Research And Application Of Large Displacement Well Cementing Technique On BiJiaLing

This paper analyzes the development of cementing technology for large displacement wells at home and abroad,and aiming at the large displacement well in Bijialing area,analyzed the difficulties of cementing technology on the block,and targeted to put forward the control measures.Aiming at the problem of casing down and center,the theory of limit eccentricity is introduced,aiming at the problem of the frictional resistance of casing string with centralizer,the paper the theoretical analysis is carried out and a computational model is proposed,the measured data were analyzed and compared by field application,the actual measured results and calculated results,the error is guaranteed at 7% up and down,this model is more real and closer to the construction than the model without considering the influence of the centralizer.Aiming at the problems of cementing slurry system,combined with the characteristic of Bijialing block sealed length,prone to leakage in the process of cementing wells,this paper proposes a system the double-solidification mud slurry system with low density cement slurry and conventional density cement slurry in cementing construction,developed the corresponding assorted admixture,priority is given to the Fluid Loss Additive DWJS-1,Dispersant DWF,Early strength agent DWZ-1,the toughening material DWZR-105 which can reduce the elastic modulus of cement was developed.As the block of the long sealing section of large displacement well,low density cement slurry must be used to reduce hydrostatic fluid column pressure,the development of suitable density range of Bijialing block is 1.30~1.50g/cm3,the temperature range of 45 ℃ ~ 70 ℃ low-density cement slurry,the mud slurry system can better solve the problem of well leakage in the process of large displacement well cementing wells.Guided by theory of tight packing theory and the mechanism of super hybrid composite,developed a conventional density toughened cement slurry system suitable for the large displacement well of the Bijialing block,the system of cement slurry performance is stable and the thickening time can be adjusted,cement slurry thickening time is short,the elastic modulus of cement stone is low,and the elastic modulus(GPa)of 7D is between 5.02-5.27.