Establishing Design Criteria For Pressure Buildup Tests
Scott M. Frailey, Texas Tech University ; Aaron Pierce, Aaron E. Pierce & Associates; Gary Crawford, BP Exploration Inc.
The designs of pressure buildup tests are of equal importance to the analysis of the measured rate, pressure, and time data. Buildup analysis techniques are the focus of many texts, journal articles, and short courses, while discussions of the design of these tests are minimal. Many tests are unsuccessful as a result of poor or little design effort and inadequate instructions concerning field data acquisition An effective design not only maximizes the chances of a successful test, but also eliminates unnecessary testing. For example, a design recommendation may be not to conduct the test because the results cannot meet the desired objectives. This paper discusses criteria vital to an effective buildup design to insure the successful measurement of rate and pressure data. Factors which must be considered include: identifying test objectives, establishing the optimal rate and duration of the drawdown period, and determining the length of the shut-in period.