The preparing and running casing technology of super deep and slim hole in Well Mashen-1

Well Mashen-1 is the deepest in Asia. The finally drilling hole is ?165.1 mm, run in ?146.1 mm liner. There are several problems increase the difficulty in running casing, such as high temperature, high pressure, small clearance, low helical buckling load, etc. Preparing and running casing comprehensive technologies are researched and used to solve the above problems. In borehole preparation stage, wellbore quality control technology, dynamic formation pressure bearing capacity experiment, assembly design and safty wiper trip technology are used to create good hole conditions. The whole operation process is analyzed by the simulation of running casing technology, which reduces the risk of sticking and leakage. The successful application of the above technologies provides experience for other super-deep well