Improving zonal isolation horizontal configurations Dynamic cement placement approach
Description: 14 pDDC classification:- PD I116 1 0015668
| Current library | Call number | Status | Barcode | |
|---|---|---|---|---|
| Colección Digital IAPG | PD I116 1 0015668 (Browse shelf(Opens below)) | Not for loan | 200063825 |
The increasing energy demand has led shale unconventional reservoirs to become a focal point for operators worldwide. Over the past decades, several technological advances conveyed to drilling and completing horizontal geometry wells in which ulterior massive hydraulic fracture treatments are deployed to improve production of these reservoirs, technically but not economically recoverable. Argentina, which counts with one of the largest shale-stored hydrocarbon reserves in the world, has become one of the leading countries in unconventional reservoirs completions, having horizontally-drilled wells number increased over the past decade. This fact has generated the need to find solutions operationally and economically viable to successfully cement horizontal wells, achieving proper zonal isolation. Since the difficulties encountered in Neuquén’s wells, such as channeling, differential fluid velocities, among others, most of them not possible to overcome, the need to implement casing movement while cementing as a practical solution had arisen. Studies have shown that displacement efficiency can top as much as 50 % when there is no pipe movement to increasing up to 100 % with movement, in which rotation shows to be the preferred pipe movement because of the azimuthal forces exerted on the fluid that cause it to be completely swept away around the annulus. The challenge is to incorporate previous experience in the field and introduce casing rotation for dynamic cementing. This mechanical method, although proven to be the most cost effective, has remained as one of the least accepted solutions, due in large part to the misconceptions and the fear that the high torques during the cement pumping/displacement will cause casing failures. In a recent campaign, the last well considered rotation in the production section-cementing job. Rotation was enabled from circulating mud prior cementing until displacement and bumping the plug. A rotation speed sensitivity was analyzed to determine the optimum angular speed and according to the torque capabilities (connections and surface equipment) an optimum rate of 30 rpm was proposed. This well was cemented obtaining congruent results from comparing bond logs and fluid placement simulations. This project focuses on the definition of the factors contributing to a successful cementing job in an horizontal geometry, the aspects that need to be analyzed from the cementing perspective when rotating casing to aid in mud displacement, and the evaluation related to the wells cemented under these circumstances compared to the simulated results predicted during the design phase of the well.



