Auger drilling refers to one of the types of rotary drilling. The term "screw" itself comes from the word "Schnecke", which is translated from German as screw, curl, snail.
Features of the work
This type of drilling differs significantly from other types, in particular in that during this work, the destruction of the destroyed rock and its transportation through the well is carried out not by the flow of treatment agent, but due to the rotation of the column.
Auger drilling is very widespread, it is a universal method used for sinking wells of small depth in soft or loose rocks. This method is convenient for performing work in pebble rocks. It is also widespread in seismic exploration, development of blast holes, in engineering studies of hydrogeological orientation, geological surveys, and the search for minerals.
Drilling technology
Drilling augers in the process of loosening and crushing the rock, and then moving the resulting product to the wellhead on a special screw conveyor. The technology of work includes three main points. These are: the process of cooling the tool involved in the destruction of the rock, transportation to the surface of the destruction product and the strengthening of the walls of the resulting well with raised rocks.
Auger drilling is performed with a drilling tool. There are three types of technological tools. Drilling equipment is a column of conventional augers with a chisel, a shop auger with a crown, ordinary and hollow columns with a removable chisel and a removable core receiver.
Widely used for working with loose rocks, a two- or three-bladed chisel having flat or spiral blades. In cases where auger drilling is performed to work with rocks of medium hardness, higher wear resistance is required, therefore, a rounded profile bit saturated with hard alloys is used.
During the work, high-tech special installations are used. The drilling speed is huge, so the requirements for the installations are mobility and high transportability. Installations are made portable or self-propelled.
The main positive feature of auger drilling is the involuntary self-fixing of the borehole walls with the destroyed rock when it rises along the augers, as it is “rubbed” and creates the effect of a kind of plastering.
Note that this process is a high-tech, but at the same time quite
organizationally simple way of conducting underground workings, in which the risk of collapse during operation is minimized. Auger drilling can be carried out almost always, regardless of the time of year. The surface deformation is negligible, which is very important when working under railways and roads, buildings and utility structures.
A noticeable advantage of the work is a sufficiently high speed, simplicity and small damage to infrastructure and the environment.
Experts from all over the world note a constant interest in this method of drilling and predict good prospects for its development.