New Pressure-Actuated Valve Allows for Interventionless Access to Formation in Cemented Applications

摘要

Unconventional reservoirs require innovative completion techniques and technoology to become more economical. Formations vary drastically in lithology, lateral lengths, completion methods, and financial drivers. One of the most common techniques is the 'plug-n-perf' method. In the Eagle Ford, long-string completions arre the norm, with the production casing cemented in place along the horizontal section and up the vertical sectiion, providing isolation between frac stages and from other formations above and below the zone of interest. The Eagle Ford shale is a formation that produces gas, liquids, and oil,, depending on the area in South Texas being drilled. Operators are looking for ways to reduce cost and gain efficiencies when completing wells in unconventional reservoirs. One way of reducing cost is eliminating coiled-tubing-deployed perforations for establishing reservoir communication on the first stage of multistage frac operations. Technology has been developed which provides operators the option of placing a pressure-actuated valve above the shoe track, allowing for standard cementing practices. The new valve provides operators the ability to pressure test the casing and, through the use of applied pressure from the surface, activate into the open position. Once opened, information about the reservoir can be gathered that will influence the frac design before assembling the required pumping equipment. This paper presents multiple case histories showing different applications of the cemented pressure-actuated valve. The development history, reliability, and inherent accuracy are presented. This interventionless access technique has been proven effective in the Eagle Ford and Haynesville formations and is applicable in other unconventional reservoirs requiring multistage hydraulic fracturing.