Laboratory Experiments About The Acoustic Impedance And Compressive Strength Of The Low-density Cement

The acoustic impendence and the compressive of the low-density cement is different because of the different light weight addictives and the other addictives, which causes the wave propagation become larger, so conventional cement cementing quality can not accurately evaluate low-density cementing. The study on how the wave propagates in the cement made up of different light weight addictives, accelerants, retardants, fluid loss agents and high press curing based on the casing wave propagation in the casing well is necessary. Then we can modify the deviation of the evaluation standard in order to give some suggestions on how to improve the evaluation standard of the low density cementing.Researches show that, when adding the light weight addictives, the change amplitude of the cement stone’s acoustic is large; when adding the accelerants, the fluid loss agents and the retardants, the change amplitude of the cement stone’s acoustic is small. Apply geometry acoustics theory analysis and experimental laws, considering the first interface bond is good and casing wave amplitude subjects to the cement stone’s acoustic impendence, we can get acoustic impendence’s calculation formula of the 3 kinds low density cements and provide innovative approach for cementing quality evaluation. We should consider different temperatures’ effect on acoustic impendence because low density cement’s acoustic impendece is different when adding fluid loss addictive under different temperature. The drift beads micro silicon low density cement’s acoustic impendence change much under 10 MPa, so the alternative of the cement stone’s acoustic impendence should be considered under different pressures.