Arthur Metcalf & Thomas Dresher, Dowell Division of Dow Chemical
Limited information is available on the effects of pressure on the set properties of cements with respect to commonly used additives. This report presents compressive strength data on cement systems cured at temperatures of 170F 10 260F and at pressures of 3,000 to 10,200 psi. Of the cement systems studied, those designed, for a specific, bottom-hole static temperature (BHST) show little change in compressive strength with increased curing pressure at BHST. However, some systems, cured at temperatures lower than BHST, gave increased or decreased compressive strength with increased curing pressure. The use of" curing pressures that simulate more closely the pressures actually found in oil or gas wells gives a better understanding of additive performance and a more realistic waiting on cement (WOC) time for cement systems.