Patent ID: 7243727
Filing Date: 2007-07-17
Classification: E21B

Abstract:
1. A method of fracing or stimulating a formation, comprising: associating a straddle packer with a coiled tubing string via an isolation assembly; straddling a zone to be fraced with the packer on coiled tubing; setting the packer; pumping fluid through the coiled tubing, through the isolation assembly, and into the packer; bleeding back a pressure of the fluid in the coiled tubing string, thus closing a check valve in the isolation assembly, the packer remaining set; providing fluid communication through a plurality of aligned ports below the check valve in the isolation assembly and into the annulus, by providing fluid communication through a shuttle port in a shuttle of the isolation assembly, the shuttle adapted to move upwardly with respect to a housing having a housing port of the isolation assembly, when an upward force on the check valve exceeds a downward force of a shuttle spring, the shuttle moving upwardly within the housing until the port in the shuttle at least partially aligns with the port in the housing; the fluid communication through the ports and into the annulus allowing the pressure inside the packer to equalize with the pressure of the annulus to unset the packer; and repositioning the packer within the casing.