Optimizing Completions Cost by Using the Low Gravity Ball for Production Packer Setting Operations

Abstract

The completion cost of development wells is usually 30-50% of the Authority for Expenditure (AFE). This depends on the number of zones to be completed, the completions strategy, cost of downhole jewelries and complexity. The quest to develop these complex un-stacked reservoirs has increased the tortuosity of the well plan and the complexity of the wells. This has in turn increased the completion complexity and has significantly increased the time taken to deploy the completion accessories, and the time taken to set the packer. The sand management strategy and lower completion philosophy for the case study field, is setting Stand Alone Screens (SAS) as the lower completion assembly. Over the years, Addax Petroleum has used the metallic ball to set the lower completion production packer in a slightly straight well. Due to the need to optimize the well architecture and the tortuous profile of the well, the average production packer is now set at circa 80-85 degree's inclination. This optimization plan, significantly increased the amount of time required to circulate the metallic ball to the lower completion ball seat (a device engineered to aid the setting and hanging of the lower completion assembly in the production casing). This increase in time has further increased the completion costs. To ensure that the development cost is reduced due to the current unstable and low oil price, a plastic setting ball (with lower specific gravity) was identified, risk assessed and used successfully to significantly eliminate the excess time for completion operations. This paper reviews the challenges experienced using the metallic packer setting balls in highly tortuous horizontal wells. It also shows and discusses the huge cost savings achieved in case study wells where the low gravity packer setting ball was used to set the lower completions production packer.