This tool is designed to investigate variations of metal thickness
within downhole tubulars. It is run centralised within a wellbore,
ideally combined with a Multifinger Imaging Tool or with MIT data
available. The tool has an array of 12, specially developed, miniature
magnetic sensors mounted on the inside of a set of bowsprings. Each
sensor of the array measures a magnetic value and all 12 values are
simultaneously transmitted to the surface where the waveform is
recorded. WIVA software is available to create and display
a 3D image of thewellbore. The tool is designed to be able
to pass through tubing to log casing up to 7in.
Description
The tool generates an alternating magnetic wave, which propagates out of the tool and permeates through the casing. Once outside the casing, the wave travels a short distance along the length of the pipe, before re-entering the well bore in order to complete its path. It is in this region, where the magnetic wave re-enters the well bore, that the sensor array is positioned. Each sensor then detects localized information about the magnetic wave that has travelled through the casing wall.
The velocity and amplitude of the emitted magnetic wave are affected by the thickness of metal through which it has travelled. Greater metal thickness results in slower wave propagation and greater attenuation. As a result a sensor that is adjacent to an area of thinner metal will receive a wave of greater amplitude some time before a sensor that is adjacent to an area of thicker metal. These differences can be used to locate and quantify variations in metal thickness along the tubular.
Features
- Inspection of Tubing and casing for internal & external metal loss.
- Casing can be logged after the tool has passed through restrictions.
- Measures absolute wall thickness.
- 3D visualisations provide powerful qualitative images of well condition.
- Detects pitting and gradual wall loss.
- Requires MIT data for internal diameter.
- Requires centralisers.
- Combines with other Ultrawire™ tools.
