Suggestions on the revision of SY/T 6658-2006 measurement of natural gas flow by vortex precession flowmeter

Vortex precession flowmeter is widely used in the field of natural gas sales terminal measurement, as the technology of flow measurement advanced and the field using experience accumulated, it is necessary to revise the standard of SY/T 6658-2006 Measurement of Natural Gas Flow by Vortex Precession Flowmeter. The main difference of technical terms of standards of vortex precession flowmeter between national and international were contrasted and analyzed, and the test results shown that the maximum performance deviation of the vortex precession flowmeter can reach -0.7% when installing the reducer pipe and the elbow pipe with different lengths of straight pipe. It is suggested that the requirements of accuracy level, repeatability and real-flow calibration should be unified with the relevant technical provisions of national verification regulations, the requirements of turbulent flow test and installation process should be improved, and the display and output function and flowmeter correction method of energy measurement should be increased when SY/T 6658-2006 is revised.