Cemented Multi-Stage Fracturing Systems Enhancing Risk Mitigation and Time Efficiency – A Game-Changing Alternative to Open Hole MSF and Cemented Liners

Abstract Deployment of Open Hole Multistage Fracturing (OH MSF) completion system in long horizontal wells has always been a daunting task, and often presents high risk of getting stuck in open hole due to complex completion design with very stiff assemblies that include multiple large OD – hydraulic set open hole packers. This paper introduces a novel technology called Cemented MSF, which addresses the deployment risks associated with conventional OH MSF and cemented liner. Notably, this technology eliminates the need for time-consuming coil tubing operations for plug-and-perf (in cemented liner), thereby avoiding production delays. The paper examines the major bottleneck in deployment of OH MSF, a very stiff completion string, which is particularly influenced by the number of stages/ open hole packers, elevating the risk of equipment getting stuck in the open hole due to ledges and washout created while drilling the reservoir. Consequently, there is a constant trade-off between maximizing deployment chances and minimizing the risk of getting stuck by reducing the number of stages. However, this trade-off comes at the expense of production efficiency. Cemented MSF is a hybrid integrated system that provides all the production benefits of OH MSF with significantly reduced deployment risk. In this novel solution, OH packers are eliminated, and the completion is run in a similar process like a cemented liner. The cemented MSF lower completions were successfully implemented in a long horizontal well with 6,000 ft of reservoir contact. While drilling the lateral section, this system enables greater degree of directional flexibility and navigation control as compared to conventional OH MSFs, which have very strict limitations for dogleg and inclination citing risk of deployment complexities with the stiff completions string. Having no OH packers eliminate the need to record open hole logs for packer’s placement and further eliminates the need for a simulation run (Dummy Run) to simulate actual completion string stiffness, resulting in a direct savings of minimum six-days. Furthermore, to ensure that the frac ports are not activated prematurely, a fit for purpose cementing program was developed using precise volume and hydraulic displacement calculations and optimum shoe track length. Among the unique features of this system is its ability to run maximum possible stages, ensuring that productions will not be compromised. At the end of completion phase, the frac Ports can be activated by dropping balls just like a conventional OH MSF system and get the well for production. The paper outlines essential design considerations, checkpoints, an execution phase roadmap, and potential contingencies related to the deployment of the Cemented MSF technology.