Multistage Hydraulic Fracturing Using Coiled Tubing-Activated Frac Sleeves: Case Study From The Permian Basin

Abstract

Abstract Tremendous quantities of unconventional hydrocarbon reserves have been discovered globally. These discoveries have increased the total oil and gas reserves worldwide and in the U.S. specifically. However, safely and economically unlocking these hydrocarbons trapped in shale plays and other tight formations require the use of the latest drilling technologies and the best multistage hydraulic fracturing techniques. Horizontal drilling and multistage hydraulic fracturing have had a great impact on U.S. oil and gas production. Daily crude oil production has increased by an average of 2 million barrels from 2010 to 2013 (EIA 2013). Unconventional reservoir conditions generally mandate the use of hydraulic fracturing to produce commercial volumes of oil and gas. Fracturing technology continues to evolve rapidly and the new technologies primarily focus on making the process more efficient, cost effective and environmentally friendly. This case study presents an operational review of the successful stimulation of a Bone Spring horizontal well in Lea County, NM. The stimulation treatment consisted of 29 frac stages and used coiled tubing-activated frac sleeves (CTFS) technology in the Permian Basin. This paper discusses the results and information gathered during the execution of the operation. The CTFS is a cost-effective and efficient multistage fracture stimulation-completion system. The system has been used extensively in Canada. This patented technology effectively reduces the required hydraulic horsepower, fluid usage, and downtime between frac stages. The CTFS is compatible with open-hole or cemented completions and provides full wellbore access without milling for unobstructed production. The bottom hole temperature and pressure are recorded using memory gauges attached to a coiled-tubing (CT)-deployed bottom hole assembly (BHA) for post-treatment analysis and diagnostics. The system provides rapid recovery from screen-outs, minimizing downtime and adding flexibility to treatment design. In the Permian Basin, the "plug-and-perf" multistage fracturing technique has been predominant for years. However, this technique is costly and time consuming, as it requires fluid and time to pump the wireline BHA down into the horizontal well section, in addition to having to mill-out plugs to initiate production. The CTFS technique, on the other hand, utilizes frac sleeves that are hydraulically opened using a CT BHA, which saves significant amounts of time between stages and reduces fluid consumption. The single frac fluid entry point allows tighter spacing of frac stages and ensures that the fracture is created at the sleeve, which is in contrast to the multi-cluster techniques, in which some zones can remain untreated. The CTFS has been shown to be a fast and effective multistage stimulation technique. The use of this technique efficiently minimized the non-productive time (NPT), considerably reduced the fluid consumption and shortened the post-frac cleanout time.