Research And Improvement Of The Technology Of Injecting Cement For Stratified Well

With economic development and population growth,people's demand for water resources continues to increase.In order to meet people's needs,China's hydrogeological drilling and well drilling technology are facing challenges.The multi-layer well has the characteristics of small area and low construction cost,and has become a common method in hydrogeological surveys.The current commonly used method of multi-layer well is using clay ball to seal and well completion.Due to the long hydration time of clay balls,the limited depth of seal,and the complex operation,it is prone to various types of drilling accidents.An efficient and complete technology is urgently needed to stratified wells completion.The Center of Hydrogeological and Environmental Geological Survey of China Geological Survey has independently developed the technology of injecting cement for stratified well.Compared with the traditional using clay ball to seal and well completion,the construction is more efficient and the seal position is more accurate and it can achieve seal in deep wells.But as a new type of original technology,there are still deficiencies that need to be studied.Firstly,the technology of injecting cement for stratified well is introduced in detail from design to construction,the possible problems are analyzed,and solutions are proposed.Make it a complete technical system,lay the foundation for the promotion of this technology in China's hydrogeological survey,hoping to advance the development process of China's hydrogeological survey.The technology of injecting cement for stratified well has been successfully applied in some wells.However,China's geological conditions are complex,in some wells,where the stratum of fine grained,fine gravel needs to be backfilled,or the waterproof stratum is thin,Whether such wells can be applied with the technology of injecting cement for stratified well has not been verified.The article firstly studied the technology of injecting cement for stratified well through simulation test,proved thefeasibility of injecting cement in fine gravel to seal,obtained the design of minimum seal section and injecting parameters,observed the position of cement and the disintegration of cement slurry,the research results provide a basis for the construction design.Finally,by analyzing the possible drilling accidents caused by the technology of injecting cement for stratified well,using check valves to inject cement is proposed.By analyzing the conditions that the check valve should have,we designed a simple structure and used a flexible special check valve.The flow parameters of the check valve were measured through experiments,which confirm the feasibility of the method.It effectively avoids the drilling accidents caused by the failure to accurately grasp the initial setting time of cement slurry,making layering into wells more efficient and safe,make the construction of stratified wells is more efficient and safe.