Method and apparatus for performing wireline logging operations in an under-balanced well

摘要

A method for performing logging operations in an underbalanced horizontal well without killing the well comprising: installing a downhole wet connector head (110) in a logging tool string (100); inserting the downhole wet connector head (110) and tool string (100) into a casing string deployed to a position adjacent a closed downhole deployment valve; installing a cable side door entry sub (16); inserting a wireline (13) to a pump-down wireline connector through the cable side door entry sub (13) and connecting the wire line (13); pumping the pump-down wireline connector to engage the downhole wet connector head (110); adjusting pressure between the underbalanced portion of the previously drilled well and the proximal portion of the drill string (25) above the pressure isolation valve (90); and, opening the closed pressure isolation valve (90) and moving the logging tool string (100) to the total depth to log the well without killing the well.