Auger drilling technology with machine tools

Earthwork, despite its simplicity, is considered the most difficult process. Auger drilling is a way to facilitate and speed up wells while minimizing the risk of rock collapse. High-tech equipment allows production to be carried out almost all year round, regardless of weather conditions.

What is auger well drilling

In regions where soils with a low hardness index prevail, preparing the well for the installation of water intake equipment causes many problems. Therefore, when drilling sandy and sandy-gravel soils with a depth of up to 60 m, and sometimes even more, the auger method is used. The design of the equipment is represented by several elements.

• The auger is a device that is a metal pipe with a drill head-chisel and a screw-like fixed iron flange plate for removing destroyed soil to the surface. The product is prefabricated and consists of several elements that are interconnected during operation.
• The chisel is fixed at an angle of 300 to 600 to the bearing axis. The looser the soil, the lower the angle value should be set. When driving through hard gravel and pebble formations, it is recommended to use a head with high-strength technical diamonds. The borehole section usually does not exceed 600-800 mm, but in case of an exception, the use of screws of 1500 mm or more is allowed.
  

  

• During long-term work, the device heats up, as a result of which the rotational process is reduced. Therefore, more and more often, the auger for drilling wells has a feed channel through which water or air entering the cutter cools it. However, in general, the process of lowering the temperature occurs due to the contact of the head with the destroyed soil.
• The tool axis is made of medium carbon alloy steel with increased strength and weldability. High-manganese steel helical blades are welded to the pipe. The cutting edge is made of case-hardened high-alloy steel, which increases the hardness, avoiding the appearance of brittleness.
• If it is necessary to drill to a great depth, special mechanisms with a rotator are used, the speed of which depends on the diameter of the well: with a large one, it varies in the range of 100-250 rpm, and with a small one, it reaches 500 rpm.

  

• Auger drilling with LBU 50 machines is often used in conjunction with the casing method or plugging technology. Such structures make it possible, simultaneously with soil sampling, to strengthen the well, installing walls that hold the rock and thereby prevent collapse. In addition, mines made using these technologies do not require flushing.
• The drill head with auger can be either separate or solid. The combined option is called auger. The main requirements for the equipment are its reliability, mobility and portability.

The auger method is used mainly in the arrangement of wells with a low amount of fluid intake or for the formation of shallow wells. In the first case, mechanized labor is used, and in the second, manual labor can be used. In addition, this method is widespread in engineering and seismic surveys of hydrogeological surveys in the search for minerals.

Auger drilling principle

The method is based on a rotary action, which, depending on the forthcoming amount of work, is performed manually or mechanically.

1. When choosing equipment, it is taken into account that the flange is intended only for transportation, therefore the diameter of the bit or drill should be 20-40 mm larger than the auger section. With continuous drilling at high speed, centrifugal force presses part of the soil against the walls of the mine, compacting them, which contributes to the formation of a sludge crust.
2. The workflow should run with a minimum number of interrupts. For increased torque and productivity, the equipment is mounted on a chassis.
3. The technology of auger drilling of wells performed by machines of the LBU 50 type includes: cooling of the working tool, transportation to the surface of destroyed soil, strengthening the walls of the resulting mine. The use of mobile rigs reduces the loss of time when changing the location of the drilling rig. The use of this equipment allows you to deepen up to 200 meters with a section of 190 mm. The presence of the hammer allows the formation of a well with a diameter of 550 mm.
4. To start the auger, it is necessary to deliver it to the place and put it into working position by lowering the support shoes. After that, drilling takes place. The directional movement of the auger at high speeds is ensured by the rigid design of the installation. Additional sections are added as you dive.
5. When drilling a well with your own hands using a home-made drill and additional industrial equipment, the technological process does not change. The only difference is the dimensions of the mobile device, as well as the depth limit of 60-70 meters.

The auger drilling method allows you to make a pass in the vertical, horizontal and inclined planes. The technology involves the use of a hydraulic station. When performing work, the walls are simultaneously cased with metal pipes. The rest of the process is identical.

Advantages and disadvantages of the method

According to statistics, the cost of producing wells using auger drilling is the lowest, and the speed of putting them into operation is the fastest. However, this method has both pros and cons.

In addition to the speed of work execution, the positive aspects include the simplicity of the equipment and the uncomplicated technological process, which allows homeowners to perform small-volume work and get to deep-lying aquifers on their own. The tool is easy to assemble and allows for quick replacement of worn parts. There is no need for water to spill the shaft during drilling and there is no possibility of removing soil without removing the tool. A plus can be considered the absence of the need to engage in long-term pumping of the well when it is put into operation. Clay, sand and other impurities in the shaft are virtually absent, water pump filters are not clogged, reclamation is not needed.

The technology also has a lot of negative sides. The main ones are the restrictions on the depth and width of the well, as well as the inability to drill in any soil. Even if the soil parameters meet the technological requirements, the presence of a large stone on the path of the drill may lead to the need to change the site. In addition, during operation, there is a large load on the tool drive and may be disassembled or damaged. That is why the use of this method is most common in regions with close occurrence of potable waters and with weak soil. The disadvantages of screw wells also include a small inflow of water, which may not be enough to meet the needs of a large family.