| Popis: |
When the first frac pack was performed in the Gulf of Mexico (GOM) over a decade ago, very little was known about the effects this form of sand control would have on the intended formation. Even less was known about how to optimize the treatment to get the most benefit for the formation. Since that time, the sand control community has learned a great deal about the effects and benefits of frac packing various unconsolidated formations throughout the world. However, most of the knowledge and design criteria have been housed within the minds of individuals and cannot be looked at as a whole to find trends and fine tune the design methods currently being used. Another complicating factor is the number of frac models being used within the industry with varying degrees of complexity. Therefore, even though thousands of frac packs have been performed globally, frac-pack redesign methods are still subjective and differ from individual to individual and model to model. The recent creation of a database that houses selected formation evaluation test (FET) and frac data, along with model-specific parameters, allows full-scale analysis of a large number of jobs pumped in the Gulf of Mexico. With a consistent analysis procedure in place, the database, populated with numerous treatments by engineers working throughout the GOM, can be analyzed objectively. The data contained in this database include rock mechanics, net pressures, pumping trend data, tip screenout (TSO) times, etc. This paper explains the methodology and discusses the results of the database analysis, using case studies to determine the best method for analysis of the jobs. Crossplots show the correlation between TSO prediction and actual events and suggests recommendations for more successful future design work. This paper is meant to give up-to-date guidelines to help design better frac packs. |
