Richard Montman, David Sutton, Weldon Harms, & Bharat Mody, Halliburton Services
The routine use of minimum density cement slurries (4-11 lb/gal) in oil field applications has been limited in the past; primarily because no convenient, cost-effective process existed which could provide useful compressive strength development at low densities. The careful selection and use of surfactants and foam stabilizers in addition to the use of properly designed field equipment has enabled the mixing and placement of stable foam cement slurries with instantly variable, but controllable downhole slurry densities from 3.5 - 14 lb/gal over a wide range of conditions. Typical physical properties such as compressive strength, porosity, and permeability for foam cements of various densities are presented. Foamed cement slurries have been successfully applied in the oil field on squeeze jobs, leaking LPG underground reservoirs, salt-zone wash-outs, as well as primary cementing jobs. Job histories covering 31 field jobs will be discussed.