There are two main differences between
oil casing and oil drill pipe: 1. Different uses; 2. Different materials.
Oil casing is a steel pipe used to support the wall of oil and gas wells to ensure the normal operation of the entire oil well after drilling and completion. Several layers of casing are used for each well according to different drilling depths and geological conditions. Cement cementing should be used after the casing is run down the well. It is different from tubing and drill pipes and cannot be reused. It is a one-time consumable material. Therefore, the consumption of casing accounts for more than 70% of all oil well pipes. The casing can be divided into conduit, surface casing, technical casing, and
oil casing according to usage.
A rod is connected to a drilling tool to transmit power. The usual components of the drill string are drill bit, drill collar, drill pipe, stabilizer, special joint, and kelly. The basic functions of the drill string are: (1) tripping the drill bit; (2) applying weight on a bit; (3) transmitting power; (4) transporting drilling fluid; (5) performing special operations: squeezing cement, deal with downhole accidents, etc.
API standard E75 to S135 steel grades, series of oil drill pipes with outer diameters from 2 3/8" to 6 5/8" and double shoulder joint drill pipes with high torsion resistance and special steel for sour oil wells Grade BNK C95S drill pipe. It is mainly suitable for the construction of deep wells, horizontal wells, and extended reach wells in the process of oil and gas exploration and development.