Research on inner suspension and its application to GIF cementing

In order to tackle the problems that the logging tool is stuck in late logging and the pressure difference caused by the displacement of drilling fluid by balanced clean water,bullheading of certain amount of inner suspension is carried out without affecting well cementing operation procedures,which helps prevent precipitation of solid particles and avoid false cement plugging.This paper introduces the construction technology of suspension and selects the most suitable suspension agents and regulators on the basis of analysis and experiments.Through laboratory experiments,the hydration time of suspension is as high as 10 hours.What’s more,the viscosity of suspension is low when the temperature is between 10 ℃ and 70 ℃,the performance of suspension is stable when the pH is ranging from 2 to 11,solid particles will be precipitated from the suspension when the pH is lower than 2,and the viscosity of solution decreases when the pH is higher than 11.No precipitates will be separated from suspension in Ca2+,Mg2+,and sodium chloride salts.Field test shows that the inner suspension of GIF cementing has excellent suspension performance and can fulfill the technical requirements of cementing construction.In addition,it solves the problem that the logging tool is stuck in late logging caused by the replacement of cement slurry by drilling fluid and can be widely used in practice.