The drilling method plays a very crucial role in drilling engineering. Different drilling methods are suitable for various stratigraphic conditions and engineering needs. Choosing the appropriate drilling method can effectively improve the drilling efficiency and quality and provide essential basic guarantees for resource development and infrastructure engineering construction.
What is the drilling method?
The drilling method involves the use of tools such as drill bits and drill rods to create holes in hard surfaces like rocks. Various drilling methods exist, and some common ones include:
Impact drilling
This method adopts repeated impacts with an impact hammer to break the rock surface by impact while the broken rock is out of the hole through the circulating fluid. Impact drilling is suitable for drilling rigid rock formations.
Rotary drilling
This method utilizes the rotary motion of the drilling rig to rub, cut, and crush the drill bit on the surface of the rock, and at the same time, the crushed rock is out of the hole through the circulating fluid. Rotary drilling is suitable for drilling in various rock types.
Impact rotary drilling
This method combines impact and rotary movements, utilizing the impact force of the impact hammer and the cutting force of the rotary bit to break up the rock surface and discharge it out of the hole. Impact rotary drilling is suitable for drilling hard and abrasive rock formations.
Down-the-hole drilling
This method utilizes compressed air or liquid to drive the drill bit through the rotator for drilling, which has the advantages of high efficiency and speed, good drilling quality, and a wide range of applications. Down-the-hole drilling is available for drilling projects in various rock types and stratigraphic conditions.
Pipe-following drilling
This method utilizes the casing to protect the hole wall, and at the same time, the rock drilling tool is drilled into the hole together with the casing. Pipe-following drilling is suitable for drilling in soft strata, strata with soil and rocks, or other complex strata prone to collapse.
In addition to the above drilling methods, there are many other drilling methods. We can choose the appropriate drilling method according to different engineering needs and stratigraphic conditions.
Importance of drilling method selection
First of all, the choice of drilling method directly affects drilling efficiency. Different drilling methods are suitable for different rock types and stratigraphic conditions. Choosing an appropriate drilling method can significantly improve drilling efficiency. For example, for hard formations, using percussion rotary drilling can achieve higher drilling speed and drilling quality; for soft formations, using pipe-following drilling can protect the hole wall and improve drilling efficiency.
Secondly, the drilling method also affects the quality of the core and sample acquisition. Different drilling methods have different ways and degrees of rock fragmentation, which directly affect the core quality and sample acquisition and analysis results. For example, the rotary drilling method can obtain relatively complete cores and samples, while the impact drilling method may cause the cores and samples to be broken or disturbed.
Finally, the choice of drilling method also affects decisions on resource development and infrastructure construction. By drilling different strata and rock types, we can obtain underground geotechnical information, understand geological structures and characteristics, and provide a significant decision-making basis for resource development and infrastructure engineering construction. For example, in bridge construction, rotary drilling can be used to understand the geological conditions and foundation stability of the bridge site, providing important parameters for bridge design.
Therefore, a suitable drilling method is significant in geological exploration and engineering construction. It is necessary to select appropriate drilling methods according to different engineering needs and stratigraphic conditions, combined with the actual situation and technical requirements, to ensure drilling efficiency, core and sample acquisition quality, and the smooth progress of resource development and infrastructure engineering construction.
