An operator in Alberta, Canada, needed to restore casing integrity in a well where a frac port had opened prematurely. Any repair had to allow passage of frac balls, the largest of which had an OD of 3.25 in [82.55 mm].
After killing the well, the frac port was milled out to a maximum permissible ID of 4.56 in [115.82 mm]. Subsequently, SLB placed a reinforced expandable steel patch to seal the leaking port. The top and bottom of the patch were set in 4.89-in [124.21-mm] casing ID, while the central part was molded across the restricted-ID frac port. A drift ring confirmed a final ID of 4.193 in [106.5 mm], enabling fracturing operations to restart and the largest frac ball to pass through easily.
All remaining 29 stages of the well were fractured at 8,400 psi [58 MPa] with a pump rate of 44 bbl/min [7.04 m3/min]. No leaks were observed. The repair was a major success for the operator because the well became one of its highest producers in the Cochrane area.
