Oil casing is also called oil special pipe, mainly used for oil and gas well drilling and oil and gas transmission.

The utility model includes oil drilling pipe, oil casing and oil pumping pipe. 

Oil drill pipe is mainly used to connect the drill collar to the drill bit and transfer drilling power.

Oil casing is mainly used to support the well wall during drilling and after well completion, so as to ensure the drilling process and the normal operation of the whole well after well completion.

Suction tubing mainly carries oil and gas from the bottom of the well to the surface.

Oil casing is the lifeline of oil well operation. Due to different geological conditions, the underground stress state is complicated, tensile, compressive, bending and torsional stress act on the pipe body, which puts forward higher requirements on the quality of the casing itself. Once the casing itself is damaged for some reason, the entire well may be reduced or even scrapped.

According to the strength of the steel itself, the casing can be divided into different steel grades, namely J55, K55, N80, L80, C90, T95, P110, Q125, V150 and so on. Different well conditions, well depth, the use of steel grades are also different.

In the corrosive environment, the casing itself is also required to have corrosion resistance.

In the place of complex geological conditions, it is also required that the casing has the performance of anti-collapse.