Abstract:

Used self-designed HTHP core filtration simple apparatus, similarly simulated borehole conditions to form mud cake,and examined shear cementing strength between~and cement slurry iwnot cleaning, cleaning, clearing and cleaning condilions. Moreover, used metal stick to simulate casing and didcorresponding experiment. The result was shown that the effect of the wettability of drilling fluid on cementing strength of I and II interfaces in cementing job was enormous; compered to wate-base drilling fluid, the interface cementing sirenformedfrom oil-base drilling fluid decreased by 15%.Consequently ,
it is very necessary to use wettahility reversal agent when designing pad fluid.

Key words: rilling fluid, wettability, cement job, I and II interfaces, cementing quality