Oil casing drilling is also called percussion drilling. The wire rope is used to send the drill bit to the bottom of the well. The beam mechanism is driven by the driving force to move one end of the beam up and down. The wire rope and the drill bit collide up and down to break the rock. The drilling speed of Dayton rigs is generally relatively slow, and the efficiency is very low, and cannot meet the requirements of increasing well depth and complex formation drilling, so it is gradually replaced by rotary drilling. However, its equipment is relatively simple, low in cost, and will not pollute the oil layer. It can be used in some shallow low pressure oil and gas wells and water loss wells. Downhole power drilling is the use of downhole power drilling tools to drive the drill bit to break the rock. The drill string does not rotate during the drilling process, with less wear and long service life. It is particularly suitable for drilling directional wells. Downhole electric drills are divided into turbo drills, electric drills and screw drills.
Petroleum casing pipe is used for oil well drilling. It 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 well after completion. Petroleum casing can be divided into two types: short-threaded casing and long-threaded casing. According to national regulations, household casings should be bundled with steel wires or steel bands, and the exposed parts and connecting threads of each casing should be screwed with a protective ring to protect the threads.
The cutting or grinding action produced when the drill bit rotates causes the rock to be crushed. Rotary drilling rigs are currently the more common drilling method. The drilling speed is much faster than the Dayton drill. It is easier to deal with the complex conditions of wellbore collapse and blowout. According to the power transmission method, rotary drills can be divided into two types: downhole power drills and rotary bench drills. The rotary table drill is equipped with a rotary table at the wellhead of the drill floor. There is a square hole in the center of the turntable. The kelly at the upper end of the drill string passes through the square hole. The bottom of the square drill rod is connected to the drill string and the drill bit. Rotate with the drill bit to break the rock.
Generally, oil casing is essential equipment for oil drilling. Its main equipment also includes drill collars, core pipes, drill pipes and small diameter drilling steel pipes. At present, domestic tubing and casing are made by hot rolling or cold drawing.