Cement sheath shrinkage after placing the cement slurry in the annulus has been of concern in oilwell cementing because of the potential detrimental effects that shrinkage can have on long-term zonal isolation.

This paper compares several methods for measuring cement shrinkage under a variety of conditions including those downhole. Using the various methods, cement shrinkage in environments where the cement slurry is either closed to or open to external water sources was measured and the values were compared. The methods used for measurement under atmospheric conditions were based on API test apparatus (balloon and ring-mold) and flask methods currently used in field labs. Measurements under pressure and temperature were performed using the ring-mold method, in-house designed equipment, and newly available commercial equipment.

The values obtained by the different methods are discussed. Procedure modifications are proposed for measuring volume changes to cement slurries based on placement time, shear history, and gel-strength development.

The results presented in this work can be used to test shrinkage characteristics of cement slurries in the lab, under downhole conditions, and to select a cement system that is fit for purpose.

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