Ultrasonic flow meters are categorized into three types based on the sensor installation method: clamp-on (external mounting), insertion, and pipe section type. Clamp-on ultrasonic flow meters are non-contact instruments, less affected by the parameters of the measured medium, and are particularly suitable for flow measurement of high-pressure pipelines, highly corrosive, non-conductive, radioactive, and flammable/explosive fluids. Installation is simple; the pipe does not need to be cut off. The magnetic sensor can be directly attached to the outer wall of the pipe, secured with professional clamps, achieving truly non-destructive installation. Changes in pipe diameter have little impact on the cost of clamp-on ultrasonic flow meters, making them an economical instrument. After wiring, the sensor can be potted to achieve an IP68 protection rating, suitable for harsh environments.
Insertion ultrasonic flow meters require drilling holes in the pipe and welding the sensor base during installation. They are suitable for pipes with diameters greater than DN100, and for old pipes with severe scaling or uneven structure. When the pipe material is a poor conductor of ultrasonic waves, such as cast iron, cement, or fiberglass, or when the external clamp-on ultrasonic sensor cannot achieve the required signal strength or the measurement is unstable, or when the measuring section of the pipe being tested is in a state of water accumulation for an extended period, an insertion ultrasonic flow meter can be selected. The installation requirements for insertion ultrasonic flow meters are higher than those for clamp-on types, especially the selection of the measurement point.
Pipe-section ultrasonic flow meters have the sensor parameters pre-configured on a straight pipe section at the factory, avoiding errors and impacts caused by improper operation or incorrect parameter input during installation of clamp-on or insertion ultrasonic flow meters. The cost of the pipe-section ultrasonic flow meter sensor increases with the pipe diameter, and installation requires cutting the pipe, making it slightly more labor-intensive and complex than the other two installation methods.
