Research and Application of Composite Bonding Plugging Technology
In order to solve the problems of difficult plugging and low success rate of plugging in complex lost-circulation formation,a composite bonding plugging technology was developed.Bridge plugging materials and polymer gel SVG were directly added to drilling fluid to improve the retention capacity and plugging effect of plugging slurry.In this paper,the polymer gel SVG system with different temperature range was formed by selec-ting the polymer SVG dosage and retarder.The plugging experiment shows that the composite bonded leakage plugging slurry formed by adding polymer gel SVG and bridging materials GT-MF and NTBASE has excellent plugging effect,and the sealing pressure of 8~5 mm ladder seam plate and 5 mm parallel seam plate reaches 60 MPa without breakthrough.The plugging mechanism is that after the composite bonded plugging slurry reaches the lost-circulation formation temperature,the polymer gel accelerates swelling,and the slurry thickens,showing strong adhesion.It can not only bond the plugging material,promote the retention of bridge plugging particles and bridge building,but also strongly bond to the wall of the leakage channel,improve the retention effect,and make up for the shortcomings of bridge plugging technology and polymer gel technology.It has a broad application prospect in formation with severe loss.
severe lossbonding pluggingbridging materialpolymer gel