Abstract
Traditional intervention operations with coiled tubing (CT) in extended reach horizontal wells might be difficult to access due to lockup from frictional forces and operational inefficiencies. Using conventional shifting tools requires multiple runs to shift open and close multiple sliding sleeve doors (SSD). This paper is a case study of an electric-line powered shifting intervention operation to shift open an SSD, circulate fluids though the sleeve and into the annulus, and then close and repeat this for another SSD in a long horizontal well—all in a single run.
The paper discusses the different methods that can be used to efficiently seek and latch onto the shifting profiles using a tractor, wireline cable, and the shifting tool itself with an inchworm motion. The electric-line shifting tool monitored and verified the opening and closing of the sleeves in real time using its onboard sensors. These techniques were effectively deployed in multiple wells that required the annulus to be displaced with fluid after running smart completions. The completions were installed in the well with the SSDs in a closed position, and the shifting intervention consisted in opening the SSD, pumping fluids through the sleeve, and closing the SSD. The tool was anchored in place in the wellbore during the entire circulating operation, and the SSD was subsequently closed. This operation was then repeated on the second SSD in the wellbore, and the entire operation was completed in a single run. Also, no additional caliper run was needed as the shifting tool verified the position of the SSDs.
These methods were used in a long horizontal well with the help of real-time measurements. The tool measurements identified if the SSDs were in open or closed position or anywhere in-between. The shifting tool provided confirmation via its measurements that the sleeve was not partially open. This was particularly important when pumping fluid through the annulus to achieve the maximum flow through the sleeve. Operating using electric-line was extremely efficient and eliminated the need to perform multiple runs, thus achieving time savings on the rig.
This is the first time that a paper discusses the different seek methods that can be used for carrying out a electric-line mechanical intervention operation. It represents a novel method using a shifting tool as a caliper to probe and measure the completion inner diameter changes while seeking for the profile. It provides a valuable method for reliably and confidently locating and latching onto a shifting profile. Finally, this is the first time that a paper correlates the theoretical mechanics of shifting a sliding sleeve with consistent results from system integration tests and downhole measurements from the real job.
Optimization of shale-gas horizontal well spacing based on geology–engineering–economy integration: A case study of Well Block Ning 209 in the National Shale Gas Development Demonstration Area