Maximizing inflow performance for any completion involves balancing the natural forces of the reservoir with the operational limitations of the well or field. In the case of soft or unconsolidated sand, completion procedures often dictate equipment or procedures that can potentially limit the inflow area by way of various forms of formation damage. There are three major types of formation damage: the filter cake and fluid loss damage associated with drilling; the skin increase due to compaction and debris associated with perforating; and, the skin added to the completion by the gravel or frac pack. While there are treatments that can remove or reduce the effects of damage, all of them involve subsequent intervention into the well, which elevates risk and as increases rig time. This paper discusses a recently developed one-trip completion system that has been successfully used to eliminate or reduce these causes of formation damage and improve inflow area and performance.
This new system provides a means of deploying a production liner, perforating, primary cementing, removing filter cake, and controlling sand production in a single trip. The one trip system is especially beneficial in wells needing sand control. The procedure utilizes a telescoping conduit that can be expanded hydraulically, mechanically, or both, to seal onto the formation face. The conduit is then cemented into place. The sand control media is inside the telescoping conduit in the form of appropriately sized stainless steel beads. The damage typically associated with the perforating phase is eliminated because there is no explosive discharge during the deployment of the system, and the well is brought on production normally. Studies have shown that decreasing initial perforation damage results in a more productive well over its lifetime. This new completion method also eliminates gravel packing, minimizes the amount of intervention into the well completion, and saves substantial rig time due to its one trip operation. Additionally, the authors will illustrate how the new completion simplifies operational logistics, especially in remote or offshore environments, because it is not dependent on large fluid pumping treatments nor does it require excessive pumping horsepower.