How much do you know about the performance of oil casing

First, what is the role of oil casing in oil drilling?
Surface casing: Installed at the top, it suspends and supports subsequent casing layers; it isolates shallow surface water layers from complex shallow subsurface layers, preventing freshwater contamination by drilling fluid.
Intermediate casing (technical casing): Isolates formations with different pressures or complex formations prone to collapse or leakage.
Production casing: Protects the production layer and provides a pathway for oil and gas to flow from the production layer to the surface.
Drilling liner: Reduces the load on the drilling rig during casing installation and the load on the casing head after cementing, while saving significant amounts of casing and cement, thus reducing cementing costs.

Second, what is the difference between oil casing and drill pipe?
The main differences between oil casing and drill pipe are: 1. Different uses; 2. Different materials.
Oil casing is a steel pipe used to support the wellbore of oil and gas wells, ensuring the smooth operation of the drilling process and the overall well after completion. Each well requires several layers of casing depending on the drilling depth and geological conditions. After the casing is run into the well, it is cemented. Unlike tubing and drill pipe, it cannot be reused and is a disposable material. Therefore, casing accounts for more than 70% of all well tubing consumption. Casing can be classified according to its use as: guide casing, surface casing, technical casing, and reservoir casing.
A drilling string is a connecting rod used to transmit power. The typical components of a drill string include: drill bit, drill collar, drill pipe, stabilizer, special connectors, and kelly. The basic functions of the drill string are: (1) running the drill bit; (2) applying drilling pressure; (3) transmitting power; (4) transporting drilling fluid; and (5) performing special operations such as cementing and handling downhole accidents. A series of oil drill pipes in API standard E75 to S135 steel grades, with outer diameters from 2 3/8″ to 6 5/8″, as well as double-shoulder joint drill pipes with high torsional resistance and BNK C95S drill pipes in special steel grades for sulfur-containing oil wells. Primarily suitable for deep wells, horizontal wells, and extended reach wells in oil and gas exploration and development.