Abstract: A well bore is inspected to detect cement defects that can give rise to leakage. The well bore comprises an inner metal pipe. Outside the inner metal pipe its configuration may vary with distance from the top of the well bore in terms of concentric pipes outside the inner metal pipe and presence of cement between the pipes. A probe with is lowered through the inner metal pipe. An ultrasound signal is transmitted from the probe into the inner metal pipe and responses to the transmitted signal are received at a series of ultrasound receivers at different axial positions. A selection of a spatial frequency of waves arriving along the axial direction at the ultrasound receivers and/or the apparent velocity of said waves is retrieved dependent on the configuration. The received responses are band pass filtered accordingly.

Abstract: A method and device are discussed for determining quantitative parameters of a bond between two elements, for example an adhesive bond between two aluminium plates of an aircraft. A pulsed wave is provided to a first element. The elements, including the bonded region, act as a waveguide. Any discontinuities, an end of the bonded region or imperfections, result in a change of parameters of the waveguide. This results in reflections. By analysing characteristics of the reflections, along with the actual bond length and a signal expected from a good quality bond, an equivalent bond length may be determined.

Abstract: A well bore is inspected to detect cement defects that can give rise to leakage. The well bore comprises an inner metal pipe. Outside the inner metal pipe its configuration may vary with distance from the top of the well bore in terms of concentric pipes outside the inner metal pipe and presence of cement between the pipes. A probe with is lowered through the inner metal pipe. An ultrasound signal is transmitted from the probe into the inner metal pipe and responses to the transmitted signal are received at a series of ultrasound receivers at different axial positions. A selection of a spatial frequency of waves arriving along the axial direction at the ultrasound receivers and/or the apparent velocity of said waves is retrieved dependent on the configuration. The received responses are band pass filtered accordingly.