Flow error correction method for time difference type ultrasonic heat meter

The invention discloses a flow error correction method for a time difference type ultrasonic heat meter. The flow error correction method comprises the steps of selecting three basic flow points which are respectively distributed in three regions within a full-measuring-range flow range, and setting a standard compensation correction curve within the full-measuring-range flow range under the water temperature being M DEG C and a standard compensation correction curve of different water temperatures under the full-measuring-range water temperature on the errors of the basic flow points; performing calibration correction on the flow points under the water temperature being M DEG C, and saving a non-corrected flow value, an error correction compensation coefficient and the water temperature during calibration; correcting the compensation coefficient and the water temperature according to the errors of the basic flow points during calibration, and upwards or downwards moving the two standard compensation correction curves in a subsection manner according to the region to obtain real compensation correction curves of the ultrasonic heat meter; obtaining a real error correction compensation coefficient according to the two real compensation correction curves. According to the flow error correction method, the accuracy of the full-measuring-range water temperature and the flow error within the full-measuring-range flow range can be guaranteed, and the production efficiency is improved.