Oil casing has a purpose:
Petroleum casing pipes are steel pipes used to support the walls of oil and gas wells to ensure the normal operation of the entire oil well after drilling and completion. Each well uses several layers of casing according to different drilling depths and geological conditions. Cement is used to cement the casing after the casing is down. It is different from the Tubing and drill Pipe and cannot be reused. It is a one-time consumable Material. Therefore, casing consumption accounts for more than 70% of all oil well pipes.
Oil casing classification:
surface casings, technical casings and oil casings according to their usage.
Special oil pipe purpose:
Special oil pipe is mainly used for the drilling of oil and gas wells and the transportation of oil and gas. It includes oil drill pipe, oil casing, and oil pumping pipe. Oil drill pipes are mainly used to connect drill collars and drill bits and transmit drilling power. Petroleum casing is mainly used to support the well wall during drilling and after completion to ensure the progress of the drilling process and the normal operation of the entire well after completion. The pumping pipe mainly transports the oil and gas at the bottom of the oil well to the ground.
Oil casing purpose:
Oil casing is the lifeline to maintain the operation of oil wells. Due to different geological conditions, the downhole stress state is complex, and the combined action of tensile, compressive, bending and torsion stresses 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, etc. Different well conditions and depths have different steel grades. In a corrosive environment, the casing itself is also required to have Corrosion resistance. In places with complex geological conditions, the casing is also required to have anti-collapse performance.
Different types of casing used in oil extraction:
Surface oil casing: protect the well from being contaminated by shallow water and gas layers, support wellhead equipment and maintain the Weight of other layers of the casing.
Technical oil casing: Separate the pressures at different levels so that the drilling fluid can circulate normally and protect the production casing. Install anti-burst devices, leak-proof devices and liners in the well.
