Frac Plug Evaluation to Improve Operations Efficiency

Abstract

Success of the unconventional resources (UR) operations is improving the efficiency by minimizing cost without compromising production. Plug and perforation (PnP) method is widely applied practice for unconventional wells completion due to flexibility of stimulating targeted intervals. One of the key parameters for operations efficiency of stimulation activities is utilization of fit for purpose frac plug to run with wireline PnP, proper frac isolation, and increasing efficiency of coil tubing mill-out. This paper provides comprehensive evaluation and comparison of various frac plug selection, execution and evaluation as well as optimization considering improving efficiency at multi-stage frac operations. To improve contact area with targeted formations, longer laterals are drilled and during milling operations, it can generate additional challenges to the milling efficiency due to decreasing weight on bit and potential lockups due extended laterals. There are various types of plugs in the market depending on the technical requirements of the operation such as composite, semi-dissolvable and fully dissolvable fracturing plugs. Therefore, the search to obtain the most optimum fit for purpose frac plug selection is critical with the objective of being milled with minimal weight on bit and low to no debris produced from milling activities. The application of a rigorous system for choosing frac plugs to be tested and implemented considers various well completion, formation, operational and technical parameters, while cross-referencing case studies and historical usage at different fields worldwide. For the current study, more than twenty frac plugs were systematically evaluated based on technical requirements, and were implemented across more than 2,000 stages of UR stimulation applications and coil tubing (CT) millout operations. Additionally, the paper discusses about contingency plans with solutions during wireline pump down and coil tubing millout operations challenges and opportunities. Fracturing plug manufacturers are continuously improving their frac plug technologies to meet customers demands of ease of use, applicability and functionality. Hence, the introduction and development of semi or fully dissolvable plugs. This paper highlights a full cycle of process for qualifying fracturing plugs for fit-for-purpose applications.