The most challenging drilling problems encountered in Tahe Oilfield occurred in the deep salt formations. Most holes lost are caused by stuck drilling strings, stuck casing, and collapsed casing because of the special salt formations. Particular research is conducted to solve these problems. At first, the occurrence arose in salt formations are identified in detail. Then the components of typical salt rocks are analyzed, and properties such as plasticity, solubility, stability, and stress sensibility measured, some new techniques evaluated, and integrated techniques developed. As a result of implementation of the integrated drilling techniques, deep salt formations drilling in Tahe Oilfield has been substantially improved.
The main researching results presented in this paper are attached to the discussion of the salt formation problems, laboratory measuring and testing of the salt rock and evaluated techniques, and field drilling application. Integrated techniques recommended are particularized, such as borehole structure, salt water based mud system, expanding drilling and drilling string assemblies optimized.