The Nominal Sand-Control Screen: A Critical Evaluation of Screen Performance

Abstract

Summary Over the past few years, several premium sand-control screens have been introduced into the market. The proliferation of new screens has raised questions about how to choose the proper sand-control screen for a particular formation. To address this concern, a project was initiated at ChevronTexaco Exploration Production Technology Co. (EPTC) to devise a method to evaluate sand-control screens. As a result of this program, a method has been standardized for the evaluation of sand-control screens. The method, known as the screen efficiency (SE) test, shows the relationship between normalized sand-control characteristics (i.e., sand-control factor) of the screens and the normalized length of time it takes a screen to plug under a certain set of conditions (i.e., the performance factor). The results of SE tests to evaluate several sand-control screens for a North Sea and a west Africa field are discussed in the paper. The data in this paper also document that the numerical ratings given by the manufacturers are generally not very useful in understanding the sand-control rating of the particular screen or in comparing screens from different manufacturers. In addition, the effect of particle size distribution and sand concentration on the relative performance of sand-control screens was demonstrated by a comparison of SE plots of sands from the North Sea and west Africa fields.