The Largest Water Flowrate Calibrating Device in China

摘要

Along with the increasing of bore of magnetic flowmeter day by day, if the flowrate calibrating device used for large flowrate still adopts the traditional principle of high potential tank, steady head, the disadvantages of high investment, high power comsumption etc. will be manifested. To overcome the above mentioned problems, the Shanghai Welltech Automation Co. Ltd. constructed the large water calibrating device which adopted the principle of variable head dynamic volumetric comparison method. This device needs low power consumption and less investment. It can calibrate the water flowmeter with maximum diameter DN3000 (and can be extended up to DN3800) and maximum flowrate 25000 m~(3)/h. The total uncertainty of the device is 0.037% (k=2, p=0.95). The thesis stated the system, working principle, calibration method, uncertainty analysis of the device and the utilization of electronic scale within this device to trace the measuring value.