The Sensor Ball Revolutionizes Wireline Operations

Abstract This paper will share production engineering perspectives on the deployment of the sensor ball technology. The sensor ball is a new integrated production logging platform that was developed to measure primarily wellbore downhole pressure and temperature. The reduction in size of the innovative tool sensors has enabled packing of the tool in an attractive wireless manner. The sensor ball records wellbore data and stores collected data on electronic memory chips. The scope of this paper is to explain the working mechanism of the technology and outline the proper methodology for deployment by recapping the operational events of a successful sensor ball field trials on two water wells. The sensor ball is deployed and collected from the wellhead tree cap in a carefully designed sequence of operational steps to ensure no damage to the tool or tree valves can take place. The sensor ball has dissolvable weight element that allows for the tool to descend to the target measurement depth. The tool is made from material, with a specific density, that allows for buoyancy floating in water after the release of dissolvable weight. Conventional wireline gradient pressure and temperature surveys preceded the sensor ball runs during the trial phase. The objective of the wireline surveys is to provide a basis that qualifies the sensor ball data and quantifies its accuracy with respect to gauge measurements. The developed field trial test success criteria were: Successful mechanical deployment/retrieval of the sensor ball within programmed timeComplete data recovery from the sensor ball upon retrievalAccuracy of recovered data compared to wireline surveys below 5% average absolute error The comparison results of the sensor ball and wireline data at both water wells showed consistency and accuracy. The average absolute error was less than 3 % for pressure and temperature data. Further, the field trial has met all developed success criteria. The deployment of the sensor ball technology by oilfield operators will enable realization of several tangible benefits such as reducing acquisition time of downhole data compared to wireline and reducing manpower requirements for pressure and temperature surveys. The sensor ball enhancement to manpower requirement can allow for simultaneous data acquisition operations that were not possible with wireline surveys. Oilfield operators can avoid direct costs related to wireline units and associated equipment and its maintenance. Further, the typical mechanical risks associated with well intervention can be eliminated by deploying the sensor ball technology.