A Study of Cement-pipe Bonding

The emphasis placed on bonding with the introduction of Acoustic Cement Bond Logs has led to a study of many of the variables influencing this property, as well as methods for improving bond at the casing-cement interface. Special cementing problems concerning gas storage wells and tubingless completion wells have also indicated the need for better pipe-cement bonding. This presentation stresses some of the problems involved and possible solutions. The application of a resin-sand coating at specific points on the casing will give a greater adhesion at cement-pipe interface. Resistance of the cement-pipe bond to fluid intrusion and loading is greatly increased. Laboratory and field results as well as acoustic logs emphasize the improvement in bonding when a roughness factor is introduced. Comparative bonding data both with and without mill varnish on the pipe are also evaluated.