Common drilling methods

Drilling is a systematic project, and it is a combined operation in which many professions and jobs use a variety of equipment, things and materials. At the same time, it is a wheel-receiving operation with closely connected multi-programs and interlocking multi-links. The whole process of construction is quite complicated. There are many kinds of drilling methods. Here are some common drilling methods introduced by the company. 1. Use the cutting or grinding effect when the drill bit rotates to break the rock. According to the power transmission method, rotary drill can be divided into rotary table drill and downhole power drill: rotary table drill is equipped with a rotary table at the wellhead of the drill floor, and there is a square hole in the center of the rotary table. The Kelly at the upper end of the drill string passes through the square hole, and the Kelly is connected with the drill string and the drill bit. When the rotary table is driven by power, the drill string and the drill bit are driven to rotate together to break rocks. Downhole power drilling is to use downhole power drilling tools to drive the drill bit to break rocks. When drilling, the drill string does not roll and has little wear, which is especially suitable for drilling directional wells. 2. The drill is also called impact drill. The wire rope is used to send the drill bit to the bottom of the well, and the beam mechanism is driven by power, so that one end of the beam moves up and down, and the wire rope and the drill bit are driven to have an up-and-down impact effect, so that the rock is broken. With slow drilling speed and low power, rotary drilling is gradually replaced. However, it has the advantages of simple equipment, low cost and no pollution to oil layers, and can be used in some shallow low-pressure oil and gas wells and lost circulation wells. 3, impact rotary drilling. Connect the rotary drilling tool to the drill bit, and use the circulating liquid or gas to propel the mandrel of the rotary drilling tool, so that the drill bit can break the rock by both impact and rotation at the same time, which is suitable for medium and hard strata. 4. Flexible rod drill. The flexible rod made of steel wire and rubber is used to replace the drill pipe, and the downhole power drilling tool is connected to complete the successive mechanization of tripping, which has great potential. 5, erosion drilling is to make the jet impact force exceed the critical pressure of rock breaking to directly break the rock. 6. Drilling method using rotary table to drive drill bit to drill holes. A rotary table is installed at the wellhead of the drill floor, and there is a square hole at the center of the rotary table. The Kelly at the upper end of the drill string passes through the square hole, and the Kelly is connected with the drill string and the drill bit. When the rotary table is driven, the drill string and the drill bit are driven to rotate together, which breaks the rock. The drill string in the borehole is lengthened and deepened from time to time, and the drill cuttings return to the ground with the circulating mud.