High pressure isolation system for well stimulation through production tubing

摘要

A fracturing system includes a fracturing spool that mounts onto a wellhead assembly for injecting fracturing fluid into a well beneath the wellhead assembly. The fracturing system includes an isolation sleeve and fracturing spool. The isolation sleeve inserts in an axial bore of the fracturing spool, and has a lower end that extends into the wellhead to isolate and protect portions of the wellhead assembly from the fracturing fluid. A groove in an inner surface of the fracturing spool receives an annular seal for sealing between the isolation sleeve and fracturing spool. Injecting a viscous fluid into the groove energizes the seal, and blocks high pressure fracturing fluid from flowing between the isolation sleeve and fracturing spool.