Expansion cell molds

Expansion cell molds are designed to simulate the expansion properties of cement compositions placed into the annulus of a well. In a typical well cementing operation, a cement slurry is run into the annulus between the well casing and the bore hole, frequently at more than one location in the bore hole.

As the cement slurry hardens to a solid during the setting-up period, it is essential that the cement composition expand sufficiently to provide a good bond with the well casing and also the wall of the borehole. Otherwise, if the cement should shrink during hardening, it can leave channels between the borehole wall and the cement column and between the cement column and the well casing. This “channeling” effect is undesirable for several reasons. One reason is that gas or oil from a producing formation could leak into these channels and thus by-pass the production tubing which carries it to the well head.