Horizontal screw drilling rigs are used in capital construction for laying oil and gas pipelines, pipelines and telecommunication networks. Trenchless laying of pipes and cables is the difference between this method and a number of others when there is no way to overcome natural and artificial obstacles in a classical way.
When technology is used
Horizontal drilling is most often used in hard-to-reach places - on lakes, swamps, rivers, under buildings, railways, roads and in ecological zones. There are several methods for trenchless laying of communications - puncture, sanitation, horizontal auger drilling. The use of drilling machines accelerates the time of work, reduces financial and labor costs. During the laying of communications by drilling, there is no need for a large number of equipment and workers, land dump and improvement of damaged sections of the city territory.
Advantages of the Brown Screw Method
The trench communication technology is considered obsolete for economic and production reasons. The first benefit of horizontal auger drilling is the amount of work and the amount of labor required. One crew of workers manages the drilling rig, and the volume of excavated land is much smaller. At the same time, the construction time, depending on the length of communications, is reduced by 2-20 times.
Economic costs of horizontal directed work are reduced by 30%. In this case, it is not necessary to interrupt traffic when laying pipes under roads or rivers, and the railway and asphalt road remains untouched.
During drilling, the environment does not suffer, and the process itself causes a minimum of inconvenience to people. The risk of accidents at the site is minimized through the use of guided drill heads.
The disadvantage of horizontal drilling technology is the inability to work on moving soils.
Process steps
Horizontal auger drilling begins with the excavation of two pits - the start and the end (working and receiving). In the working pit, a drilling machine and additional equipment are installed, in the end, all work performed is completed and a pipe or case is received for it.
At the first stage, controlled pilot drilling is carried out when the direction and length of the channel are specified. This is how “shooting” is carried out with a thin drill, during which the possibility of an emergency is excluded, especially in urban conditions with an extensive network of pipelines and underground cables.
At the second stage, the drilled small-sized well is expanded by the method of forcing the casing, fixed on the booms of the expanders, to the desired diameter. The excavation of the earth is carried out by a mechanism, parts of which are collected on the working shaft of a horizontal auger drilling machine. The screws are located in a metal pipe placed in the well, and are located immediately behind the drill head.
The third stage consists in the preparation of the working pipe and its forcing after the casing. After laying the pipes in the received channel, the drilling rig and other equipment are removed from the pit, the communication parts are interconnected.
Horizontal Drilling Equipment
The horizontal drilling machines of the RVA press-screw type have a simple design, not counting the individual nodes of the diesel generator type. The installation is a bed on which a diesel generator with a block of hydraulic power cylinders is located. A carriage is attached to the frame of the drilling machine, which serves as guides for a given casing or working pipe. Rods with a drill head for pilot drilling are attached to the shaft of the hydraulic unit. Behind the drill is a primary transmission sensor, the information from which is transmitted to the operator’s console. Thanks to the sensor, the depth, range and angle of attack of the drill head are constantly monitored.
Additional equipment consists of a set of rods and pipes with screws that are dialed onto the rod as the earth is removed from a horizontal well. Sometimes RVA machines are produced not in a stationary form, fastened to the prepared site with anchor bolts, but on a pneumatic stroke.
Work result
Horizontal auger drilling allows to achieve high accuracy of laying underground utilities. Depending on the type of soil, the diameter of the obtained channel is 100-1 720 mm with a length of up to 100 meters. Deviation during drilling does not exceed 30 mm for the maximum length of the well. Metal, polypropylene or concrete pipes are laid in the drilled channel, connected to the lash in the working pit. The resulting wells are used for laying gravity drainage due to the even channel, cables or pipes in the protective case.