Cementing technology of Well Tashen-1

Well Tashen-1 is an ultra-deep scientific groping well.The risk of cementing caused by ultra-depth gets higher.In order to ensure cementing quality and finish the casing running perfectly,the interpolation method is applied to the course of cementing,by which the channeling problem of super-large casing can be solved.The contradiction between cement density,cementing quality and leak in the hole can be solved by using the technology of single stage double plugging.The cementing in the range of over-long hole is realized based on applying the cementing technology of hanging firstly and then tiebacking.The difficulty of leak formation in cementing is settled by applying anti-channeling plastic cement slurry system of ultra-low density.The cementing problems caused by such inherent features of ultra-deep well sections as ultra-high temperature and pressure are solved by using the anti-sloughing and anti-channeling cement slurry system resisting high temperature.The successful cementing of Well Tashen-1 in all spuding provides favorable conditions for subsequent and also provides a valuable case-history example for the testing operation of other ultra-deep wells.