticed.: First of all, if you want a certificate as a legal measuring instrument, then you need to send it to your provincial measurement unit for verification and issue a verification certificate ； Secondly, if you want to verify whether this mass flow meter can still be used after a while, you can do it anywhere, or you can even connect a mass flow meter in series yourself for comparison. ； Finally, the test fee is about 2,000 yuan for an 80-caliber test. You can only give this to the people's government.

Contact the local metrology institute or provincial metrology institute. Of course, they can also come to your home for online calibration, but the cost is relatively high.