Use of Expanding cement for squeezing Casing Leaks

This paper describes the use and results of using expanding cement to repair casing leaks in West Central Texas. In the past, casing leaks were squeezed using Class C cement (high sulfate resistant. This would take from three to five hours and often several stages, The use of expanding cement has cut the time required for squeezing to one-half to two hours, usually requiring only one stage. This method uses the high gel-strength cement to hold its own hydrostatic pressure to give a quick shut-off to casing leaks. The weight of this cement is heavier than ordinary Class C cement.