The factors that affect the measurement of the time difference external clamp ultrasonic flowmeter are:
1) The pipeline is old and the inner wall is seriously scaled;
2) The pipe material is uniform and dense, and the sound conductivity is not good;
3) Paint and other coatings on the outer wall of the pipeline are not removed;
4) The fluid in the pipeline is not satisfied with the pipe;
5) More bubbles or impurity particles in the pipeline;
6) The length of the straight pipe section is insufficient;
7) Valves, butterfly valves, etc. are installed near the upstream of the instrument installation point;
8) Frequency conversion interference, noise interference, etc.;
9) The fluid in the pipeline flows from the top down or the instrument is installed at the height of the pipeline, resulting in the fluid in the pipeline is not sufficient to collect the pipe or bubbles in the instrument installation;
10) The measured medium is a mixture or poor acoustic conductivity, such as raw sewage, mud, etc..
