Abstract:

Salt bed creep has been a big challenge for casing program design for deep and extra-deep wells. It is also the case in the Tarim basin, where there are very thick, gypsum-bearing salt beds in the Carboniferous formations of Lunnan and Halihatang areas and in the Tertiary formations of Yinmaili area. During drilling into these formations, sticking of tool was often the case. Shear deformation or breakdown of the casing induced by salt creeping would occur shortly after completion. Therefore, the conventional methods of casing program design cannot satisfy the needs in this basin. In the present work, a method is proposed and the companying software is developed of casing
program design for deep and extra-deep wells, with salt bed creeping taken into consideration. The method and software have been used in designing the casing program of seven wells and have been proven valid and effective.

Key words: atrium, casing program design, extra-deep well, salt creep