Squeeze Cementing

Squeeze cementing is selective cementing downhole, within the casing. This technique might be used to seal off casing leaks caused by corrosion or to repair channels that occur behind the casing during primary cementing. A drillable plug is placed in the casing below the point where the squeeze cementing is to occur. Tubing with a packer is then run into the wellbore, and the packer is set in the casing above the point at which the squeeze cementing is to occur. Cement is the pumped under pressure through the pipe and squeezed into intervals perforated for this purpose, or theough the leaks, to seal the annulus and therefore the leak at that location. After the cement has set the packer is released and the tubing is retrieved to the surface. It is then necessary to drill out the set cement remaining in the casing, and the plug set in the casing below the cement.