Rotary drilling: This type of drilling uses weight and rotation to drill a hole by grinding the rock with a tool. Mainly used in oil production. Cuttings are brought to the surface under the pressure of drilling fluid injected into the drill string. Drilling fluid also helps to strengthen the well bore so that it does not need to be treated during the operation.
Down-the-hole drilling (rotary percussion drilling or rotary hammer drilling): This type of drilling uses a drill rig, with a rotating cutter (drill) to drill the hole, and a pneumatic hammer to hammer the bottom of the hole. The excavated material rises to the surface under the pressure of the hammer using compressed air. This rig is powerful and has a high rate of penetration, especially in rock. For artesian wells (wells in which water naturally rises to the surface under the pressure of groundwater) or geothermal drilling, air injection at the end of the drill pipe pushes water up the borehole, allowing the operator to immediately gauge the flow of water encountered. This type of drilling is used in hard and fissure ground up to a depth of 4000 meters. When the drill bit is off-center, the hole can be drilled using a casing advance system (installation of the tube by gravity) that reinforces the hole as it progresses.
Top hammer Drilling: This type of drilling uses a rig that also operates on a percussion system, but the rig remains outside the well bore. They are mainly used for small diameter drilling, for example for mineral exploration or installing tie rods in rock. This drilling system is used for shallow drilling where significant deviations may occur from the ground structure drilled through. This rig can work in any orientation.
Auger Drilling: This is a type of rotary drilling that uses a worm (auger). This type of drilling is primarily used in loose clay or sand. The worm brings the excavated material directly to the surface. For deep hole drilling, the auger needs to be lifted periodically to empty it of the excavated material.
Core drilling: Core drilling is similar to rotary drilling, but it uses the top to extract a sample inside the tool, called a core.
Percussion drilling: refers to the use of tools and drill bits to break rock under the action of gravity. This type of drilling can only be used vertically. To prevent boreholes from collapsing, they need to be protected while drilling. Once the cuttings interfere with the hole, replace the bit with a flap valve nozzle and reassemble the cuttings. The flap valve guide tube is a tube with an inclined flap in the lower part. The inclined flap fills the tube with excavated material and transports it to the surface.
Pipe jacking drilling: mainly used for the installation of horizontal pipes. The pipe is progressively pushed by impact, and at the end of the drilling operation, the excavated material is removed by water injection or by using an auger (endless screw). This technique is especially used to avoid transmitting vibrations to surrounding buildings or to avoid trenching.
Post time: May-11-2023