Our Sonic Casing Inspection Tool
Magnetic Casing Inspection Tool
The principle of the tool is that a narrow pulsed acoustic beam scans the inside of the casing in a tight helix as the tool moves up the hole.
To scan the casing wall, the acoustic beam generator is rotated by an electric motor. During the rotation of the beam pulses of acoustic energy are sent towards the casing. Acoustic energy is reflected form the casing and the amplitude and travel time of the reflected signal are measured with the same transducer that generates the acoustic beam. The tool records 256 amplitude and travel time values per revolution, the transducer rotates at 7 revolutions per second. As the tool moves up the hole a detailed 360 degree image of the casing is produced.6
This tool is electro magnetic in design and uses alternating current to create a flux field that extends outside the casing. By focusing special wound coils, we are able to see any disturbance in the flux field indicating a change in casing. To calibrate the tool we use two pieces of the same size casing each being of different weight ( wall thickness ) of the casing that we are going to log, giving an accurate wall thickness along with any variations caused by pitting ( inside or out ), perforations, collars, holes and changes in pipe size or weight.
All of the processing of raw data is done in the field.