Larry Graham. Mark Haugland. Gary Frisch, Halliburton Energy Services
Data from field tests of a new flux-leakage/eddy-current wireline logging tool are presented. This device is used to inspect well casings in place. Images of both the inner and outer surfaces of the casing can be produced using the high resolution data provided by this tool. A real-time signal processing algorithm is available to enhance the raw data. The signal processing algorithm is described, and then several examples of applying the algorithm in different wells are given. Both conventional data presentations and images are shown. The paper gives important details about the tool and some results of testing the tool on well casings which have known artificial defect arrays. It is shown that holes as small as l/8 in. in diameter can be detected. Further, metal loss from as little as 10% of total wall thickness to 100% of total wall thickness can be identified by the tool. In addition to sharpening the resolution of the measurements. the enhanced signal processing algorithm can be used to classify joints of pipe as undamaged to extremely damaged: and. makes it easier to see small defects which are masked by background signal which is due to small scale surface roughness of the non-defected pipe. This pipe inspection device is a cost effective system for determining pipe conditions for repair. Remedial workovers, or adjustments to cathodic protection systems when needed. Usage's such as determining economic value of the pipe in P&A, exact location of perforations or leaks, periodic monitoring in gas storage or injection wells, and pressure limits for well servicing operations.