Dynasonics DTTN series submersible transit time ultrasonic flow transducer made from CPVC rated to -40 to 194 deg F with 2-1/2 - 24 Inch pipe process connection. The DTT series transducers are non-invasive, clamp-on devices that are placed on the outside of a pipe. Proprietary circuitry allows this product to be used on both metal and plastic pipes containing relatively clean liquids as well as those with suspended solids or entrained gases. Models are available for general purpose, submersible or hazardous area applications.
Operating Principle Each transducer utilizes a piezoelectric crystal to transmit ultrasound through a pipe wall and into a flowing liquid. The ultrasonic signal is reflected from suspended solids or entrained gases drawn out of solution by hydraulic disturbances such as a 90° elbow. (This unit can measure the flow rate of clean liquids by mounting the transducers 1 to 3 pipe diameters downstream of the 90° elbow.) A second transducer receives the reflected sound and the TFXL series meter's circuitry compares the transmitted and received frequencies. If the liquid is moving, a frequency (phase/Doppler) shift occurs which is proportional to fluid velocity.
Clamp-on transducers that are suitable for pipes 2 inches and larger with a temperature range of -40…194° F (-40…90° C). The upper end of the pipe range varies with ultrasonic properties of the liquid and pipes. For water in PVC pipe, DTTL transducers are recommended on pipes 24 inches or larger. DTTN transducers are also available with intrinsic safety and for submersible applications.
Transducers include stainless steel straps and can be ordered with flexible armored conduit.