Cement Evaluation Tool
The Cement evaluation tool (CET) uses ultrasonic acoustic pulses from a rotating transducer and measures radially instead of axially. The transmitter emits ultrasonic pulses between 200 and 700 kHz and measures the received ultrasonic waveforms reflected from the internal and external casing interfaces.

The rate of decay of the waveforms received indicates the quality of the cement bond at the cement/casing interface, and the resonant frequency of the casing (Casing
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