Three common piezoelectric materials have been studied for use in pulsed wave Doppler ultrasound, where high sensitivity is required, while bandwidth is less important. A large transducer aperture, 80 mm 2 , results in a low electrical impedance, making the transducers challenging to drive with conv...

Sealing of new wells, and the increasing need of plug and abandonment (P&A) of old wells, has triggered research and development of new methods for saving time at this operation. Shale has proven to seal off the annulus in longer well sections; however, the detection and qualification of the sea...

Ultrasonic tools are being used for imaging in a large variety of fields, spanning from medical applications in a hospital to applications deep down in oil and gas wells. When applying ultrasonic imaging techniques to image through elastic materials, such as steel, one of the main challenges these t...

Verification of annular barriers is essential for well integrity, with ultrasonic methods being central in well integrity testing for many decades. By doing ultrasonic pitch-catch measurements on a bench top laboratory setup developed to replicate an oil well casing, we were able to show that the be...

Dual-frequency band probes are needed for ultrasound (US) reverberation suppression and are useful for image-guided US therapy. A challenge is to design transducer stacks that achieve high bandwidth and efficiency at both operating frequencies when the frequencies are widely separated with a frequen...

Current methods for ultrasonic pitch-catch well logging use two receivers to log the bonded material outside a single casing. For two casings separated by a fluid, we find by simulation that increasing the number of receivers provides a better picture of the effect of the bonded material outside the...

This article presents a set of acoustic measurements conducted on the Statoil funded Behind Casing Logging Set-Up, designed by SINTEF Petroleum Research to resemble an oil well casing. A set of simple simulations using COMSOL Multiphysics were also conducted and the results compared with the measure...

This paper studies a design concept of a dual frequency ultrasonic transducer, in which we use different technologies for each band. A hybrid structure consisting of a piezoelectric stack used for the lower frequency (LF) band and a Capacitive Micromachined Ultrasound Transducer (CMUT) array placed ...

Phase velocity and attenuation of compressional and shear waves in the two materials PMMA and Eccosorb MF-117 were measured as function of frequency and temperature, using a broadband through-transmission technique. Two pairs of transducers were used for the measurements, one pair with center freque...