Top Squeeze or Top Fill: Improved Secondary Cementing for Geothermal Wells

Abstract

Complete cementing of casing strings is critical in geothermal wells to protect the casing and provide mechanical integrity to the well bore. Surface indicators allow drilling personnel to select the best method for remedial cementing. The ‘top fill’ method is selected when cement is observed at the surface during the primary cement job, but the cement subsequently falls down the annulus. The ‘top squeeze’ method is selected when there are no cement returns to surface during the course of the primary cement job. For each case, specific procedures must be followed to successfully complete a remedial cement job. These procedures should be for planned in advance. In addition, these procedures are not dependent on the primary cementing technique, and can be used for any casing string that is run with a previously cemented casing string in place that has an annular preventer installed.