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With the continuous increase in the pace of oil exploration and drilling technology improved , especially with the probe deepening , deep well , ultra-deep , complex wells , long cementing segment well , well easy Dropout increasing conventional slurry system can not meet the requirements of such well cementing . Important for the oil and gas layer protection and improving the quality of cementing and low density slurry . A lot of literature and information : cement , drift beads , micro- silicon a reasonable ratio experiment preferred , can be adjustable density range , and cement paste pore structure has been improved , and a significant reduction in the low permeability and strength . The dense slurry system . Experimental Study : The optimal dosage of the dispersant ranges from 1.2 to 1.5% . Fluid loss additive dosage reached 1.5% , the loss of water has been reduced to the extent required by the low-density cement slurry . By different formulations and different curing time of the cement paste compressive , flexural strength experimental comparison : early strength agent can significantly improve the early strength of the formulation of cement stone , early strength agent dosage range of between 1.2 to 1.8% . Finally, the low-density formula : Sheng Wei River class G cement ( water-cement ratio of 0.83 to 1.20 ) drift beads ( 20 to 50%) and micro- silicon ( 13 to 23%), fluid loss agent ( 1.5 to 2.0% ) dispersant ( 1.2 to 1.5 %) early strength agent ( 1.2 to 1.8% ) . Drawn in accordance with the preparation area density of the slurry system adjustable range , has good stability , liquidity and certain thixotropic , low water loss , the many advantages of high early strength , can significantly improve the quality of cementing effectively prevent the leakage of cementing its damage to the oil and gas layer .
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