Application of oil casing

　　Oil casing is a steel pipe used to carry oil and oil well wall, so as to ensure the normal operation of the whole oil well during drilling operation and after well completion. Several layers of casing shall be used for each well according to different drilling depth and geological state.

　　Special oil casing pipes are mainly used for oil and oil well drilling and oil and gas transportation. It mainly includes oil drilling pipe, oil casing and oil extraction pipe. Oil drill pipe is mainly used to connect drill collar and bit and transfer drilling power. Oil casing is mainly used to carry the wellbore during drilling operation and after well completion, so as to ensure the progress of drilling operation and the normal operation of the whole oil well after well completion. The oil extraction pipe is mainly used to transport the oil and gas at the bottom of the oil well to the surface.

　　Oil casing is the core point to maintain the operation of oil wells. Considering the different geological conditions, the downhole stress state is relatively complex, and the tensile, compressive, bending and torsional stresses act on the pipe body as a whole, which points out higher requirements for the quality of the casing itself. If the casing itself is damaged due to some conditions, it may reduce the production of the whole well or even scrap it.